Auto-Cut Systems Troubleshooting Power Supply Error

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Troubleshooting Ultracut & Autocut Systems from Status Codes
The power supply for these systems is made by another company to TDCs
specifications. The rest of the system, the Communications & Control Module (CCM),
Remote Arc Starter (RAS), and various gas controls (GCM 1000, GCM 2000, GCM
2010) were designed and are manufactured by TDC.
Because the CCM, which is the “brains” of the system, is mounted into the rear panel
of the power supply one might consider it to be part of the power supply however, for this
discussion, is it considered a separate part. References to “power supply” or “power
supply boards” do not include the CCM.
On start-up and during operation, the power supply control circuitry, along with the
CCM, performs various tests. If the circuitry detects a condition requiring operator
attention, the CCM causes the Status Indicator on the front panel to flash a 2-part code.
First part of the code indicates a code, the second part a particular condition within that
group. After 4 seconds the sequence repeats.
Example: Indicator flashes 4 times; the condition is in group 4. After 1.2 seconds
delay, the indicator blinks 3 times; the condition code is 4-3, indicating the coolant is
overheating or has overheated. After a 4 second delay, the indicator repeats the sequence
until the condition is corrected.
The code groups are:
Group 1
Process Codes
Group 2
Power Supply Codes
Group 3
Gas Control Codes
Group 4
Coolant System Codes
Group 5
CANBus Code
Group 6
CCM Fault Codes
Some conditions can be active indefinitely, while others are momentary. Some
momentary conditions can shut down the system then they are gone. The power supply
and the CCM latch and hold the codes that are set by momentary faults so you can see
why the code was set. Most latched codes are cleared by reapplying CNC Start. A few
require shutting the power supply off to reset it.
The status indicator may show multiple conditions in sequence; it is important to
recognize all possible conditions that may be displayed.
Troubleshooting (General)
A number of the measurements will require probing of some small connectors or
measuring signal on ribbon cables. For probing the small connectors, standard meter
probes are usually too big. I suggest making a couple probes. Use steel wire copper
buss wire that is small enough isn’t stiff enough, it just folds over. One idea is take a
socket from an Amp mat-n-loc or similar connector into which your meter probe will fit
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and crimp a small piece of steel wire, 0.020 to 0.025” dia. (0.5-0.6 mm) works best, into
where wire would normally be crimped. A paper clip is a little too big.
Insulate all but the end of wire and slide these onto your meter probe.
If your meter has alligator clip adaptors you could hold the wire in these as well, be
sure they don’t short together.
Ribbon cable: There are 3 ribbon cables, 16 ckt., 26 ckt. and 34 ckt. For earlier units to
measure ribbon cable signals requires test adaptors. For later units we smartened up and
included an extra receptacle on the ribbon cable for taking measurements. For the16 ckt.
ribbon the extra receptacle is just above the top inverter, for the other two it is next to the
ends that connect to the CCM. The home made probes above work will for this.
For earlier units test adapters can be used or buy new style ribbon cables.
I have used these adaptors which are available from Digi-key.
Digi-Key Part Number 922576-26-ND Price Break Unit Price Price
1
15.45000 15.45
Manufacturer Part Number 922576-26-I
Digi-Key Part Number 922576-34-ND Price Break Unit Price Price
1
17.24000 17.24
Manufacturer Part Number 922576-34-I
They do not have one for 16 ckt. But the 20 ckt one can be cut down. Or you can buy a
40 ckt and make two 16’s out of it making each 16 ckt adaptor a little cheaper.
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Digi-Key Part Number 922576-20-ND Price Break Unit Price Price
1
14.84000 14.84
Manufacturer Part Number 922576-20-I
Digi-Key Part Number 922576-40-ND Price Break Unit Price Price
1
18.90000 18.90
Manufacturer Part Number 922576-40-I
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Power Supply Status Codes
Group 1, Process Codes
1-1
E-Stop Activated or Plasma Enable Off
Code 1-1 is activated by either an open circuit between TB1-1&2 (External EStop) on CCM I/O PCB or Plasma Enable switched off. 1-1 is not a latched code,
it clears as soon as condition is fixed. Plasma Enable switches are on GCM 2010
and GCM2000 gas controls and the Remote HMI.
Causes for 1-1 code (see detailed descriptions below):
 GCM 2010 or GCM 2000 J5 on PCB plugged in wrong.
 Missing one phase of AC Input. Check for 3 phase power at input
terminals. Blown fuse, open connection.
 If D21, CNC_E-STOP LED, on CCM I/O board is not illuminated then
External E-Stop circuit is not satisfied. Either jumper TB1-1 & 2 (CCM
I/O board) is missing or user installed external E-Stop has a fault.
 If D21 is illuminated and D2, E-Stop_PS, is not on then Plasma Enable
switch on gas control (GCM 2000, GCM2010) or HMI not on or fault in
Plasma enable circuit. See quick test in section on Plasma Enable below.
 If both D21 and D2 are illuminated the CCM is defective.
GCM J5 plugged in wrong interrupts the Plasma Enable circuit. Some gas
controls have J5 header which is un-polarized allowing J5 to be reversed. Others
have 17 pin header but 16 circuit receptacle. These should be installed so circuits
1-16 are connected leaving pin 17 exposed. If instead, pin 1 is exposed Plasma
Enable is interrupted.
Missing phase.
Power to the control circuits comes from two of the 3 input phases. If either of
those two are missing there will be enough voltage to the CCM to power its CPU
but not the I/O board circuits including the E-Stop. Thus it will falsely detect EStop. This condition can be confirmed by measuring the voltage at TP2 to TP1 on
the CCM’s I/O PCB (larger of the two boards). Voltage here is normally between
29 to 41 VDC. If a phase is missing it will about half the normal voltage.
If the 3rd phase is missing CCM will receive correct voltage but will correctly
signal missing phase. Check L1 input busbar. (code 2-1). If missing phase is due
to blown fuse check for shorted SCR in inverter(s). See code 2-1 for instructions.
External E-Stop
E-Stop input is on CCM module TB1-1&2. This circuit must be closed for
normal operation; open activates E-Stop, generating 1-1 code. CCM is supplied
from the factory with a jumper across TB1-1&2. The jumper may be replaced
with an external switch for remote E-Stop. D21 (CNC E-Stop) on the CCM I/O
PCB will light when TB1-1&2 is closed.
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If D21 is not on, problem is missing jumper, defective external E-Stop switch
or its wiring or the CCM is defective. Note, the CCM is replaced as a unit;
individual boards are not replaced separately.
If D21 is on, then Plasma Enable circuit is causing the 1-1 code. K5, E-STOP
relay, when off, disables the power supplies power circuits and coolant pump.
Also disables the Gas Control preventing gas flow.
Plasma Enable Circuits.
When External E-Stop is satisfied, D21 LED on, relay K3, E-Stop CNC, is
closed applying +15VDC to K5’s coil.
HMI is an optional touch screen control panel. When not present, relay K6 on
the CCM I/O PCB is not energized connecting J7-1 to gnd. Gas Control’s Plasma
Enable Switch, when on (closed), applies gnd, through a relay in the Gas Control,
to K5’s coil. D2, E-Stop PS, will illuminate when both external E-Stop and
Plasma Enable are satisfied, K5 energized. K5’s contacts, when closed, enable
both the gas control and the power supply’s power circuits.
Quick Test
If D2 in the CCM is not illuminated to determine if problem is in CCM or
GCM 2000 or 2010 Gas Control (or cables & harness) first disconnect the HMI
cable, if present, then jumper J7-1 to J7-2 ( on CCM I/O PCB, the larger board).
If D2 comes on problem is in the Gas Control or the control cable. Otherwise it is
the CCM.
In the Gas Control if D25 (Plasma Enable LED on the main PCB) is
illuminated, jumper J5-6 to J5-7 (connector on main PCB). If D2 on the CCM
I/O PCB comes on now the GCM main board is defective. Otherwise problem is
In the GCM harness or the control cable.
If D25 (Plasma Enable LED) on the main PCB is not on, jumper J5-1 to J5-1
(connector on main PCB). If D25 still not on main PCB is defective. Otherwise
the Plasma Enable switch or its wiring to J5 is bad.
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J9 connects 1:1 to J54
HMI Power connector
on rear panel of CCM
J9
24 VAC
24 VAC
24 VAC RET
4
150
1N4004
1
24 VAC
Power
to HMI
1
2
3
4
5
6
Jumper in
HMI
PLASMA ENABLE
2
3
K6
100uF
63V
8
5
7
6
+15V
K3 E_STOP CNC
K5-E-STOP
2
6
+
5
1.2K
1N4004
E-STOP
to GAS
Control
4
3
1
DPST
D2
E-STOP
to Power
Supply
E-STOP_ PS
GREEN
To CPU
E-Stop
Input
10
75.0
9
47K
1N4148
CD4050BC
0.1uF
J7
1
2
3
4
5
6
7
8
9
PLASMA ENABLE
To
To
J55 (GCM) pin 1
J55 (GCM) pin 2
Jumper J71-2 to simulate GCM plasma enable signal.
1-2
Pilot Ignition Failure
Pilot ignition requires both HF from the arcstarter (either the Remote Arcstarter
(RAS) or GCM 1000), the pilot contactor on and for units with chopper pilot
regulator, enabling the pilot regulator circuit.
Causes for 1-2 code:
 No HF
 Pilot Contactor not closed
 Pilot Regulator (chopper) has no power.
 Pilot Regulator (chopper) not enabled
 No pilot demand to chopper
 Pilot Regulator (chopper) defective
No spark at RAS spark gap
Pilot ignition phase starts at end of pre-flow or immediately after applying Start
if system is still in post-flow. If pilot doesn’t ignite within 15 seconds of entering
ignition phase, system faults and sets code 1-2.
1. Check that spark gap is set for 0.062” +/- 0.002”. If gap is too high there may
not be enough voltage from T1 to fire the gap.
2. 120VAC from J59-7 & 9 on the power supply connects to J58- 7 & 9 on the
RAS or GCM 1000. From J58 it goes directly to the line filter and passes
through the filter to primary of T1. During the ignition phase, for 15 seconds
following Preflow, check for 120 VAC on the T1 side of the line filter.
 If 120 VAC not present go to step 3.
 If 120 VAC is present and still no spark, T1 may be bad. Remove power
and measure resistance of T1 primary and secondary. T1’s primary should
measure about 3-7 ohms. It’s secondary about 25-35 K ohms. If either
measurement not correct replace T1.
