VLS-VLH control
4 Compressors
ELECTRONIC
SERVICE MANUAL
VLS/VLH 09/05
VLS-VLH CHILLER - 4 COMPRESSORS
1
GENERAL INFORMATION
2.1
1.1
INTRODUCTION
2.1.1 GENERAL INFORMATION
This document contains the information and the operating instructions for VLS-VLH 4 compressors & electronic
control.
This information is for the after-sales service and the production operators, for the end-of-line testing.
1.2
The figure shows the terminal with the front door open.
It is provided with a LCD 4 lines x 20 columns, keyboard and microprocessor-controlled LED's, so as to
allow the programming of the control parameters (setpoint, differential bands, alarm thresholds) and the main
operations to be carried out by the user.
MAIN CHARACTERISTICS
– Microprocessor control
– User-friendly keyboard
– Proportional and integral control of the return water
temperature (RWT)
– Hysteresis control of the leaving water temperature
(LWT)
– Access code to enter the Manufacturer's Level
– Access code to enter the Assistance Level
– Alarm buzzer and LED
– backlighted LCD
– Closed-loop condensing pressure control
– Pump-Down logic (start-stop)
– Rotation of the compressor operation
– Oil return function
– Night mode (or Low Noise) control
– Counting of the pump/compressors' hours of operation
– Display of discharge pressure values
– History of stored alarms (option)
– Programming of different setpoints with 4 ranges of
time/setpoint.
The following accessories can be also connected:
– Real Time Clock Memory Card: alarm history and programming of different setpoints with ranges of time
– Serial Communication RS485 Card; to connect the
Chiller Control to a BMS network
– Remote Display Terminal
– Wire Remote Control
– Phase monitor kit
2
KEYBOARD & DISPLAY TERMINAL
2.1.2 TERMINAL & KEY BOARD DESCRIPTION
The terminal makes it possible to carry out the following
operations:
– the initial configuration of the machine
– the change of all the main operating parameters
– the display of the detected alarms and their acoustic
signalling by a “buzzer”
– the display of all the measured quantities
The terminal and the card are connected by a 6-way
phone cable.
The connection of the terminal to the basic card is not
essential for the normal operation of the controller.
CONTROL OF VLS-VLH
WITH 4 COMPRESSORS
THE CHILLER CONTROL SYSTEM
The VLS-VLH machines with 4 scroll compressors are
provided with a microprocessor card which is fully programmed by default for the control of a chiller of cold
only type with 2 circuits, 2 compressors per circuit, a
high-pressure transducer per circuit. The control system
consists of:
2
VLS/VLH 09/05
Access to the “display mask” of the machine
status.
4. Arrow down key: allows you to set the control parameters' values and to move from one mask to another
(not backlighted).
5. Enter key: used to move the cursor inside the masks
and to save the values of the set parameters. This key
is always backlighted (yellow light) to indicate the
presence of the power supply.
Access to the “maintenance level mask”.
Access to the “printing mask” (not available).
2.2
DISPLAY
Access to the “display mask” of the status of
digital/analog inputs and outputs.
Access to the “clock“ mask” (if the clock card is
available).
Access to the display/control “setpoint masks”.
Access to the “Service Level” masks.
The display is an LCD 4 lines x 20 columns. The quantities and the information about the operation of the unit
are alternated in the form of subsequent screens, named
"masks".
Press these keys at the same time to
enter the "manufactur-er Level masks “of
the machine.
You can move inside the masks with the terminal keys,
as described below.
+--------------------+
x
Line0
Home
Line1
Line2
Line3
+--------------------+
Displays the information on the software version.
The LED's next to each key light up when the relative
function is enabled.
2.3
KEYBOARD
2.3.1 ARROWS KEYS - UP/DOWN/ENTER
1. On/off key: allows you to turn the unit on/off. The
green LED which lights up the key indicate the status
of the unit.
If the cursor is in the top left-hand corner (Home), press
the UP/DOWN keys to access the subsequent masks
associated to the selected branch. If a mask includes
some value setting fields and you press the ENTER key,
the cursor will reach these fields.
2. Alarm key: used to display the alarms, to reset them
in manual mode and to silence the buzzer. If the key
lights up (in red), at least an alarm has been identified.
