QSK 60G & 60G High Efficiency Series
Gas Engines
Module 6 – ENGINE CONTROL SYSTEM
Cummins Corporate Training
1
HE -60G/ Control / BMG / 03 - 07 / REV 01.
Engine Control System
Learning Objective
Participants will be able to locate and identify base engine control
components and describe their operation within a total system.
Agenda
• Engine Control System - Capability & Integration.
• Control Component location and function:
- Control Module 700,
- Systems Module 558,
- Ignition Module,
- CENSE / Control Module 850.
• Ignition System.
• Engine Sensors and Speed Probes.
• System logic states.
2
Engine Control System Capability
ƒ Continuous Monitoring of:
– Lubrication System
– Cooling
– Air/Fuel handling
– By cylinder (detects in-cylinder problems)
– Others (operation hours/duty cycle, etc.)
– Over 1200 fault codes mapable!
ƒ Information Management for future analysis:
–Trend Data for Engine performance, durability, and maintenance intervals.
3
QSK Gas Engine Control System
Fully Integrated Controls: Fuel System-Ignition System-Governing-Genset
CUMMINS
SERVICE
TOOL
Sensor
Signal
CENSE /
CM850
J 1939
PDM
Bank 1
COP’S 1 - 8
Ref . Gnd .
8 Bit Bus
Ref
* PDM - Prognostic
Diagnostic Module
CCD - Capacitor
Coil Driver
MCM-700
Master
Fire
-320v
CCD
CAN 2.0B
Combustion
Combustion
Controller
Controller
SSM-558
CM - 5XY
Sensor
Signal
PDM
IGNITION MODULE
* Future development feature.
Control System Schematic
Ref . Gnd .
8 Bit Bus
-320v
Ref
4
Gnd.
Fire
CCD
Gnd.
Bank 2
COP’S 9 - 16
System Components – Standard QSK60G shown as example
IGNITION RELATED :CM 558, IGNITION
MODULE, COP.
COP
FUEL RELATED :CM 700, CM558.
MONITORING ONLY:CENSE or CM850
CENSE Module
or CM850 on High
Efficiency version.
CM
558
Ignition
Module
5
NOTE : QSK60G shown
CM 700 Mounted off engine in GIB.
( Generator Interface Box - GIB).
CM700
Network Data Links
Not fitted on Inline Gensets
Peer to Peer
(Multi-tasking)
Data Link
MODBUS
(1900 baud)
Slave
J1939
(250K baud)
SERVICE TOOL
CONNECTOR
Cummins
Proprietary
CAN 2.0B
(500K baud)
Master \ Slave
(Point to Point)
Data Link
Peer to Peer
(Multi-tasking)
Data Link
Master
CENSE on H/E
QSK 60G
CM700
CENSE on
standard
QSK 60G
CM558
CM558
k
or
w
et
N
CM558
Networks constructed
with twisted two core
shielded cable.
External terminating
resistors fitted where
indicated
120 Ohm - J1939 / CAN 2.0B
150 Ohm - MODBUS
CM558
e
on
kb
ac
B
e
on
kb
ac
B
(SHIELD)
k
or
w
et
N
(-)
N
A
C
9
93
J1
(+)
GENSET
PLC
CM700
CONNECTION CHECKS
Polarity - Terminating Resistors - Shield Connections
Quantum - Gas Engine Control Components
Note: H/E = High Efficiency Version
CM
700
MODBUS link
(19,200 baud)
CM
558
Fire
Sync
J 1939 Network
(250K baud)
Ignition
Module
To Coil-on-Plugs
2, 3, 4, 5….. etc.
Left Bank.
COP
Std 1 x
CENSE
‘V’ Engines
MODBUS
Link to
Genset
PLC
CAN 2.0 B Network
(500 K baud)
7
H/E 60 x2
CM850
COP
CM
558
Fire
Sync
Ignition
Module
To Coil-on-Plugs
2, 3, 4, 5….. etc.