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
If T1 measures OK, check for shorted capacitors C1-C3.
3.
No 120 VAC to T1 primary during the ignition phase (15 seconds following
Preflow) check for 120 VAC into the line filter. It it’s there replace the filter.
If not present go to step 4.
4.
CCM sends signal HF Enable (active low) at J35-10 to CN10-10 (other end
of ribbon cable) on power supply board WK-5602 (PCB5). Signal leaves
PCB5, still active low, on CN8-4 and goes to CN8-4 of relay board WK-5628
(PCB7) closing relay RY5. 120 VAC from T1 passes through rear panel
circuit breaker CP2 to PCB7’s CN6-1 & 4. RY5 contacts closed sends this
120VAC out on CN7-1 & 4 to rear panel RAS connector J59-7 & 9 to turn on
the Arcstarter (RAS or GCM1000).
Ultracut / Autocut
RAS 1000
J59-RAS J58-RAS
1
1
2
2
3
T1
460
C.P2
120.
220
0___
CN6
AC120V @ 1A
RY5
CN7
1
1
2
2
3
3
4
4
Part of PCB7
WK-5628
Relay PCB
0___
AC120-RAS
0V RAS
KEY PLUG
3
4
4
5
5
6
6
7
7
Line1
8
8
GND
9
10
11
12
13
14
9
10
11
12
13
14
15
16
Line2
T1 Assembly
R1 6.8K 1W
T1
3
Load1
1
2
Load2
R2 6.8K 1W
4
Line Filter 1ph
TX1P8S
Pilot Regulator (chopper) Power
Chopper module bias power is high DC voltage supplied to CN5 on the larger
of the two chopper PCBs. For all power supplies except 600V, bias power for
the chopper comes from P1 (white wire) and N2 (black wire) from top inverter
module PCB9 (WK-5605). Voltage will be around 600-700VDC for 400 & 460V
inputs and 300-350VDC for 208-230 volt input.
For 600V power supplies the chopper bias comes from a diode D3 mounted to
the rear of the T1 transformer. Power to D3 comes from the T1’s 200 VAC
primary.
Pilot Enable & Pilot Demand
As soon as CNC Start is applied, CCM makes signal Pilot Enable true (active
low) on J35-9. /Pilot Enable goes to PCB5 (WK-5602A) CN10-9 where it turns
on relay RY1. 110 VAC from T1 goes to CN9-1. RY1 connects the 110 VAC to
CN9-5 to turn on the pilot contactor.
For Chopper Pilot units /Pilot Enable from PCB5 is sent to the Chopper module
on CN33-2 (CN33-4 common) to CN2-2 to turn on the chopper. Signal is high,
about +15 VDC when not enabled and goes low, nearly zero volts to enable the
chopper.
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For resistor pilot units where the pilot current is controlled by the main inverter,
Pilot Enable causes PCB5 to connect Pilot Demand to the inverter signal I_REF.
See section on Eagle 100-300 Demand Signals – Cutting & Pilot for
troubleshooting.
For Chopper Pilot units Pilot Demand is sent from CN33-3 (CN33-4 common)
to CN2-3 chopper. See section on Eagle 100-300 Demand Signals – Cutting &
Pilot for troubleshooting.
Pilot Regulator Defective
If chopper has bias power, Pilot Demand and is enabled but still no pilot it may
be defective. It can either just not be working or can be shorted.
A quick test is to bypass the chopper. Connect a jumper wire capable of 30A
between the pilot busbar (where the pilot lead connects to the power supply) and
the anode of D2. Set the output current to 30A to keep the pilot current low.
Pilot
Contactor
Jumper
Chopper
T1
D2
Anode
Pilot
Busbar
Pilot only, DO NOT TRANSFER. If the torch pilots the problem is in the
chopper.
More detailed chopper tests.
To test chopper disconnect the cable to the arcstarter at J59 of the power
supply rear panel. Connect voltmeter between busbars under the cover on the rear
panel where the Torch (negative) and Pilot (positive) leads connect. Attempt to
start the unit. If voltage is equal to OCV (open circuit voltage), around 300400VDC, chopper is either working or shorted. If voltage is about ½ the OCV
chopper is not working.
Test for shorted chopper.
 First turn off input power and jumper across diode D2 (mounted on the
chassis to the rear of the chopper). Leave jumper on for a couple minutes
to insure chopper capacitors bleed down to zero volts.
 Chopper freewheel diodes. Measure resistance between TB2 and TB4 on
chopper. Expect to see over 20K ohms with it slowly increasing as it
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
1-3
charges a capacitor. If using a meter with a diode scale, expect to see
continuity one way (diode forward biased) and open with probes reversed.
A low resistance with either method indicates a short.
Chopper IGBTs. Measure resistance TB1 to TB4 on chopper. Should be
open circuit. . If using a meter with a diode scale expect to see continuity
one way (diode forward biased) and open with probes reversed. A low
resistance with either method indicates a short.
Pilot Out
Pilot has ignited as sensed by Pilot On signal, but went out on its own before the
timeout (85 ms. or 3 sec.).
Possible causes:
 Preflow pressure too high, check cut charts for proper setting.




Cutting current set too low for the torch parts being used. Pilot current
level is automatically set based on the cutting current. A low cutting
current results in a lower pilot current that may not be able to sustain a
pilot for higher current torch parts.
Remote Analog Current Control switches set wrong can also result in
lower than normal pilot current setting. See section on these switch
settings under next section for code 1-4.
Pilot Regulator (Chopper) Defective, refer to previous section 1-2 for
quick test to see if chopper is defective.
Defective Inverter module. The inverter modules supply the power for the
pilot while the pilot regulator (chopper) regulates its current. For power
supplies with 2 or 3 inverters (150A, 200A or 300A), each inverter
supplies a portion of that power. If one inverter is not working it may be
enough to start a pilot but not to maintain it thus code 1-3, pilot out early.
o To determine if one inverter is not working, first disconnect the
arcstarter cable so the pilot won’t try to start and there will be no
HF.
o Disconnect the 16 circuit ribbon cable from all but one of the
inverters (CN6 on inverter PCB13). Prepare to measure DCV
approximately 300-400VDC between the torch (-) busbar
connection and the Work (+) busbar.
o Apply CNC Start, voltage should immediately be present and stay
on for about 15 seconds. After 15 seconds you will get a 1-2 code
but that is normal because with no HF the pilot can’t ignite. If
voltage is present repeat the test with each of the other inverters.
Any inverter that the voltage doesn’t appear is defective.
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1-4
Loss of Transfer
Arc transferred to metal for at least 50 ms. then went out.
Causes for 1-4 code:
 Cut demand set much lower than recommended for torch parts, i.e. 100A
consumables in torch but cut current set for 30 or 50A (or zero). Current may
be too low to keep arc on.

Torch standoff too high for cutting process being used.

Preflow gas flow to low due to a leak somewhere between the preflow
regulator and the torch? Check for leaks.

Remote analog current control switches set wrong.
If remote analog current control is being used (SW8-2 (CCM CPU PCB)
is on and SW11 (CCM I/O PCB) is set to “A” (down) position) but no analog
voltage connected to TB1-10, then cut demand will be zero, pilot will be
weak, depending on torch height it may still transfer but will immediately go
out.
If remote analog current control is not being used but either SW11 is set to
“A” or SW8-2 is on also results in zero cut demand.
If system is Autocut with GCM 1000, current control is analog voltage
from the GCM 1000 front panel pot.
SW8-2 should be off and SW11 set to “B” (up) position. With pot at max,
check for 3.3V on CCM I/O PCB TP9 (TP1 common). While turning pot
toward min TP9 voltage should vary linearly to zero V.
POWER SUPPLY
CCM
J7
TP9
+10VDC
0-3.3V
SW11 3
1
2
Divide
by 3
1
2
3
4
5
6
7
8
SPDT
TP1
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J55
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
GCM 1000
J59
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
(8)
(9)
(10)
(8)
1
(9)
2
(10)
3
CURRENT CONTROL POT
10
1-5
Off the Plate (software not currently implemented)
Off the Plate feature, when activated (CCM CPU board’s SW5-2 on), detects
rapid rise in voltage when torch runs out of metal and cuts the arc off to prevent
bending and stretching the arc too far which can damage the torch parts. Status
code 1-5 is not a fault but instead indicates Off the Plate has functioned.
1-6
Transfer Timeout
Pilot time is limited to either 85 ms. CCM SW8-1 off (default for pierce
starting) or 3 seconds SW8-1 on (used for cutting over holes, expanded metal,
etc.). Arc must transfer before pilot time ends. Code 1-6 set if no arc transfer
(current in work lead) was sensed before pilot timed out.
Causes for 1-6 code:
 Torch too far from work,
 Cut current set too low for torch parts being used. Pilot current is set based
on cut current. If cut current is too low pilot current will be lower and
may not transfer at the height used for higher current consumables.
 Preflow pressure/flow too low.
 Remote Analog Current Control switches set wrong can also result in
lower than normal pilot current setting. See section on these switch
settings under section for code 1-4.
 Work lead not connected.
1-7
Tip Saver
Tip saver circuit is not currently implemented.
1-8
Possible Shorted Torch
CCM measures both electrode and tip voltage. If, while cutting, tip voltage rises
to within 30V of the electrode voltage CCM shuts off cut and sets 1-8 code.
Causes for 1-8 code:
 Gas Flow/pressure too low for consumable parts being used.
o If gas source pressure is not well regulated it is possible pressure
may be OK at times and drop too low at other times such as during
a cut.
 Cut current set too high for consumable parts being used.
 Physically shorted torch body between anode (tip) and cathode (electrode).
It is more likely a shorted torch body, depending on the resistance of the
short, will set code 2-7 (Unwanted Current) as that is measured prior to
starting cut while shorted torch is measured while cutting.
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Group 2 codes, Power Supply Codes
2-1
Missing Phase.
System required 3 phase power will not operate on single phase. If phase L2 or L3
missing causes code 1-1 (see code 1-1 explanation). Phase L1 missing sets 2-1
code.
Causes for 2-1 code:
 Blown fuse in wall fuse/disconnect box or phase missing from power
distribution.
 Loose connection on power cord.
 C.P1 (On/Off SW) defective.
 Shorted inrush SCR in inverter module input rectifier bridge.