Press it one to silence the buzzer and to display the
mask of the activated alarm.
Press it again to reset the alarm signal.
Once you have reached the quantity setting field, you
can modify any value (within the expected limits) by
pressing the UP/DOWN keys.
After you have selected the desired value, press the
ENTER key again to store it.
3. Arrow up key: allows you to set the control parameters' values and to move from one mask to another
(not backlighted).
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VLS/VLH 09/05
2.3.2 ALARMS
Code
Alarm description
Comp
Status
Ventil.
Status
Pump
Status
Aut/Man
Reset
Delay
AL01
AL02
AL03
AL04
AL05
AL06
AL07
AL08
AL11
AL12
AL13
AL14
AL15
AL21
AL22
AL23
AL24
AL25
AL26
AL27
Off
Off Sys 1
Off Sys 2
Off
Off Sys 1
Off Sys 2
Off Sys 1
Off Sys 2
Off Comp. 1
Off Comp. 2
Off Comp. 3
Off Comp. 4
Off
Off
Off
Off
Run
Run
Run
Run
Off
Off
Off
Off
Run
Run
Run
Run
Run
Run
Run
Run
Off
Off
Off
Off
Max
Run
Run
Max
Off
Run
Run
Off
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Run
Man
Man
Man
Man
Man
Man
Man
Man
Man
Man
Man
Man
Man
Auto
Auto
Auto
Auto
Auto
Auto
Auto
30 sec
No
No
Parameter
Parameter
Parameter
No
No
No
No
No
No
No
10 sec
10 sec
10 sec
10 sec
10 sec
10 sec
10 sec
Run
Max
Run
Auto
10 sec
AL31
AL32
AL33
AL34
AL35
AL55
Efficiency alarm CPS
Sys 1 Antifreeze alarm
Sys 2 Antifreeze alarm
Flow meter alarm
Sys 1 Low pressure
Sys 2 Low pressure
Sys 1 High pressure
Sys 2 High pressure
Thermal switch, compressor 1
Thermal switch, compressor 2
Thermal switch, compressor 3
Thermal switch, compressor 4
Thermal switch, fans
Failure of sensor B1 Tin
Failure of sensor B2 Tout1
Failure of sensor B3 Tout2
Failure of sensor B4 Tair
Failure of sensor B5 Tcoil1
Failure of sensor B6 Tcoil2
Failure of sensor B7 Sys 1 HP
pressure transducer
Failure of sensor B8 Sys 2 HP
pressure transducer
Maintenance of compressor 1
Maintenance of compressor 2
Maintenance of compressor 3
Maintenance of compressor 4
Pump maintenance alarm
Failure of clock card
Run
Run
Run
Run
Off
Run
Run
Run
Run
Run
Off
Run
Run
Run
Run
Run
Off
Run
Man
Man
Man
Man
Man
Man
AL56
Thermal switch, compressor 1
Off Comp. 1
Run
Run
Man
AL57
Thermal switch, compressor 2
Off Comp. 2
Run
Run
Man
AL58
Thermal switch, compressor 3
Off Comp. 3
Run
Run
Man
AL59
Thermal switch, compressor 4
Off Comp. 4
Run
Run
Man
AL60
AL61
AL62
AL63
Sys 1 Low pressure
Sys 2 Low pressure
Thermal switch, fans
Sys 1-2 Antifreeze alarm
Off Sys 1
Off Sys 2
Off
Off Sys 1-2
Run
Run
Off
Off
Run
Run
Run
Run
Man
Man
Man
Man
No
No
No
No
No
No
1 time auto VLS
3 time auto VLH
1 time auto VLS
3 time auto VLH
1 time auto VLS
3 time auto VLH
1 time auto VLS
3 time auto VLH
3 time auto
3 time auto
1 time auto
1 time auto
AL28
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VLS/VLH 09/05
Notes
defrost every 40’
defrost every 40’
2.3.3 MENU KEY
Press the “menu” key to display the main mask:
RWT................................. °C
SYS 1 comp off
SYS 2 comp off
Unit off
2.3.4 MAINTENANCE LEVEL KEY
Press the “Maintenance” key to access the following masks :
Parameter
Type
Min. Value
Max. Value
Default
3
0
N° 0000
AL 000
h 00:00
00/00/00
Setpoint
00,0 °C
Water temp.