Right Bank.
Master Control Module
CM700 - Master Control
Module:
• Solid state fully encapsulated,
one module required per
system.
• Located in Genset Interface
Box (GIB) (door mounted).
• Recognised by it’s 3 x 50 pin
Deutsch connectors.
• Non serviceable.
8
GIB - Genset Mounted
Just one of the terminal boxes added as
part of the Genset build.
Generator Interface Box (GIB)
Stay-in-Boot Switch and
O2 Sensor Power Adapter
Connector Socket Assembly
NOTE: Preliminary Panel Layout
HT & LT Engine
Temperature Controllers Neutral Bar
37A DC PSU
AC MCB’s
KM (DC) Relays
Solid-State
Relays (Engine
Temperature
Control)
CM700
Earth Bar
Harting
Connector
(GIB to GCP)
KM Contactor’s
Fuse Rail
9
AC & DC Engine
Connections
Under Voltage J1939 Service Interlocked AC
Isolator
Relay
Socket
Generator Interface Box ( Continued )
• Houses the ‘Stay in Boot plug &
socket’. ( Only used in special
program functions).
•Houses shutdown and isolation
relays.
• The CM700
• Has the Generator to Genset
Control Panel interconnection
Terminals.
NOTE: KW Signal for the torque
over boost closed loop control is
supplied from Power Command
Just one of the terminal boxes added as part
Supervisor (PCS). A separate KW
of the Genset build.
transducer is no longer required or
fitted
Note: Service tool connector is located in the free standing genset control panel.
10
•
CM 700 Function
Vee engine Control systems
HT Coolant
Temperature
HT coolant
Pressure
LT Coolant
Temperature
Turbo Speed Sensor
(2.0Mw H/E QSV &
QSK60G H/E only )
Lube Oil
Temperature
LT coolant
Pressure
Compressor Inlet Air
Temperature (60 only )
Crankcase Blow-by
( When fitted )
Lube Oil
Pressure
Crankshaft
Speed
Note: H/E = High Efficiency Version
MODBUS to Gen. PLC
Speed Bias Signal
Shutdown Signal
Engine Man. Switch
Genset Load (KWL)
Idle / Rated switch (PLC)
Stop / Start Switch (PLC)
Utility Breaker Status (PLC)
FROM
PCS
CM 700
Speed
Governing
+
Base Engine
Protections
Safety wire loop / Power
down Relay
Ign.
Engine
Exh.
Thermocouples
Start Solenoid
Fuel Shut off Valve
CM
558
CENSE
CM
558
Ign.
Standard arrangement shown
• Output Torque command (throttle driver signal) to CM558 Modules via CAN 2.0B data Link.
• Exhaust Temp info sent to CM700 from Cense via J1939 data link, except on H/E Engines.
• Total system data sent to genset Programmable Logic Controller via RS 485 data link.
Fuel & Ignition Modules
Ignition Module ( CCD) :
ƒ Solid state fully encapsulated, controls up to 9
cylinders
ƒ Non-serviceable.
ƒ Two Amphenol connectors;
one 19 pin - input from SM558,
one 17
pin - outputs to COPs.
CM558 - Sub Systems Module:
ƒ Solid state fully encapsulated, controls up to 9
cylinders.
ƒ Non-serviceable.
ƒ Two Deutsch 50 pin connectors, one input from
CM 700 one outputs to CCD.
12
Modules Mounted on Left and
Right Bank side of Engine.
Vee engine system with single fuel control
valve and single throttle (QSK Engines )
CM558 Function
Boost
Pressure
Intake
Man.Temp
& Pressure
Fuel Inlet &
Outlet
Pressures.Fuel
outlet Temp.
Engine
Speed &
Position
Gas Mass
Flow
Knock
.
Exhaust
O2 & Back
Pressure
LEFT BANK SENSORS
CM
700
CM 558
(Left Bank)
Ign.