 Defective power supply PCB (PCB1, PCB4, PCB5)
 Defective CCM
Missing Phase
The power supply checks for 3 phase voltage at both the power supply input
terminals and at D1 (3 phase bridge on horizontal panel behind front panel)
coming through C.P1 (front panel On/Off SW). Measure the 3 phases at the input
terminals L1-L2; L2-L3; L1-L3. Do not measure from Phase to neutral. On D1
measure the 3 phases on the red, white & black wires coming from the bottom of
C.P1. If present at the input terminals but missing at D1 it is likely that C.P1 is
bad.
Shorted SCR
When power is first applied the input contactor for one inverter closes
momentarily then opens. This keeps repeating a number of times during which
code 2-1 will flash. After a while contactor may stay on and you could cut
however allowing this to continue can damage the contactor and possibly the
rectifier bridge and input capacitors.
When power is first applied the AC input voltage is rectified to DC and allowed
to slowly charge the input capacitors through a pair of resistors. Then when the
capacitors are fully charged an SCR (part of the input bridge) is turned on
connecting the DC directly to the capacitors. With the SCR shorted very high
currents, limited only by the line impedance, flow through the rectifier bridge and
into the filter capacitors. If you have a missing phase the line voltage drops every
time that phase should be supplying voltage. The missing phase detection circuit
detects the drop. The high currents caused by no inrush limiting cause the voltage
to drop momentarily each time the contactor closes. The missing phase detection
circuit interprets this drop as missing phase thus the 2-1 code.
To determine if SCR is shorted, find the inverter module(s) on the left side of
the unit. The input bridge is to the left end of the module (rear of unit).
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R2
+
measure resistance between terminals marked R2 and +. Should measure be
hundreds or thousands of ohms. A short will read less than 100 ohms.
Power supply boards
Look on PCB5, WK-5602A, for LED2, Missing Phase, illuminated brightly.
When phase is not missing will still be on but not so bright. (Don’t blame me, I
didn’t design it.) If not, problem is likely in the CCM but still could be in the
output side of PCB5.
PCB4, WK-5604, has signal VACIN derived from rectifying 3 phase input on
PCB1 (Refer to simplified schematic in section 2-2). VACIN is normally a 3
phase full wave rectified DC level with little ripple. Looks like this:
Voltage that becomes VACIN comes from PCB1 and
goes to CN2-1 on PCB3 where it is passed directly to PCB4 which is daughter
board that plugs into PCB3.
VACIN can be measured on PCB3 (WK-5694) between CN2-1 (+) and PGND
at CN2-2 (-). PGND may also be found at CN1-1 which may be easier to use than
CN2-2.
Note, CN2 must be connected while taking this measurement.
VACIN should be between 7.7 to 9.5V for 460 VAC or 4.3 to 4.7 V for 208-230
VAC Power. For units with 400V input voltage (CE & CCC units) VACIN
ranges from 6.25 to 8.25V. 600V? If a phase is missing it will be somewhat
lower.
When a phase is missing VACIN looks like this:
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When a phase is not missing the optoisolator, PHC2, output transistor is off or
open so voltage across CN7-1 & 2 is +15 VDC. When a phase is missing, the
opto turns on for the time that VACIN is lower than 2.5 V making the output
across CN7-1 & 2 into a string of low going pulses.
PCB4
PCB5
+12VDC
+15V
1
PHC2
CN7
4
VACIN
3
2
+
1
2
3
4
5
CN7
1
2
3
4
5
Pulse
Detector
When L1 phase is missing, the voltage measured across CN7-1 & 2 will be less
than 15V, probably around 12 V.
Determining which PCB:
Disconnect CN7 from either PCB5 or PCB4. If 2-1 code still present after
restoring power then problem is in PCB5 or the CCM. If code went away then
look at PCB1 or PCB4. Also remember bad connections in harness connectors
can cause faults too.
PCB1
If 3 phase power of proper voltage is connected to the power supply and VACIN
is low or zero PCB1 or connections to it may be defective.
PCB4
If the voltage at CN7-1 & 2 is zero may indicate VACIN is not getting to PCB4
or PCB 4 is defective. Also possible there is a bad connection between PCB4 &
PCB5.
PCB5
If voltage across CN7-1 & 2 on PCB5 (same as CN7 on PCB4 unless bad
connection) +15V but LED2 on PCB 5 is illuminated then PCB5 is defective.
If LED2 is not illuminated, PCB5 should apply a low signal over the 34 ckt
ribbon cable from CN11-12 on PCB5 (common is TP0) to J36-12 (common TP1
on CCM I/O PCB) telling the CCM all 3 phases are present. If J36-12 is not low
then PCB5 is defective or the ribbon cable is open.
CCM
If J36-12 is low but code 2-1 is still flashing then CCM is defective.
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2-2
Input voltage out of range.
The Power supply contains circuits that monitor the AC input voltage. This
works as wrong voltage detection i.e. if unit is configured for 208-230 and 460V
is applied. If there is more than one inverter and one is configured wrong or the
harness connecting to CN1 (230V) or CN2 (460V) on the voltage selection PCB
in not connected it will signal wrong voltage, voltage out of range.
2-2 code will be set if input voltage goes outside the range 141-258 for 208-230
units; 304-533 for 400V and 460V units; 380-665 for 600V units. These ranges
are for wrong voltage detection. It does not mean the unit should be operated
anywhere within the range. For example, do not attempt to operate a unit
configured for 208-230 on 150 VAC.
Causes for 2-2 code:
 CN1 or CN2 connector on one or more inverter voltage select PCBs not
plugged in.
 Power supply inverter(s) configured for incorrect voltage.
 Input voltage is outside the range, too low or too high, or momentarily
goes outside the range. Poor power quality with drop outs or surges can
set 2-2 code. Because they are transient in nature are difficult to detect
w/o a power line monitor.
 At arc transfer as current ramps up Input voltage droops due to not
enough capacity or wires too small.
 Defective power supply PCB (PCB1, PCB4, PCB5) or CCM.
Symptoms when voltage is actually out of range:
If Start signal is not on:
 Code 2-2 blinks, input contactor MC1 (also MC3, MC4 in 2 or 3 inverter
units) and inverter fans shut off (after slight delay) when outside the range.
Coolant pump and fan(s) continues to operate unless voltage is so low it
cannot.
 If voltage returns to within the range input contactor(s) and inverter fans come
on and 2-2 code is automatically cleared.
If Start signal is on:
 Code 2-2 blinks, input contactor(s) and inverter fans shut off (after slight
delay) when outside the range. Coolant pump and fan(s) continues to operate
unless voltage is so low it cannot.
 If voltage recovers but Start remains on, input contactor(s) and inverter fans
come back on but 2-2 code continues to blink. Remove Start and 2-2 code
continues to blink. Reapply Start clears the code and unit operates normally.
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If code set just after arc transfer:
 Unit pilots OK and can perhaps cut at lower currents but higher current will
set 2-2 shortly after transfer. Wires to power supply or wires from fuse box to
mains too small for the current cause voltage drop as current rises. Voltage
will measure OK when not trying to cut.
Poor Power Quality:
 Voltage can go out of range momentarily from a few ms. to a couple seconds
then recover. Inverter fans are powered from a DC supply. Because of the
charge in the DC supplies capacitors the fans will run for up to a few seconds
after power is removed. If input voltage goes out of the range for a very short
time then recovers it may appear that the fans didn’t shut off at all.
AC Power Issues
For voltage drooping under load check the wiring to the power supply, both
the fuse box to supply and even more important because they are usually longer,
the wires coming to the fuse box from the main input are rated for the current
draw. Verify that no other equipment that also draws current is on the same
circuit. Verify that the factory’s main transformer can handle the increased load,
especially if they didn’t have a plasma there before.
Momentary voltage dropouts or surges are very hard to find. Often requires
testing with a recording line monitor that remains in place for a few hours or
days. All measurements below will appear OK because they are only off at the
time of disturbance. This can lead one to think the CCM is giving false codes
when in fact the system is responding correctly to voltage that is out of range if
only momentarily.
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Power Supply PCBs
Simplified circuit:
INVERTER MODULE
MC1
VOLTAGE SELECT PCB
JUMPERED
FOR 230
D1 & 2
PCB1
D3 & 4
R1-10
CN2
1
CN2
1
CN4
Voltage Level
Detection
Circuits
VACIN
PCB4
MISSING INPUT OUT
PHASE
OF RANGE
CN7
5
4
3
Input_NG
5
PCB5
1
Part of D1 Bridge rectif ier
4
CN1
CP1
3
6
MISSING_PHASE
6
RY 3
CN7
PGND
2
3
5
2
3
1
2
2
R1
R11
1
D5 & 6
PCB3
1
2
3
4
CN1 (CN2)
JUMPERED FOR
400-600
1
2
3
4
3 Phase AC
+15V
LED3
LED2
INPUT
NG
MISSING
PHASE
1
PCB7
MC1
RY 1 RY 1
RY 1
TP0
RY2
RY 2
8
+15V
CCM
460
T1
K5 E-Stop
220
0
BIAS TRANSFORMER PRIMARY
PCB5
LED3 on PCB5, WK-5602A, is normally illuminated in any case. For a
couple seconds after power is applied it will be bright while system is performing
tests. After that if it remains very bright, problem is likely either that voltage is
actually out of range (or inverter configured wrong), PCB1 defective, PCB4
defective. If the LED3 is less bright, problem is likely in the CCM but still could
be in the output side of PCB5.
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The input to PCB5 for wrong voltage signal, INPUT_NG is at CN7-4. It
should normally measure low, near zero V, relative to TP0, making LED3 on less
bright when voltage is correct. Also see PCB4 section for other ways to measure
INPUT_NG.
PCB5 places signal /Input Voltage OK (low) on CN11-15 (34 ckt ribbon) which
is J36-15 on CCM. (Measured relative to TP0 on PCB5 or TP1 on CCM). If
INPUT_NG is correct but /Input Voltage OK is high PCB5 is defective.
INPUT_NG is derived from VACIN which comes from PCB1 where the 3
phase input is rectified and divided (See section on Voltage Selection & Wrong
Voltage Detection for full explanation of how VACIN is derived) and goes to
CN2-1 on PCB3 where it is passed directly to PCB4 which is daughter board that
plugs into PCB3.
PCB1
VACIN can be measured at CN2-1 (+) and PGND on PCB3 (WK-5694). PGND
can be accessed easiest at CN1-1 on PCB3. It is also present at CN2-2. Note,
CN2 must be connected while taking this measurement.