00,0 ° C
Pump
000000 h
SYS 1 – comp. 1 .
000000 h
SYS 1 – comp. 2 .
000000 h
SYS 1 – comp. 3 .
000000 h
SYS 1 – comp. 4 .
000000 h
Insert the password
0000
1234
Offset probe
T in
°C
-3
T out
°C
-3
3
0
T air
°C
-3
3
0
T coil 1
°C
-3
3
0
T coil 2
°C
-3
3
0
DP 1
bar
-3
3
0
DP 2
bar
-3
3
0
N(Hours x1000)
0
100
10
Pump
flag
N=NO
Y=YES
N
Compressors
flag
N=NO
Y=YES
N
Maintenance
Alarm thershold
Reset hours
Disabile compressors
C1: N
2.3.5 PRINTING KEY
C2 : N
C3 : N
C4 : N
(Not used)
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VLS/VLH 09/05
2.3.6 I/O (INPUT/OUTPUT) KEY
Press the I/O key to access the display masks of the val-ues of all sensors mounted on the machine:
Acronym
Description
Tin
Entering water temperature
Tmixed
Leaving water temperature
Tair
Room air temperature
Tcoil1
Coil 1 sensor defrost control
Tcoil 2t
Coil 2 sensor defrost control
DP-1
Sys 1: discharge pressure transducer
DP-2
Sys 2: discharge pressure transducer
IN
Status of the Chiller Control's digital inputs
OUT
Status of the Chiller Control's digital i outputs
Chiller control
Code ………..
Rel. ……….
2.3.7 CLOCK KEY
Press the “clock “ key you can access the following masks:
User parameters
Control mode
Min. Value
Max. Value
00:00
24:00
Default
Clock
Hour
Day
Monday
Sunday
Date
01.01.05
12.12.05
Daily
Time zone with variation of the setpoint
N=NO
Y=YES
If Daily zone Y you can to enter
in the follow mask
Setp1= 00.0
-
00:00h
Setp2= 00.0
-
00:00h
Setp3= 00.0
-
00:00h
Setp4= 00.0
-
23:59h
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VLS/VLH 09/05
N
2.3.8 USER LEVEL - SETPOINT KEY
are listed below, together with the limit values and the
default values (standard shop set-up).
Press the Set key to enter the Setpoint level, which can
be accessed by the user. The parameters that can be set
User parameters
Control mode
Min. Value
Max. Value
Default
Sys #1 ON/OFF
–
OFF
ON
OFF
Sys #2 ON/OFF
–
OFF
ON
OFF
Cooling Setpoint
Return
mCS+2
20
10
Outlet
mCS
20
8
Heating Setpoint
Return
20
MHS-5
40
Outlet
20
MHS
40
Glycole Setpoint
Return
–15
20
10
Outlet
–15
20
8
Proportional Band
Return
1
10
5
Neutral Band
Outlet
1
6
2
Language selection
—
ITA
ENG
GER
SPA
FRA
ITA
At this level you can select the language of opera-tion
(English or Italian). French, German and Spanish are
available with other eproms.
Where mCS = min. cold limit for the setpoint (see
Service level)
Where MHS = max. heat limit for the setpoint (see
Service level)
When the machine is turned on, every single circuit is
activated through the SYSTEM # ON/OFF parameters
(SET key).
2.3.9 SERVICE LEVEL KEY
Press the “Prog” key (correct password 1234) to access the Service Level:
Parameters
Type
Min. Value
Max. Value
Default
Min. time stop compressor
Sec
10
600
90
Min.running time compressor
Sec
10
180
90
Time betw. On same compr.
Sec
10
999
450
Loading time Between comp.
Sec
10
999
20
LWT
Unloading time compressor
Sec
10
999
20
ChillerNet
Flag
N=NO
Y=YES
N
Water temperature control mode
Flag
RWT - P
RWT P+I
LWT
RWT P
RWT P+I
Sec
0
999
600
°C
-20
+20
4,5
R134A
unit
LWT Stop Comp
Cooling
Heating
Heat set. comp.