Engine
To Generator
Control Panel
(PLC)
Throttle (Driver Signal)
Throttle (actuator Position Feedback)
Fuel Control Valve (Driver Signal)
Fuel Control Valve (Position Feedback)
Ignition Module (Sync / Fire Signals)
Safety Wire Loop / Power Down Relay
Compressor By-Pass Driver (H/E Only)
Comp By-Pass Driver Feedback (H/E Only)
LEFT BANK COMPONENTS
CM 558
CENSE
(Right Bank)
Standard arrangement shown
Ign.
Ignition Module (Sync / Fire Signals)
RIGHT BANK COMPONENTS
RIGHT BANK SENSORS
Engine
Speed &
Position
Knock
.
Note: H/E = High Efficiency Version
Duty Cycle Valve (FloTech)
• Part of the gas control assembly.
• Operates on the mark space ratio (duty cycle) of a 5v square wave signal from
CM558.
• Controls the gas supply to the mixer.
• This electronic butterfly valve effectively controls the air / fuel ratio (mixture) for any
given volume of fuel drawn through the gas control assembly as directed by the
CM558.
14
Open / Closed Loop Control
Air / Fuel ratio control on the engine in 3 basic modes:
1. Open-Loop.
2. Closed-Loop (with torque over boost feedback).
NOTE : Engines will be shipped in Open-Loop mode.
Open loop:
Has advantage of simpler
set-up, calibration and
trouble-shooting.
Closed loop:
Will ensure emissions do
not drift outside spec.
Air / Fuel ratio control mode:
The automated calibration in the service tool (INSITE) defaults the table in the ABank CM558 to to perform open-loop air / fuel ratio control. This default cannot be
changed.
Closed loop operation is switched on/off via service tool
15
Ignition System
• DC to DC converter steps up the
supply voltage to approx 300 v,
which charges the capacitor.
• Signal from CM 558 closes an
electronic switch in the ignition
module, the capacitor charge
discharges into the primary
windings of the Coil on plug
( COP).
• The voltage induced into the
secondary winding of the COP is
supplied directly to the spark plug
and rises (up to 40Kv) until it
overcomes the resistance of the
electrode to ground strap air gap.
• The PDM is being developed as
a future diagnostics tool.
16
Ignition Module
DC TO DC
CONVERTER CAPACITOR
+
P
D
M
PRIMARY &
SECONDARY
WINDINGS
COP
24V
CM558
PLUG
CCD Output Harness
The Ignition Module output pins for firing sequence are fixed as shown in the
table below.The harness connections therefore determine the cylinder firing
order!
Pin
Type
A
B
C
D
E
F
R
P
G
J
K
L
-Vdc 1
-Vdc 2
-Vdc 3
-Vdc 4
-Vdc 5
-Vdc 6
-Vdc 7
-Vdc 8
IGN-COP
HVS-S
HVS-GND
HVS-SIG
CCD/PDM - 17 Pin Output Connector
Comments
Ignition Coil Power
* Dependant on firing order V12/16.
Ignition Coil Power
Ignition Coil Power
Ignition Coil Power
Ignition Coil Power
Ignition Coil Power
Ignition Coil Power
Ignition Coil Power
Ignition Coil Ground
High Voltage Sensor shield. Connected to CCD-CDM case
High Voltage Sensor Ground ref. Connected to GND at COP
High Voltage Sensor Input Signal
WARNING: Incorrect fitting can cause exhaust explosion.
17
To
*COP#1
*COP#2
*COP#3
*COP#4
*COP#5
*COP#6
*COP#7
*COP#8
COP
None
COP
COP
Drive wheel for Camshaft position sensor pick-up QSK engines
+1 pulse
Drive wheel fitted to Left bank camshaft
only. Dual output Sensor connected to
Left & Right bank CM558.
QSK 60
24+1 pattern
+ 1 pulse used to trigger ‘Ref’ signal for start of ignition cycle.