It should be between 7.7 to 9.5V for 460 VAC or 3.5 to 4.7 V for 208-230 VAC
Power. For units with 400V input voltage (CE & CCC units) VACIN ranges
from 6.25 to 8.25V. 600V?
If 3 phase power of proper voltage is connected to the power supply and VACIN
is not within the values above, or is zero, PCB1 or connections to it may be
defective.
R1 on PCB4 is in parallel with R11 on PCB1. It is also possible (but less
likely) that if there was an open connection where PCB4 plugs into PCB3 or an
open trace on PCB3 or 4 so that R1 wasn’t connected then VACIN could be a
little higher expected. If the connection between CN2-2 on PCB1 to CN2 on
PCB3 is open VACIN may be a lot higher.
PCB4
If VACIN is correct and you know the inverters are configured correctly you
can quickly test PCB4 by removing CN7 from PCB4. If the contactors now close
PCB4 was defective.
The signal INPUT_NG going from CN7-4 on PCB4 to CN7-4 on PCB5 should
normally be false (low, near zero,) relative to TP0 on PCB5. You can also
measure from CN7-3 (+) to CN7-4 (-) on either PCB4 or PCB5. In this case if
INPUT_NG is false, the normal condition, you should measure +15V. If PCB4
is making INPUT_NG true then the opto isolator on PCB4 is on connecting +15V
on CN7-3 to CN7-4 making INPUT_NG high relative to TP0. Removing CN7
removes the high. If VACIN was in the correct range but INPUT_NG is true then
PCB4 is defective.
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CCM
If code 2-2 occurred with Start applied, CCM will latch the code until Start is
removed and reapplied. To be sure the code is not latched, remove Start, shut off
power supply then turn it back on. PCB5 places signal Input Voltage OK (low)
on CN11-15 (34 ckt ribbon) which is J36-15 on CCM. If, after following steps
above, this signal is low and code 2-2 is flashing CCM may defective. It is also
possible, as explained earlier in this section, that the CCM and the rest of the
system are responding correctly to transient dropouts or surges.
2-3
Power Supply Overheated.
Inverter module(s) and pilot regulator (chopper) module have sensors
monitoring their temperature. An over temperature in either inverter, chopper or
torch coolant will turn on the front panel TEMP indicator however the torch
coolant system over temperature sets a different code.
Because the unit is 100% duty cycle it should never see an over temperature in
normal operation.
Causes for 2-3 code:
 Harness for CN12 on PCB5 plugged into CN17
 Failed fan
 Defective inverter or chopper module
 Defective power supply PCB
 Defective CCM
CN12
CN17 not used is some units. It is the same size and is right next to CN12. If
PCB5 has been replaced it can be plugged into CN17 by mistake. This will show
2-3 code immediately at power on before the unit has been operated.
Inverter Fans
Power supplies have one (100A) two (150/200A) or three (300A) inverters.
Each inverter has a 24 VDC fan powered from a supply local to that inverter.
Inverter fans come on a few seconds after input power is applied. The delay is to
allow system to verify correct input voltage. Once on, the fans will run until there
has been no activity, no Start applied, no pilot or cut, for 7-8 minutes then the fan
control circuit will shut them off. Applying Start will turn fans back on. When
troubleshooting, turn power off then back on to be sure fan control circuit has not
timed out.
Check for air flow out the front panel louvers (left side) in front each inverter.
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INV #1
INV #2
INV #3
If no or reduced flow, suspect failed fan. Fans can be inspected / replaced
without removing inverters. At the rear of the unit there are removable panels to
access the fans. Verify the suspected fan is not turning then shut off power,
disconnect the fan connector, turn power back on and measure for 24 VDC at the
connector. If voltage is present fan is defective. If no 24 VDC, inverter module is
defective.
Chopper (Pilot Regulator) Fan
Chopper fan runs continuously whenever unit has power, no timeout. Fan is
visible at the bottom front of the chopper module. Fan gets its 24 VDC power
from CN1 on WK-5750A, the larger of the two chopper boards. If voltage
present replace fan, if not replace chopper. Be extremely carious measuring this
as shorting the pins together with a meter probe will damage the board.
Chopper (Pilot Regulator) Over Temperature Signal
Chopper has temperature sensor that disables it if overheated. Units before early
2006 did not have signals connected to PCB5 so would not activate the front
panel LED, would just stop piloting until it cooled down.
Later units have harness from CN4-1 on Chopper PCB WK5754A to power
supply PCB5, WK5602A, CN17-1. Signal is normally high, goes low when
overheated. Lights LED4 (PCB5) to indicate chopper is overheated.
If the chopper is clearly not overheated, has been off long enough to cool down,
and still indicates over temperature, disconnect CN4. If over temperature
indication goes away chopper is defective. If it doesn’t, if LED4 on PCB5 is still
on, either the harness is shorted (unlikely) or PCB5 is defective.
Inverter
If the inverter fan is operating and inverter is still causing overtemp indication
it is likely the inverter is defective. However give it enough time cool of to be
sure.
Signal /TEMP_ERR from the inverters can be measured at CN6-14 (common
TP0 on PCB5) on PCB5, WK-5602A board. CN6 is 16 ckt ribbon cable. This
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signal, normally high, +15VDC, goes low if an inverter overheats. For units with
2 or 3 inverters these signals are in parallel.
To determine if the inverter (or which one, for units with more than one) is
causing the /TEMP_ERR signal, disconnect the ribbon connector from each
inverter one at a time. When code 2-3 goes away that will be the overheated or
defective inverter. If the ribbon cable is disconnected from all the inverters you
will still get an error but it should switch from 2-3 to 2-4 (inverter not ready)
when disconnected from the inverter that causes the temperature error.
Ribbon Cable Shorted
If temperature error remains after disconnecting cable from all the inverters
problem may be a shorted ribbon cable or defective PCB5 or CCM. Remove
ribbon cable from J6 on PCB5 should change error from 2-3 to 2-4 if the ribbon
cable is at fault.
Power Supply PCB
PCB5, WK-5602A, takes the signal /TEMP_ERR from the inverters on CN614, combines it with signal CHOPPER_TEMP_ERR (units after early 2006) and
inverts it becoming signal /TEMP OK which is sent to the CCM on CN11-8 (J368 on CCM). Signal is low when temperature is OK. If, with the ribbon cable
disconnect from CN6 on PCB5 and the harness from the chopper (if present)
disconnected from CN17, the signal on CN11-8 is not low PCB5 is defective.
CCM
Signal /TEMP OK on J36-8 is active low. If it is low but code 2-3 and the front
panel Temp LED remain on then CCM is defective.
2-4
Power Supply Not Ready
2-4 is set when the signal /READY TO OPERATE, normally active low, is not
true. It is not true during the first few seconds after power on while the input
capacitors are being charged, a time called inrush. /READY TO OPERATE is
also false if the capacitors do not charge up during inrush or if the charge too
high. Missing phase also makes /READY TO OPERATE false but will set the
missing phase code 2-1 instead.
Causes for code 2-4:
 16 ckt ribbon cable disconnected from CN6 on either PCB5 or inverter.
 Contactor MC1 defective so no power to inverter or CN9 on PCB5
disconnected so inverter(s) get no power.
 PCB4, Detector PCB, defective
 PCB7, Relay PCB, defective.
 Inverter defective.
 PCB5 defective.
 CCM defective
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The power supply includes circuits to determine if the inverters are properly
configured for the input voltage that is being applied. Each inverter has a Voltage
Change PCB with 2 headers, CN1 & CN2. CN1 has jumper betweens pins 1 & 2,
CN2 between pins 3 & 4. A harness connector plugs into one of them on each
inverter, CN1 if configured for 230V or CN2 for 460V. The other end of the
harness connects to CN4 on PCB4. The harness is arranged so that a circuit is
completed when each inverter is configured for the same voltage. If neither the
230 or the 460 circuit is completed as is the case if one inverter is set for a
different voltage than the other, then a signal INPUT NG is sent to PCB5. The
simplified schematic below shows when there are 2 inverters but with a third
inverter it is similar.
T
100A INVERTER MODULE # 1 (Top)
CN2-460V
N (-)
V Change PCB
S
4
2
2
1
3
1
3
P (+)
4
3
2
1
4
CN1-230V
CN4 - PCB12
R
460
230
COM
CN6
T
100A INVERTER MODULE # 2 (bottom)
N (-)
V Change PCB
S
4
2
3
1
2
1
3
4
3
2
1
4
CN1-230V
CN4 - PCB12
R
CN6
P (+)
4
3
2
3
CN4
1
COM
RY6
+
230V
CN6
WK-5604
5
4
3
2
2
1
CN7
5
4
3
2
CN3
2
1
CN2
RY5
+12VDC
1
CN10
T1
CN6
CN5
DETECTOR PCB
+12VDC
FROM
AC INPUT
CN5
CN1
PCB4
+12VDC
RY 2
CN4
1
230
2
CN2
1
460
COM_A
230_A
460_A
CN2-460V
0___
TB3
220
230V
+
TB4
RY1
TB5
460V
460
CN9
230_A
COM_A
1
2
3
460
230
COM
+
460_A
RY2
CN10
1
2
3
460
230
COM
PCB7 WK-5628
RELAY PCB
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Ribbon Cable disconnected or open.
Even though INV_READY is open collector, normally high, the ribbon cable
must be connected to CN6 on PCB5 and at least one inverter or INV_READY
signal will be false. The reason is CN6 -10 on PCB5 must be pulled low by one
of the inverters or a circuit on PCB5 will pull INV_READY low. If pin 10 of the
ribbon cable is open that will cause INV_READY to be false.
Contactors
If there are 2 or 3 inverters, a single defective contactor will not cause 2-4 code
as the remaining inverters that are getting power will satisfy the INV_READY
signal.
Measure for 110 VAC on contactor coil. If present and contactor is not
energized then contactor is defective. If 110 VAC is not present, either PCB5 is
bad or no 110 VAC from T1 transformer.
PCB4 or PCB7
If unit has 2 or 3 inverters first determine which inverter is causing /READY
TO OPERATE to be false. With two or three inverters you can disconnect
ribbon cable from CN6 of one inverter at a time (other ones remain connected).
When 2-4 code goes away that is the inverter signaling the fault. Now you have to
determine if it is a PCB or the inverter causing the problem.
PCB4, Detector PCB
When configured for high voltage range (400, 460, 600V) a jumper in the
connector CN2 on the voltage change PCB (connects to CN4 on PCB4) of the top
inverter energizes relay RY2 on PCB4 (daughter board plugged into PCB3). The
normally open contact of RY2 becomes closed sending signal out from CN2-1 &
3 (PCB4) to CN4 on inverter PCB12. This tells the inverter that it is configured
for high range. Inverter then measures the incoming voltage to determine if it is
within expected value for high range. In low range RY2 is not energized and it’s
normally closed contact is across CN2-1 & 2 telling inverter it is configured for
208-230V. An open or intermittent connection of either the relay contact or the
harnesses (CN2 or CN4 of PCB4) will prevent the inverter from recognizing that
it is connected to the correct voltage so it will make /READY TO OPERATE
false.
PCB4 also supplies +12V on CN3-1 and another normally open contact of
RY2 applies ground to CN3-2 if RY2 is energized (high input voltage range).
This energizes relay RY2 on PCB7, the Relay board.
PCB7, Relay PCB
If unit has 2 or 3 inverters and either the second or third one has been
determined to cause the /READY TO OPERATE to be false then problem may be
PCB7 or harnesses connected to it.
As explained above if inverters are configured for high range (400, 460,
600V), relay RY2 (PCB7) is energized so it’s normally open contacts close the
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connection between CN9-1 & 3 and CN10-1 & 3 sending signal to second and
third inverters if thy are present. An open or intermittent connection of either the
relay contact or the harnesses on PCB7 (CN2 to energize RY2 or CN9 or 10
sending signal to inverter) will prevent the inverter from recognizing that it is
connected to the correct voltage so it will make /READY TO OPERATE false
and set the 2-4 code.
If inverters are configured for low input voltage range then RY2 is not
energized so it’s normally closed contacts make connection between CN9-2 & 3
and CN10-2 & 3. Intermittent or open of the NC contacts or the wire harness on
CN9 or CN10 can cause /READY TO OPERATE to be false and set the 2-4 code.
Inverter
The active low signal /READY TO OPERATE comes from PCB5 and is sent
to the CCM on J36-13 (34 ckt ribbon cable).
Signal INV_READY comes from the inverter(s) as an active high (open
collector) on CN6-8 (16 ckt. ribbon) to PCB5, WK-5602A. Any inverter can pull
the line low if it is not ready.
On PCB5 the active high signal is inverted to become active low signal /READY
TO OPERATE. /READY TO OPERATE is sent to the CCM on J36-13.
For the first few seconds after power is turned on, a timer, IC17, on the
inverter PCB13 keeps CN6-10 high. This in turn forces INV_READY low and
/READY TO OPERATE high.. This allows time for the input capacitors to charge
up through the inrush resistors. Then after a few seconds, IC17 times out holding
CN6-10 low.
If the capacitors have not reached proper voltage at the end of the inrush time
will set code 2-4. It will also light an LED3, DCV_ERR on PCB13 of the
defective inverter. This can happen if the inrush resistors (R1 & 2 on the inverter
module ) are open of disconnected (CN4 on PCB 9).
If the contactor is on, supplying power to the inverter, measure the
INV_READY signal at CN6-8 (TP0 on PCB5 common) normally +15VDC. Also
measure J6-10 which should be low. If either are wrong, inverter is defective.
If there are two or three inverters you can disconnect ribbon cable from CN6 of
one inverter at a time (other ones remain connected). When 2-4 code goes away
that was the bad inverter.
PCB5 & CCM
If CN6-8 is high, +15VDC, and CN6-10 is low then measure J36-13 on CCM
(CCM TP1 common). If J36-13 is low then CCM is defective. If it’s high PCB5
is bad.
Code 2-4 combined with 3-4 & 4-2 when the Plasma Enable on the GCM 2000
or 2010 gas control is set to disable can indicate a fault in the CCM I/O PCB.
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When switching back to Enabled the pump will not restart so continues to display
4-2 indicating no coolant flowing.
Normally the code during a disable should be 1-1. Circuits on the I/O PCB
detect the Plasma Enable is disabled and send signal to the microcontroller in the
CCM. If that signal doesn’t get passed the microcontroller doesn’t know system is
disabled so sets these 3 codes.
2-5
DC Output Low
Immediately after receiving Start signal from CNC, inverters are enabled and
CCM measures the power supply output voltage between negative (Torch) to
positive (Work) at the output busbars. If this is less than a set value during
preflow or if at any time during piloting or cutting it drops to below that value for
a short time, code 2-5 is set. Currently that value is -60V.
Code 2-5 remains set (latched) after Start is removed to indicate why unit
stopped. Code is cleared next time Start is applied (if fault has been removed) or
when power is turned off.
Causes for 2-5 code set before pilot ignition:
 J6 on CCM not connected (CCM connection to DC Output Voltage) or
open connection.
 CN1 & CN14 reversed on PCB5
 Shorted Pilot Regulator (chopper).
 Inverter not getting Start signals (START & START2) from CCM.
 Inverter defective.
Causes for 2-5 code set during pilot or cut:
 No or low Preflow or Plasma gas flow.
J6 connection open
The connection from J6-8 to the Work busbar has a small inductor spliced into
the wire. If this inductor is open CCM will not detect output voltage. Check
continuity from J6-8 to Work busbar, should be less than 100 ohms.
Test for shorted chopper.
 First turn off input power and jumper across diode D2 (mounted on the
chassis to the rear of the chopper). Leave jumper on for a couple minutes
to insure chopper capacitors bleed down to zero volts.
 Chopper freewheel diodes. Measure resistance between TB2 and TB4 on
chopper. Expect to see over 20K ohms with it slowly increasing as it
charges a capacitor. If using a meter with a diode scale expect to see
continuity one way (diode forward biased) and open with probes reversed.
A low resistance with either method indicates a short.
 Chopper IGBTs. Measure resistance TB1 to TB4 on chopper. Should be
open circuit. . If using a meter with a diode scale expect to see continuity
one way (diode forward biased) and open with probes reversed. A low
resistance with either method indicates a short.
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Inverter Start signals
CCM has redundant start signals, START, CCM J35-7 (26 ckt ribbon), and
START2, CCM J35-6, to insure start can be removed in case of a fault in one of
the start circuits. The signal START2, should be present, active low, anytime
CNC START is applied. If there is a fault, such as low DC Voltage, START is
immediately removed. We know CNC START is getting to CCM else code 2-5
wouldn’t be set.
Measure START2. Apply CNC START (J15-3 & 4 or jumper TB1-5 & 6) and
measure for low on J35-7 (CCM TP1 common). If high, about +10 VDC, CCM is
defective.
Measure START. Apply CNC START (J15-3 & 4 or jumper TB1-5 & 6) and
measure for a momentary low on J35-6 (CCM TP1 common). This may be
difficult to detect on a meter as it is only low for about 150 ms. If J35-6 does not
go low even momentarily but remains high at about +10 VDC, CCM is defective.
Another way to test for START is to temporarily jumper J35-6 to TP1 (CCM)
and apply CNC START. If inverter(s) come on, front panel DC LED on, no 2-5
code, then CCM is defective.
Inverter Defective.
A number of possible failures could cause no or low DC from the inverter.
Shorted output diodes. It is normal to measure 10K-20K ohms across the output,
plus to minus, of the inverters when their output cables are connected. If it is
much less, like a few ohms, one of the inverters is likely shorted. Remove either
positive or negative cables from inverter(s) output and confirm inverter still
measures shorted. If more than one inverter, disconnect and measure each one to
find the defective one(s).
Inverter no output
Disconnect arcstarter cable (so HF can’t fire) from J59 on the power supply
rear panel. Connect voltmeter between busbars under the cover on the rear panel
where the Torch (negative) and Work (positive) leads connect. Attempt to start
the unit. You would normally see 300-400 volts. It may only be there for a
second. If no voltage inverter is defective. If both Start signals are present and
no DC output, the inverter defective.
Gas Flow refer to section on Gas Controls.
2-6
AC Input Over Current
Each power supply inverter module contains two inverter sections which are in
parallel for 208 & 230V or in series for 400, 460 & 600V. Each inverter section
monitors its input current draw. If either section exceeds normal levels, the
inverter latches the signal /OCR, disables the START input inside the inverter and
sends /OCR to PCB5 on CN6-12. PCB5 sends Signal Inverter OCR to CCM on
J36-16.
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/OCR from the inverter is latched in the inverter, only way to reset it is to
remove power.
Causes for 2-6 code:
 Cut demand signal to power supply exceeds 10V due to:
o Remote Analog Demand signal greater than 10V.
o Defective CCM
o Defective PCB5
 Defective inverter.
 Defective PCB5
 Defective CCM
Cut Demand from CCM may be measured at TP13 on CCM I/O PCB (TP1
common) or J35-2. Before CNC START, Cut Demand is set to zero, if it is other
than zero CCM is defective.
After receiving CNC START and during preflow Cut demand is set to a lower
starting level (varies with output current setting and MAX current capacity of the
unit) generally between 0.5 to 3.5 volts. Upon arc transfer Cut Demand ramps up
to cutting level with a MAX of 10 VDC if current is set to MAX output.
It is likely if a CCM fault causing code 2-6 occurs it will be in hardware that
makes the demand a constant level, over 10V. However if the demand is normal
during pilot, then ramps too high, OCR will likely occur to quickly to see with a
meter, will require an oscilloscope.
Cut Demand PCB5 WK-5602
Do not make measurements on WK-5602 board with HF firing. Noise may be
introduced than can cause catastrophic inverter failure. Instead use following
method:
To measure demand signals without introducing HF noise disconnect the RAS
(Remote Arc Starter) control cable at the RAS end, J58, so the pilot doesn’t start.
At the end of preflow CCM will attempt to ignite pilot for 15 sec. (Because
pilot won’t ignite, status code 1-2 will flash on power supply front panel). The
CCM will apply the Pilot Demand and Cut Demand for preflow time (default 2
sec but can be increased up to 8 sec if more time is needed) plus 15 sec. ignition
time giving enough time to measure with voltmeter.
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Some of these values are preliminary and may change a little with later CCM
revisions.