Example of CM558 ‘Fire’ signal to Ignition module with Timing retard on cylinder 3.
Cyl. Firing.
+1 pulse
‘REF’
reset
received
°
±
ž
Ÿ
‘FIRE’
Ignition module will ‘Fire’
the spark plug on falling
edge of signal.
Ignition
Module
‘REF’
The ‘Ref’ signal resets the Ignition Module counter that switches output to the Cylinder
1,2,3 etc. back to No 1 each time the camshaft position sensor reads the +1 pulse.
Cyl. 1
Cyl. 2
Cyl. 3
Cyl. 4
Cyl .5
Cyl. 6
Cyl. 7
Cyl .8
Cyl. 9
Position Sensor & Speed Probes
New pictures Required
Engine Position Sensor
One off Left - bank camshaft
Dual Output Speed Probe:
1 to MCM700, 1 not used.
Dual Output Speed Probe:
CM558’s (output to Left & Right bank
units).
Speed probe Part No. 3865350
When installing check probes are over one of the teeth, set clearance to 0.8mm
(back-off 3flats).
19
Engine Sensors
IMPORTANT: Torque to 20Nm +/-2
Heated Oxygen Sensor :
Knock Sensor:
1-off, fitted in left bank exhaust
elbow OUTPUT: 0 - 5vdc.(Also
requires 12v dc heater supply)
ONLY FOR ERVICE USE.
One per cylinder, fitted to head,
pizzo electric crystal.
Back Pressure Sensor : 1-off, fitted
in left bank exhaust elbow
20
NOM OUTPUT: 1v dc.
> 2.1 v IGN retarded 3º (twice then
shutdown)
> 4.5 v Immediate Engine Shutdown
Engine Sensors
Gas Mass Flow Sensor:
• Located in the Gas Control assembly.
• Operates on a 12v dc “hot wire” system, the
output is up to 7.8v although the CM558 can
only read up to 5.0v.
• The gas control assembly is located towards
the front end of the engine.
• The information is then fed to the CSM 558
module which adjusts the duty cycle to give
the correct gas flow as defined in the 558
control map.
Ambient Temperature Sensor :
• Compressor inlet temperature sensor is
mounted in the left bank air filter housing to
monitor ambient air temperature.
21
Engine Sensors
P1
FUEL
FLOW
• P1 - Boost Pressure (before
throttle actuator).
• P2 - Intake Manifold Pressure
(after throttle actuator).
• T1 - Intake Manifold Temperature
(after throttle actuator).
THROTTLE ACTUATOR
LEFT BANK MANIFOLD
NOTE:
All sensors feed Left bank CM558 for
mixture control.
Right bank CM558 has ignition only.
22
P2
T1
ProAct Driver & Actuator
The ProAct III Actuator driver is
mounted on the Genset The throttle
actuator operates on a closed loop
feedback system with the driver module
in order to determine actuator position.
This information is then fed back to the
CM558 for display and trouble shooting.
The ProAct III actuators are designed for larger gas and diesel engines not requiring governing backup systems. The primary features of the system are:
– An all electric 75 degree rotary actuator, engine-mountable.
– An adjustable driver with 4-20 or 0-200mA Control for connecting with many
governor & control systems.
– Extremely fast & accurate.
23
CENSE Module / CM850 Modules
On the QSK60G, the CENSE module is
located at the rear of the right bank intake
manifold as shown.
Its primary function is monitoring of the
exhaust pyrometers mounted in each
cylinder head exhaust passage.
CENSE MODULE or CM850
LOCATION.
Exhaust
Pyrometer
24
NOTE: The CENSE module is
replaced by two CM850
modules, one mounted on each
bank on the QSK60G H/E. The
function of the CM850 is the
same as CENSE.
CENSE Function – QSK60 G ONLY
To Generator
Control Panel
(PLC)
Service
Connector
RS 232
Exhaust Port Temperatures (Left Bank)
CM
700
CM
558
Ign.
J1939 Service
Connector
Engine
TH1
TH2
TH3
TH4
TH5
TH6
TH7
TH8
J1939
CM
558
CENSE MODULE
TH9
TH10
TH11
TH12
TH13
TH14
CAN 2.0B
TH15
TH16
Ign.
CENSE – Download via 9 pin
D connector (RS232) in GIB
or via INSITE and Engine
Service Tool point.
Exhaust Port Temperatures (Right Bank)
• Thermocouples signals are connected to CENSE module K - Type inputs. The
Cense module has 16 K-Type Inputs.
25
CM 850 Function – QSK60 G/HE ONLY
J1939 CM 850 Service Connector
(For INSITE Download ONLY).
Monitor via HMI or System J1939
Service Connector and INSITE)
To Generator
Control Panel
(PLC)
CM
700
CM
558
Exhaust Port Temperatures (Left Bank)
(Address 27)
J1939 System
Service Connector
THA1
THA7
THA2
THA3
THA4
THA5
THA6
Ign.
(Address 00)
Engine
THA8
J1939
CM 850 MODULE – LEFT BANK (Address 0xF1)
CAN 2.0B
CM
558
Ign.
(Address 01)
CM 850 MODULE – RIGHT BANK (Address 0xF2)
THB9 THB10 THB11 THB12 THB13 THB14 THB15 THB16
CM850 – Download using INSITE
connected via J1939 and 9 pin ‘D”
connector in GIB ONLY.
Exhaust Port Temperatures (Right Bank)
• CM850 modules have no K-Type Inputs. Thermocouples with combined K - Type signal converters are
connected to the CM850 modules. One module is mounted on each bank. The CM850’s are connected by, and
communicate with, the CM700 via the CAN 2.0B network.
• INSITE will auto detect module address. Engineering J1939 Service tools require module address input.
26
QSK60G HE – EG THERMOCOUPLES
•
CM850 modules have no K-Type inputs.
Therefore Thermocouples with combined
K - Type signal converters are connected
to the CM850 modules.
•
•
Thermocouple Pt.No. 495448.
•
Temperature Vs sensor output is shown in
the table. The lower the output the higher
the temperature.
•
Thermocouple
The signal converter is built into the 3-pin
harness plug.
Pin Layout
Harness pin-out is :
Pin 1 –Sensor Supply from ECM.
5.0 v dc.
1
2
Pin 2 - Sensor ground.
0 v.
Pin 3 – Sensor output voltage
0.2 to 4.2 v dc.
Pin 4 – not fitted / used.
27
3
4
Temp ( C)
V (out)
0
4.2
50
3.95
100
3.7
150
3.45
200
3.2
250
2.95
300
2.7
350
2.45
400
2.2
450
1.95
500
1.7
550
1.45
600
1.2
650
0.95
700
0.7
750
0.45
800
0.2
FSO
Vent
Fuel Shut Off
Valves 1&2
1
Ignition
Module
L.Bank
2
Ignition
Module
R.Bank
Throttle
Driver.
+ 24v
Fuel
Control
Valve
E stop
Pushbutton
Circuit.
Ground
CM558
FSO/Vent
Relay.
V
CM700
FSO/Vent
Relay.
Engine
E -Shutdown
indication to
genset
controls
PLC
E-Stop
PCS
E-Stop
Battery
Conservation
Relay.
+ 24v
+ 24v
E-Stop
Pushbutton
Relay.
C26 B27
Shutdown Request
E-Stop Input
Isolated Battery (+24v)
CM700
Isolated Battery (+24v)
B39 A49 A50 C27
Switch Return
+ 24v
Battery Conservation
CM558B
B48
Safety Wire
A43
FSO Control
Isolated Battery (+24v)
CM558A
A49 A50
Isolated Battery (+24v)
Fuel Shut Off -
Fuel Shut Off +
Isolated Battery (+24v)
A49 A50 A43 A44
Isolated Battery (+24v)
CM700
Ignition
Power
down
Relay.