Cut Current
0-10
11-25
26-35
36-55
56-75
76-105
106-135
136-155
156-210
211-300
Initial Cut Demand -- Chopper Pilot Systems
100A
150A
200A
300A
SYS
SYS
SYS
SYS
1.5
1.0
0.8
0.5
1.7
1.1
0.8
0.6
2.0
1.3
1.0
0.6
2.4
1.6
1.2
0.8
2..5
1.6
1.2
0.8
2.6
1.7
1.3
0.9
1.8
1.4
0.9
2.0
1.5
1.0
1.5
1.0
1.0
Some early power supplies have pilot resistor(s) instead of chopper regulators.
For those units Initial Cut Demand will be slightly higher.
Cut Demand leaves CCM I/O PCB from J35-2 (26 ckt ribbon cable) and goes
to CN10 (other end of ribbon cable) on PCB5, WK-5602A. Cut demand is
filtered, scaled to 80% of input (100, 200, & 300A) or 60% (150A) and renamed
as I_REF. I_REF is sent to the inverter module(s) on CN6-2 (16 ckt ribbon
cable).
I_REF should be 80% of Cut Demand if unit is 100, 200 or 300A. If unit is 150A,
I_REF is 60% of Cut Demand .
For example, 150A power supply set for 100A out. Initial cut demand should
1.7V, I_REF at CN6-2 should be 1.7 * 0.6 =1V. If it had been a 100A unit set
for 100A Cut Demand would be 2.6V and I_REF should be 2.6 * 0.8 = 2.1V.
If this is not correct PCB5 is defective.
Inverter
If I_REF as measured above is correct, the inverter may be faulty causing the
2-6 code.
Signal /OCR is applied in parallel from each inverter on CN6-12 (TP0
common). If an actual over current occurred the inverter latches this line low
until power is recycled. If, while cutting, this line went low for some other
reason, even momentarily, the CCM will stop the cut and latch the 2-6 code even
if the OCR line went back high. To see if this is the case, momentarily apply
CNC START just long enough to start preflow then remove it. This will allow the
CCM to unlatch the code.
If momentarily applying START does remove the code, possible causes in the
inverter are the ribbon cable not locked into its connector either on PCB5 or one
of the inverters. Also loose connection on one of the following connectors in the
inverter: Connectors that could be involved are CN1, CN2 CN33, on PCB13; CN3, CN5,
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CN7, CN33 on PCB1; CN1, CN4, CN5 on PCB12. If cannot be resolved replace the
inverter.
If momentarily applying START does not remove the 2-6 code then one of the
inverters may be have latched the /OCR line (CN6-12) low. If this line is not low
then go to section on PCB5 & CCM.
If CN6-12 is low and there is more than one inverter module, you have to
determine which one has set the /OCR signal. Because each inverter is connected
in parallel to the ribbon cable’s /OCR line, the only way to tell which one is
holding the line low is to disconnect them one at a time. Because the /OCR is
reset when power is removed, the ribbon cable (CN6 on each inverter) must be
disconnected with power on. Be very careful!
If the first one removed is not the cause, plug it back in otherwise when the
last one is removed you will set code 2-4, Power Supply Not Ready. It takes a
couple seconds for the CCM to recognize the fault is removed and clear the fault
so after removing each CN6 give it enough time to clear before deciding if you
found the bad one.
If none of the inverters appear to holding the CN6-12 low then the ribbon
cable nay be shorted.
PCB5 /OCR
Having determined above that CN6-12 (TP0 common) is high but 2-6 code
remains after momentarily applying START then either PCB5 or CCM is
defective. Signal Inverter OCR is sent to CCM on J36-16. If CN6-12 is not low
and J36-16 is low PCB5 is defective or the 34 ckt ribbon cable is shorted.
CCM
If J35-16 is not low but code 2-6 is still flashing then CCM is defective.
2-7
Unwanted Current
As soon as CNC Start is on, the inverters are turned on and should be
producing open circuit voltage (OCV). There should be no output current at this
time because without pilot ignition there should be no path for current.
Power supply monitors for current using current sensors HCT1 on the output
of the chopper module (or on the pilot buss bar for early resistor pilot units) and
HCT2 on the Work buss bar. System performs 3 tests for unwanted current. Two
are for current on either the pilot circuit (sets code 2-8) or Work cable (sets code
2-9) as indicated by digital signals Pilot ON and Arc Transferred.
The third test uses the analog output (sum of the two current sensors) and if
analog signal indicates over 20A set code 2-7. CCM software prior to version 2.1
looks at the analog signal first (2-7) then the pilot and work digital signals (2-8 &
2-9). Result of this is most unwanted currents faults will set 2-7 which doesn’t
indicate if fault is in pilot or work. Starting with software version 2.1 we switched
the order so the digital signals (codes 2-8 & 2-9) are looked at first followed by
the analog signal. In most cases this should isolate the fault quicker.
After version 2.1 any faults that set 2-7 should be limited to defective PCBs.
Actual shorts should set codes 2-8 or 2-9.
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Code 2-7 If current over about 20A is detected during preflow, before pilot
ignition, CCM blocks ignition, shuts off the inverters, turns off the pilot contactor
and chopper, and sets code 2-7. Code is latched so you can determine what
caused shutdown after Start is removed. Code is reset next time CNC Start is
applied (assuming fault is corrected).
Causes for code 2-7 (Software prior to version 2.1):
 Short between power supply negative output (TORCH terminal on back of
power supply) and pilot circuit.
 Short between power supply negative output and Work circuit.
 Short between power supply negative output and earth ground.
 Defective of incorrectly installed user supplied equipment such as torch
height controls that make connections to power supply output.
 Defective pilot or work current sensors.
 Defective PCB5
 Defective CCM

Causes for code 2-7 (Software version 2.1 and later):
 Defective PCB5
 Defective CCM
For troubleshooting code 2-7 with software prior to version 2.1 got to Troubleshooting
Unwanted Current Faults and start the beginning.
For troubleshooting code 2-7 with software version 2.1 or later got to Troubleshooting
Unwanted Current Faults sections on PCB5 and CCM.
2-8
Unwanted Pilot Current Signal
As soon as CNC Start is on, the inverters are turned on and should be
producing open circuit voltage (OCV). There should be no output current at this
time because without pilot ignition there should be no path for current. Power
supply monitors for current using current sensors HCT1 on the output of the
chopper module (or on the pilot buss bar for early resistor pilot units). If any
current (more than about 5A) is detected during preflow, before pilot ignition,
CCM blocks ignition, shuts off the inverters, turns off the pilot contactor and
chopper, and sets code 2-8. Code is latched so you can determine what caused
shutdown after Start is removed. Code is reset next time CNC Start is applied
(assuming fault is corrected).
Causes for code 2-8:
 Short between electrode and tip due to mismatch of consumables or
foreign matter between tip and electrode.
 Shorted torch body.
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




Short between power supply negative output (TORCH terminal on back of
power supply) and pilot circuit..
Defective of incorrectly installed user supplied equipment such as torch
height controls that make connections to power supply output.
Defective pilot current sensor.
Defective PCB5
Defective CCM
Refer to section: Troubleshooting Unwanted Current Faults (codes 2-7, 2-8, 2-9)
following section 2-9 to troubleshoot.
2-9
Unwanted Transfer Signal
As soon as CNC Start is on, the inverters are turned on and should be
producing open circuit voltage (OCV). There should be no output current at this
time because without pilot ignition there should be no path for current. Power
supply monitors for work lead current using current sensor HCT2 on the Work
buss bar. If any current is detected during preflow, before pilot ignition, CCM
blocks ignition, shuts off the inverters, turns off the pilot contactor and chopper,
and sets code 2-8. Code is latched so you can determine what caused shutdown
after Start is removed. Code is reset next time CNC Start is applied (assuming
fault is corrected).






Short between power supply negative output and Work circuit.
Short between power supply negative output and earth ground.
Defective or incorrectly installed user supplied equipment such as torch
height controls that make connections to power supply output.
Defective work current sensor.
Defective PCB5
Defective CCM
Troubleshooting Unwanted Current Faults (codes 2-7, 2-8, 2-9):
1. Code appears immediately following the power-on purge and before START is
applied then the fault is most likely a defect in the associated current sensor
circuit:
Code 2-8:
The pilot current sensor, HCT1, part of the Chopper module, gets + & - supply
voltage from the chopper. If the minus supply is missing the sensor becomes
unbalanced and will have an output that indicating pilot current even when there
is none. To troubleshoot, start by disconnecting harness from CN5 on chopper
PCB2, WK-5754. Turn power supply on and if code 2-8 does not appear fault is
in the chopper module. Check for any connectors loose or wires pulled out of
connectors on either of the chopper PCBs. If none found replace the chopper.
Look to descriptions for Current Sensors or PCB5 later in this section for more
details.
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Code 2-9:
The work lead sensor, HCT2, gets +&- voltage supply and sends its output
signal to PCB5 via CN4. If the minus supply is missing the sensor becomes
unbalanced and will have an output that indicating work current even when there
is none. To troubleshoot, start by disconnecting CN4 from PCB5. If 2-9 code no
longer present at power up fault likely in sensor, it’s harness or PCB5. Look to
descriptions for Current Sensors or PCB5 later in this section for more details.
Code 2-7:
It is unlikely that code 2-7 will appear here but if it does follow steps for both
2-8 and 2-9.
2. Codes that do not appear until Start signal is applied are likely from an actual
current being detected during prefow when there should not be current.
First determine if problem is outside of power or inside. Code 2-9 disconnect
negative (Torch) or code 2-8 disconnect pilot cables from back of power supply.
For code 2-7 disconnect both. Disconnect control cable from J58 on the arcstarter
to prevent HF firing while troubleshooting.
In this condition unit will not pilot but upon applying CNC START system
should go through Preflow and attempt to turn on HF in arcstarter for 15 seconds
before setting code 1-2 because pilot did not start. HF will not turn on because
RHF control cable is removed.
If this happens, problem is outside the power supply. For Autocut units with
GCM 1000, even though the GCM 1000 is mounted on the power supply, it is
considered outside the supply. If it still sets code 2-7, 2-8 or 2-9 problem is inside
power supply or in user installed equipment.
Shorts outside the power supply
Reconnect the negative and/or pilot leads at the rear of the power supply. It’s
highly unlikely to have short between the negative (Torch) cable and the Pilot
cable or Work cable between the power supply and RAS. The only possibility is
if the insulation of the negative cable had worn or burnt so it contacts the table
(work) or if both negative and pilot cable have been worn or burnt and are
touching each other. Inspect the cable insulation for any place it may be worn or
burned through allowing contact with the table.
Most likely this short is in the arcstarter or the torch head or consumable parts.
 Inspect the torch consumables, make sure all parts are in place and are the
correct numbers and there is no foreign matter between them.

Disconnect and insulate torch lead pilot wire in the RAS. The pilot wire
from the torch, not the cable that goes to the power supply. Disconnect
the RAS control cable from the RAS. Attempt to start torch. If still get
code 2-7 short is in RAS.
o Inspect for physical shorts, wires that have been disconnected or
broken, etc.
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o Shorted capacitor on RAS Capacitor PCB. Measure for short from
NEG fast-on (spade) terminal to PLT terminal and to chassis.

If do not get code 2-7 after disconnecting the pilot wire, the problem is in
the torch leads or torch head. Only place the pilot wire can contact the
negative in the torch leads is at the ends. You can easily inspect the RAS
end but have to remove the torch mounting tube to see the torch end
connections. If no shorts evident here replace the torch head. You can try
to measure for a short with a meter but shorts can be a carbon path that has
too much resistance to be detected with a meter but still carry current
when subjected to a couple hundred volts.
Shorts inside the power supply
For a short inside the power supply to cause current to be detected by the Pilot
or Work lead current sensors the short has to on the output side of the sensor and
shorted to something, such as the negative (Torch) terminal. Possibilities are:
o Blue wire from Work buss bar to CN2-1 on PCB8 (WK-5687).
Disconnect CN2 on PCB8, Apply CNC START. If no code 2-7
replace PCB8.
o Red wire from Pilot buss bar CN3 on PCB8 (WK-5687). Disconnect
CN3 on PCB8, Apply CNC START. If no code 2-7 replace PCB8.
o Black wire on Work buss bar, red wire from pilot buss bar and blue
wire from Negative buss bar go to J6 on CCM. Highly unlikely there
could be a short here but inspect the wires and look arcing on or under
the J6 connector. You cannot test this by disconnecting J6 or the black
and blue wires as this will set the 2-5, DC Output Low code which
gets set first.
o User installed equipment.
User Installed Equipment
For user installed equipment to cause 2-7 code it would have to be connected
on the output (to the rear) of the current sensors. To test, disconnect user
equipment and apply CNC START. If code 2-7 is gone user equipment was
defective or connected incorrectly.
Current sensors
Current sensors HCT1 & 2 are Hall Effect linear current sensors. Their
voltage supply, + and – 15 VDC, and their outputs are connected to CN3 (pilot)
and CN4 (work) on PCB5,WK-5602A. With unit turned on and in idle (Start not
on) measure CN3-3 and CN4-3 (PCB5 TP0 common) for zero volts. If not zero,
check for +15 VDC on pin 1 and -15 VDC on pin 2 of each connector on the
harness that plugs into the sensor. Pin 4 of each connector is common. If +/- 15
VDC OK, sensor whose output is not zero is defective. If +/- 15 VDC is not OK
see section on system bias supply.
PCB5
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PCB5 puts out active low signal, “/Arc Transferred”, on CN11-3 (J36-3) when
there is current measured in the Work lead and active low signal “/Pilot ON” on
CN11-4 (J36-4) when current is detected in the Pilot output. During idle, when
CNC START is not on, these signals should be high (+15 VDC). If code is 2-8,
check for +15 VDC at J36-4 (common TP1 on CCM). ). If code is 2-9, check for
+15 VDC at J36-3 (common TP1 on CCM). If either of these is low, PCB5 may
be defective.
o Code 2-8 or 2-9:
Check for + 15 VDC at TP2 and – 15 VDC at TP3 (TP0 common) on
PCB5. The +& - 15 VDC measured above when checking the current
sensors comes from this board so if you checked it above not necessary to
do so again. If voltages are OK, PCB5 is bad. If either voltage is missing
see section on system bias supply.
o Code 2-7:
PCB5 also takes the analog signal from each sensor, adds them and puts
out signal Output Current on CN11-1 (J36-1), an analog signal on whose
level is scaled 0-10V = zero to power supply MAX amps. During idle and
preflow signal here should be 0 VDC, if not PCB5 is bad.
CCM
If signals “/Arc Transferred” and “/Pilot ON” were high above and the
analog Output Current signal is zero V. and CCM still causes code 2-7, 28 or 2-9 CCM is defective.
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Group 3, Gas Control Codes.
Also refer to Gas Control Status Codes at the end of this section.
3-1
Gas Control Communication Fault
No signal detected over the fiber optic link from the gas control. In the case
where there are additional other than Gas Control connected to the CANBUS this
code would indicate the Gas Control is having communication problems while the
other CANBUS devises are OK. We don’t currently have any other devises on
the CANBUS so it is more likely that code 5-1 will be what is set. In any case
troubleshooting is the same as for 5-1.
3-2
Gas Control communications reply fault
Communication has been established but Gas Control did not reply to a request
from the CCM in the time allowed. Likely cause is Fiber optic problems (see
code 5-1) or if problem persists defective Gas Control main PCB.
3-3
Gas Pressure fault
With GCM 1000 gas pressure sensor is on plasma gas only but is in series with
Run /Set SW. 3-3 code here indicates either plasma gas missing or very low
pressure, less than 50 PSI, or RUN/SET switch is in SET position.
Starting with GCM2010_AG or GCM2000_AC we measure inlet pressure of
both plasma and shield gas immediately gas selection manifold. If pressure is either
too low or too high it sets 3-3 code. Earlier revs should not display 3-3 code.
GCM2010 will display which gas is the problem and its actual pressure. With GCM
2000 you have to figure it out. The pressure at the point where it is measured
should be in the range of 100-135 PSI. Except for shield gas if the Gas SW is set to
pressure then the min pressure can be 85 PSI.
In the Gas Control, on the main PCB, measure between test points TP1 (gnd)
and TP18 (shield) and TP19 (plasma) to measure the output of the pressure sensors.
Voltage should be between 2.6V to 3.5V for 100-135 PSI. With shield SW set to
pressure low limit is 2.1V. Whichever gas is outside those limits will be the one
causing the fault. Remember the pressure may drop during operation, set the code,
then recover when you are measuring it.
3-4
Gas Control not ready
Code 3-4 combined with 2-4 & 4-2 when the Plasma Enable on the GCM 2000
or 2010 gas control is set to disable can indicate a fault in the CCM I/O PCB.
When switching back to Enabled the pump will not restart so continues to display
4-2 indicating no coolant flowing.
Normally the code during a disable should be 1-1. Circuits on the I/O PCB
detect the Plasma Enable is disabled and send signal to the microcontroller in the
CCM. If that signal doesn’t get passed the microcontroller doesn’t know the
system is disabled so it sets these other 3 codes.
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3-5
Gas Control Protocol Error
Application error or firmware incompatibility fault. Consult factory for latest
firmware update.
3-6
Invalid Current Control level from Gas Control
When CCM requests the output current setting Gas Control it returned a value
outside the range available from the power supply. Most likely cause is a firmware
incompatibility problem. Consult factory for latest firmware update.
3-7
Gas Control returns wrong command sequence.
Firmware incompatibility. Consult factory for latest firmware update.
3-8
Mismatch between the CCM and gas control type.
One is for Autocut while the other is an Ultracut.
 The GCM 2000 and GCM 2010 use the same main PCB. For the GCM 2000
there is a jumper between J10-4 and J802-2 which configures the program for
the GCM 2000. If that jumper is missing you will get the 3-8 code even
though both Gas Control and CCM are for Autocut.
3-9
Gas Control Communication reply fault.
Rely doesn’t match what was requested. Firmware incompatibility. Consult
factory for latest firmware update.
3-10 Warning -- Gas Control Firmware (the program) is not up to same level as
the CCM. System will work but may not be optimized for consumable best
consumable life. Consult factory for latest firmware update.
GCM 2000 & 2010 Status Codes
GCM 2000 has an LED on the front panel which blinks various codes.
GCM 2000 Status LED Codes
0
1
2
3
4
5
6
Indication
LED on steady.
LED blinks steady
½ sec on, 1/3 sec off
LED blinks twice followed
by 2 sec off then repeats
LED blinks 3 times followed
by 2 sec off then repeats
LED blinks 4 times followed
by 2 sec off then repeats
LED blinks 5 times followed
by 2 sec off then repeats
LED blinks 6 times followed
by 2 sec off then repeats
Explanation
Gas Control Cutting or Ready to Cut
Gas Control is Purging; Mode SW not set to RUN;
Gas Select SW fault.
Plasma Enable SW is set to Disable
Inlet Gas Pressure is out of range
CAN bus communication error - unacknowledged
message
CAN bus communication error – bus off
CAN bus communication error – bus timed out.
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GCM 2010 has LCD display which displays many of the Status messages however there
a few relating to communications that aren’t clear.
When there is a communication error it will be displayed but once it has recovered the
display will show what the error was by displaying:
^E4 – Low level CAN bus error where the CCM did not acknowledge receiving a
message from the Gas Control.
^E5 – Low level CAN bus error where the bus is off.
^E6 – CAN bus communication (the fiber optic) has timed out.
Coolant System Codes
4-1
Coolant Level
Coolant level SW, in the top of the coolant tank, is normally closed, opens
when level is above approximately ½ full. Signal from SW goes to CN14 on
PCB5. Output of PCB5 is on CN11, 34 ckt. ribbon cable that goes to CCM J36.
Possible causes of low coolant code (other than low coolant) are:
 Defective level SW
 Wiring
 PCB5
 CCM
Defective level SW – Disconnect connector at level SW. If the low level code
goes away the level sensor is defective. You can operate with the sensor
disconnected but until you can replace it but won’t be warned if the coolant is
actually low.
PCB5 – Level SW connects to PCB5 at CN14 pins 1 (signal) & 2 (gnd). Remove
CN14, if the 4-1 code goes away problem is in wiring between level SW and
connector. If code remains, Measure output of PCB5 on pin 10 of 34 ckt. ribbon
cable CN11/J36. If less than 1V PCB5 is faulty or ribbon cable pin 10 is shorted
to pin 9 or 11. Otherwise replace CCM.
If coolant really is low but system fails to detect it: Causes can be all of the above
plus connector on Level SW or CN14 on PCB5 disconnected.
When coolant is low a resistance reading between the two pins of level switch
connector should be a short. If open switch is defective.
4-2
Low or No Coolant Flow.