CAN Datalink
+ 24v
+ 24v
Genset
Controls
E-Stop
Relay.
Normal
Shutdown
Request
from
Engine
Controls
to Genset
Controls
Shutdown & Isolation
CM 700 System State Control
STOP
Stop/start switch = start
and MXSRCNEN = 0
and ENGRPM = 0
Stop/start switch = stop
and ENGRPM = 0 and
authorized N_SHUTD
condition is not active
Authorized N_SHUTD
condition occurred
Keyswitch off and
ENGRPM = 0 then
keyswitch on OR
power cycle
Authorized E_SHUTD
condition occurred
Authorized
N_SHUTD
condition
active
Authorized
E_SHUTD
condition
occurred
N SHUTD
Stop/start switch transition
from stop to start and
MMVENTSS = MUSTVENT
and MXSRCNEN = 1 and
MMSTOKFG = 1
Start cycle finished OR
Authorized N_SHUTD
condition occurred and
MXSRCNEN = 1
Authorized
E_SHUTD
condition
occurred
E SHUTD
VENT
START
Vent cycle finished
Authorized N_SHUTD
condition occurred
Authorized E_SHUTD
condition occurred
Authorized N_SHUTD
condition occurred and
MXSRCNEN = 0
Authorized E_SHUTD
condition occurred
Authorized N_SHUTD
condition occurred
29
ENGRPM > MMMNRNES
RUN
Stop/start switch transition
from stop to start and
MMVENTSS = VENTED
and MXSRCNEN = 1 and
MMSTOKFG = 1
OR
Stop/start switch = start and
MXSRCNEN = 0 and
MMSTOKFG = 1 and
ENGRPM > 0
Engine State Control Drivers
State
CM700
Controlled
Starter
Safety Wire
Driver
CM558 Controlled
Fuel Shut
Off Valve
Spark
STOP
VENT
START
off
on
on
on
on
on
on
on
on
closed
closed
open
off
off
on
RUN
off
on
on
open
on
N_SHUTD
off
on
on
closed
on, for
SHSKIHTM
after entering
N_SHUTD
state
E_SHUTD
off
off
off
closed
off
Throttle
Position
C_SPTHPS
C_VTTHPS
Fuel
Control
Valve
Position
C_SPDC
C_VTDC
between
C_THMNSR
and
C_THMXSR
between
C_THMNRN
and
C_THMXRN
between
C_THMNRN
and
C_THMXRN
between
C_AFDCLL
and
C_AFDCLU
between
C_AFDCLL
and
C_AFDCLU
between
C_AFDCLL
and
C_AFDCLU
closed
closed
Table of Essential Control Drivers Which are Tied to Engine State
30
Electronic Temperature Controllers
Eurotherm – Model 3216 – refer to handout ( H/E models only)
Note: Two controllers are used :
• 1 for ‘HT’ 3 way Valve control, 1 for ‘LT’ 3 way Valve control.
• Output 1 drives 3 way Valve OPEN – flow out to cooler.
• Output 2 drives 3 way Valve CLOSED – flow back into engine.
• Ambient operating temperature range of controller - 0 and 55 oC (32 - 130oF).
31
Electronic Temperature Controllers
Auto/Manual Operation
Auto is the normal closed loop temperature control mode, which means that the output
power is adjusted automatically by the controller in response to the measurement from
the input sensor.
In Manual mode the controller can be set so that the output power can be adjusted
directly by the operator. This may be useful during commissioning or if the sensor
becomes faulty and it is required to continue temporary operation of the plant until the
sensor is repaired or replaced.
Manual operation must be used with care and the power level set must be chosen
such that no damage can occur to the 3 way valves.
To Select Auto/Manual and Adjust the Output Power.
•
•
Press RAISE and LOWER (Mode) together.
This can only be accessed from the HOME
display.
Refer to EUROTHERM handout
32
Electronic Temperature Controllers
FIVE ACCESS LEVELS
Operator level 1 is designed for day to day operation of the controller and is not protected
by a security code. Level 2 and above provide access to additional parameters and
access is protected by a security code. Level 3 makes ALL operating parameters
available. Configuration Level makes all operational & Configuration parameters available
for changing the fundamental characteristics of the instrument to match the process
eg. Input (thermocouple type); Alarm type; communications type.(Level 3 / Config factory
set - not normally used).
To Enter Level 2
From any display press and hold ‘PAGE’.
After a few seconds the display will show ‘Lev 1 G ot o’. Release .
(If no button is pressed for about 20 seconds the display returns
to the HOME display)
Press ‘RAISE’/’LOWER’ to choose Lev 2 (Level 2).
Press or to enter the correct code, By default this is set to ‘2’
If an incorrect code is entered display reverts to the HOME display
To Return to Level 1
Press and hold 'PAGE’
Press ‘LOWER’ to select LEV 1
It is not necessary to enter a code when going from a higher level to a lower level.
When Level 1 is selected the display reverts to the HOME display
33
Electronic Temperature Controllers
HOME – Level 1 “Auto” view shown - lower display scrolls a ‘help’ message which gives
the name of the parameter being displayed, e.g. ‘w orkin g setp oin t’
In Operator Level 1 - you can:
• Acknowledge alarms
(when the alarm option is fitted).
• Adjust temperature set point,
•Select auto or manual operation.
NOTE: All input ranges of the controller have been calibrated against traceable
reference standards by the manufacturer. This means that if the input type, or
sensor, is changed it is not necessary to calibrate the controller (PV offset).
34
Electronic Temperature Controllers
To Return to the HOME Display :
Press ‘PAGE’ + ‘SCROLL’ together.
On release of the keys the display
returns to the HOME list. The current
operating level remains unchanged.
To Set the Required Temperature :
Press ‘RAISE’ to raise the set point,
or ‘LOWER’ to lower the set point when the HOME display is being
shown.
The new set point is entered when
the button is released and is
indicated by a brief flash of the
display.
35
Electronic Temperature Controllers
DEFAULT FACTORY SETTING FOR :
QSK 60 H/E
QSV91 (18 bar)
Timer not configured
Timer not configured
HT – WKG. SET POINT 1 (°C /°F )
HT – SET POINT HIGH (°C /°F )
HT – SET POINT LOW (°C /°F )
LT – WKG. SET POINT 1 (°C /°F)
LT – SET POINT HIGH (°C /°F )
LT – SET POINT LOW (°C /°F )
WKG. OUTPUT (% range limit)
( – 100% max cooling to + 100% max heating)
SET POINT RATE LIMIT (SP.RAT)
(SP.RAT = rate of change heat / cool)
TIMER STATUS (T.STAT)
FACTORY DEFAULT SETTINGS - Will require tuning & adjustment to suit site equipment
and conditions. Adjustments made during commissioning.
36
Electronic Temperature Controllers
37
Temperature Controllers – Wiring
Model 3216 – refer to handout
Alarm output – Option (Not fitted)
Temp sensor – mA input used.
Communications output – Not used
24v dc supply used
38
Temperature Controllers – Wiring
+ 24v dc.
From CM700 – HT
sensed temperature (mA).
HT
3-way valve.
- 24v dc.
From CM700 – LT
sensed temperature (mA).
LT
3-way valve.
39
Controller Action - Temperature
controllers read sensed temperature
from CM700 and drive the 24v dc 3-way
valves to match Temperature controller
set point.
QSK 60G & 60G High Efficiency Series
Gas Engines
Module 6 – CONTROL SYSTEM
End
Cummins Corporate Training
40
HE -60G/ Control / BMG / 03 - 07 / REV 01.