Coolant flow is detected by coolant sensor F1 located in the return plumbing
between the radiator and the upper inlet of the coolant tank. It is a turbine type
that puts out a pulse train whose frequency is relative to the flow. Frequency is
752 pulses per minute per liter. When not cutting, if flow is less 0.7 gal/min for
15 seconds it generates a fault.
When cutting, if flow is between 0.35 and 0.7 gal/min, for more than 3 sec or
less than 0.35 gal/min for any time at all it generates a fault.
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Coolant sensor received +5V (pin 1) and gnd (pin 3) from CN13 on PCB5.
Coolant Flow signal (frequency) is on pin 2. Signal is buffered on PCB5 and
passed to CCM on pin 6 of the 34 ckt. ribbon cable, CN11 to J36. Signal common
is pin 5 of the ribbon cable. Common is also available on at TP0 on PCB5 or TP1
on CCM I/O PCB.
No flow, either actual or failure to sense flow, is most likely to set code 4-4
unless something fails after power up purge. If flow sensor or PCB fails after
purge, you normally would try recycling power so again it would set 4-4.
Possible causes for low flow.
 Coolant filter (internal or external) clogged.
 Coolant supply or return hose twisted or pinched reducing flow.
If coolant flow in not low but code is being set, possible causes:
 Sensor disconnected
 Defective flow sensor
 PCB5
 CCM
See section code 4-4 for troubleshooting details.
Note -- Code 4-2 combined with 2-4 & 3-4 when the Plasma Enable on the
GCM 2000 or 2010 gas control is set to disable can indicate a fault in the CCM
I/O PCB. When switching back to Enabled the pump will not restart so continues
to display 4-2 indicating no coolant flowing.
Normally the code during a disable should be 1-1. Circuits on the I/O PCB
detect the Plasma Enable is disabled and send signal to the microcontroller in the
CCM. If that signal doesn’t get passed the microcontroller doesn’t know system is
disabled so sets these 3 codes.
4-3
Coolant Overheated
TH1 is a linear negative temperature coefficient resistor sensor attached to the
brass fitting where the torch coolant return enters the power supply rear panel.
It forms the upper part of a voltage divider.
PCB5
CN1
1
TH1
NTC
CN11 / J36
-
7
2
+
8
TP0
Reasons for coolant overheated:
 Coolant fan failed
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

Radiator fins clogged with dirt
Duty cycle exceeded (ambient temperature above 40 deg C and operating
at high duty cycle)
Coolant not overheated but code 4-3 still set:
 Coolant temperature sensor circuit open
 PCB5
 CCM
Failed fan – Check for 24 VDC at fan connector, if present replace fan.
Open Coolant sensor – Temperature sensor has leads about a foot long with a
connector which connects to a 2 wire harness going to PCB5 CN1. If either end is
not connected gives 4-3 fault.
Coolant sensor measures about 20-25K ohms at room temperature. Resistance
reduces as temperature goes up. If resistance measures considerably more than
25K the sensor is defective.
PCB5 – Voltage at CN1-1 should be +15VDC. At room temperature the voltage
at CN1-2 is about 2.5-3 VDC. It increases at higher coolant temperatures. Voltage
out of PCB5 on the CN11 / J36 pin 7 is about 1.5-2 VDC at room temp. It is
scaled by the circuits on PCB5 so that 0-10V = 0 to 100 deg C. If the sensor
measures the correct resistance and either voltage at CN1 or at CN11 / J36 is
wrong then PCB5 is defective.
CCM – If voltages are correct on PCB5 then the CCM is at fault.
4-4
Cooling System not Ready
When power is applied to the system with External E-Stop satisfied and Plasma
Power Supply Enabled (switch on GCM 2000, 2010 or remote HMI) system goes
into the purge state. During purge gasses flow and the coolant pump operates.
Pump runs for up to 30 seconds during which it must see flow greater than 0.35
gal/min for at least 5 seconds. If it does not, it sets 4-4 code. When first installing
a system or new (dry) torch leads it is normal to have this happen until coolant has
circulated throughout the system.
Reasons for Cooling System not Ready code.
Coolant not flowing:
 In new installation, coolant has not circulated all the way through the
leads.
 Coolant supply & return leads are reversed, check valve in torch coolant
return prevents reverse flow.
 Torch parts removed or are wrong style so torch check valve shuts off
flow.
 Torch coolant tube damaged.
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

No power to pump motor.
Pump/motor failure.
Coolant actually flows (for 30 sec. until pump shut off due to not sensing flow):
 Flow sensor disconnected or failed, see sect. code 4-2 for description of
flow sensor operation.
 PCB5
 CCM
Damaged Coolant Tube
Coolant tube includes a check valve at it’s upper end. When cartridge with
consumables is not installed the spring loaded coolant tube is fully extended
closing the check valve preventing coolant from leaking out.
When consumables are in place they push the tube inward, opening the check
valve, allowing coolant to flow. The coolant tube has fingers on the end to contact
the inside of the electrode and allow coolant to flow through the openings
between the fingers.
The fingers can be bent over or broken if reasonable care is not taken when the
cartridge is not in place. If the fingers are bent or broken it shortens the tube so
the consumables may not push the tube in enough to open the check valve
resulting on no coolant flow. The coolant tube assembly may be replaced separate
from the torch head.
Power to pump motor is 200 VAC from T1 transformer through CP7 rear panel
circuit breaker to CN3-1 & 3 on relay board PCB7. Relay RY3 on PCB7 turns on
power to CN4-1&3 going to the pump motor. Power for RY3 is +15 VDC
coming from PCB5 CN8-1 to PCB7 CN8-1. A low level from PCB5 CN8-2 to
on PCB7 CN8-2 turns on RY3.
PCB7 WK-5628
RELAY PCB
T1
200VAC
C.P7
CN3
RY4
CN20
1
1
1 1
2
2
2 2
3
3
3 3
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PUMP
.
MOT1
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Sensor disconnected – flow sensor comes with wire about 1 ft. long and a
connector that connects to a 3 wire harness. This could be disconnected or CN13
where the harness connects to PCB5 could be disconnected.
Defective Flow Sensor – If sensor is not putting out pulses it may be setting at
either +5V or 0 V. Measure for +5V on CN13-1 (common is TP0 on PCB5 or
TP1 on CCM) to confirm that the +5V supply is present. Then measure CN13-2.
The output of the sensor is a series of pulses which are best measured with an
oscilloscope however a voltmeter can be used as it will read an average
somewhere between the pulse peak and zero.
The no load output of the flow sensor is a series of rectangular pulses with
amplitude 0-5VDC. The output impedance is about 5K.
10K
CN13-2
5K
0-5V
On PCB5 it goes into a transistor with 10K base resistor so for the signal at
CN13-2 the 5V peak is loaded down to about 3V relative to TP0. If the flow
sensor is disconnected CN13-2 is zero V as there is no pull-up resistor.
Expect the normal signal at CN13-2 to be around 1-2V. The flow sensor
consists of an IR LED and photo transistor with a blade that breaks the light path
between the LED and photo transistor as it spins. If there is no flow one would
either measure zero V or 3V depending on if the blade is blocking or passing light
when it is stopped.
If measurement is either zero or +3V (or higher) the sensor is likely to be
defective.
PCB5 – If previous measurements do not indicate bad flow sensor, measure at on
pin 6 of the 34 ckt. ribbon cable, CN11 to J36. The output of PCB5 on the ribbon
cable is open collector with 4.7K pull-up in the CCM. Here the pulse is between
0-5V with normal flow being around 2-4V. Either zero or 5 V indicates PCB5 is
likely defective.
CCM – If previous measurements do not indicate sensor or PCB5 is bad then fault
in probably in the CCM. Other possibility, the 34 ckt ribbon cable could be open
or shorted.
4-5
Low Coolant Level Warning
If coolant level becomes low during a cut it does not shut off the system but
does flash code 4-5 as a warning. See sect. 4-1 for troubleshooting low coolant
codes.
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The 5 Group relates to CANBUS communication errors. The GCM 2000 & 2010
also have some codes to consider. These are listed following this Group 6.
5-1 CANBUS Failure to Acknowledge fault.
 Gas control is GCM 1000 with Basic ID problem
 CANBUS / Fiber optic problem
GCM 1000 (also called a Basic Gas Control) does not use the CANBUS (fiber
optic) communication. A jumper in the gas control connector J56 pins 8 & 9, gives
the signal “Basic ID” telling the CCM not to expect any CANBUS. If this circuit,
Gas Control cable, connector pins, connection from the rear panel GCM connector
J55 to the CCM (J5) is open CCM will expect CANBUS and report this error
because there isn’t one.
CANBUS / Fiber optic communication errors can be difficult to troubleshoot,
especially when they are intermittent. Things to look for are:
 the connectors not locked in place (CCM or GCM)
 The fiber is damages or bent sharply. Should not be the case if the fiber in
inside the protective hose and the hose properly secured in the strain relief but
that is not always the case.
 Dirt on the ends of the fiber or in the receiver/transmitter where the fiber plugs
in. Blow out gently with clean dry air such as is used to clean camera lens.
 Excessive electrical interference. While the fiber is immune to EMI it can
bother circuits at either end. Check than that All the grounding connections
and clean and tight. Check the resistance of the ground rod (with all wires
disconnected from it). It may have increased due to dryer weather conditions.
 Defective receiver/transmitter or other circuits on either CCM or Gas Control
main board. For the CCM you can plug the fiber into another
receiver/transmitter pair to see if that works. Otherwise replace either (or
both) Gas Control main board or CCM.
5-2 CANBUS off due to excessive errors.
See 5-1 code for troubleshooting CANBUS faults.
5-3 CANBUS Data Error Warning.
This is a warning, does not shut the system down but is an indication that it
probably will shut down soon (5-2 code). Troubleshooting is same as for 5-1.
5-4 CCM message not sent.
Troubleshooting same as for 5-1.
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Group 6 Codes
These were all supposed to
indicate CCM errors where you just replaced the CCM but we did find the coolant flow
upper limit of 2.7 gal/min can be exceeded if the coolant tube in the torch is missing or
broken off so it doesn’t restrict the flow.
Starting in May 06 with V2.4 code, we've added code group 6.
The codes are as follows:
"6-1" = CCM Analog Voltage Error
"6-2" = CCM Analog to Digital Converter (ADC) or Digital to Analog Converter
Error.
"6-3" = Coolant Flow Circuit Error (Flow rate too high)
"6-4" = CCM Data Memory Error.
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