°C
+20
+60
55
Flag
N=NO
Y=YES
N
Set point
°C
-999,9
999,9
005.0
Diff.
°C
-999,9
999,9
10.0
Max.
°C
-999,9
999,9
005.0
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VLS/VLH 09/05
Parameters
Type
Min. Value
Max. Value
Default
Cool set.comp.
Flag
N=NO
Y=YES
N
Set point
°C
-999,9
999,9
24.0
Diff.
°C
-999,9
999,9
10.0
Max.
°C
-999,9
999,9
-002.0
Auto restart
Flag
N=NO
Y=YES
N
Glycole
Flag
N=NO
Y=YES
N
Enable rotation
Flag
N=NO
Y=YES
YES
Clock 32 Kbyte
Flag
N=NO
Y=YES
N
Remote logic
Flag
N=NO
Y=YES
N
Stand-by
hour
1
24
12h
Delay stop
Sec
0
60
20
running
Sec
0
99
1
Start-up
Sec
0
99
10
Sec
0
99
40
Limit
°C
-15
10
4
Diff.
°C
0
99
2
Setpoint
°C
-15
10
5
Diff.
°C
0
99
2
Condensation
type control
(note 2)
Flag
STEP
FSC
STD: STEP
LAK: FSC
Delay start fans
Sec
-10
10
0
°C
-20
0
-10
Setpoint (with odd fans)
°C
-20
0
-20
Diff.
°C
0
99
45
HP1
bar
16
28
21
R134A
unit
Pump management
Flowswitch/Interbloc delay time alarm
Low pressure
Delay time
Antifreeze
Antifreeze heater
LS (low speed) only if STEP
Setpoint (with peer fans)
LS (low speed) only if STEP
LP1
14
bar
10
16
13
7
DPSET (only if FSC)
bar
10
24
15
10
MINDP (only if FSC)
bar
1
25
10,5
6
MIN Speed (only if FSC)
Vdc
0
10
0
MAX Speed (only if FSC)
Vdc
0
10
10
MDP
bar
18
28
24
15
High
bar
18
28
26
18
Condensation
Fan step heating
with odd fans Low
°C
0
99
15
with peer fans Low
°C
0
99
20
High
°C
0
99
30
8
VLS/VLH 09/05
Parameters
Type
Min. Value
Max. Value
R134A
unit
Default
Defrost mangement
Start
°C
-20
20
0
Stop
°C
-20
20
8
Start time
Min
0
99
40
Max time
Min
1
10
5
Off tandem
Sec
N=NO
Y=YES
N
Enable
Flag
N=NO
Y=YES
Y (VLS)
N (VLH)
Max time
Pump down
Sec
5
90
10
Min.cooling
setpoint (mCS)
°C
5
12
6
Max. heating
setpoint (MHS)
°C
30
55
45
Efficiency
value
bar
0.0
3.0
0
Flag
N=NO
Y=YES
N
enabled
Flag
N=NO
Y=YES
N
enabled
Flag
N=NO
Y=YES
N
Night mode “Only with Clock option”
Flag
N=NO
Y=YES
N
DPOFFSET
bar
0
8
2
Serial Card
On/off remote
Cool/heat remote
TMAX
°C
-20
50
30
DELTA-V
Volt
0.0
5.0
5
T MIN
°C
-20
30
-2
DELTA V
Volt
0
5
5
Set point
°C
- 20 °C
99,9
- 20°C
Diff.
°C
0
99,9
0,5
Min.T air
°C
- 20 °C
99,9
00.0
Min.twin air temp.
Set point
Press key ENTER for reset history
Press the ENTER key to erase the alarm history memory
Press the key ENTER for default values
Press the ENTER key to go back default value
Warning: Carry out this operation whenever the eprom is changed
Insert the new service password
1234
Note 2: Set this parameter to FSC only if the speed controller is available, otherwise set it to STEP.
9
VLS/VLH 09/05
2.3.10 MANUFACTURER LEVEL KEY
Press the “menu” + “prog” keys at the same time, under a valid access code (4939), to enter the Manufacturer Level.
The parameters are available only in Italian.
User parameters
Type
Min. Value
Max. Value
Default
Enter password
Manifactured
Exact password
0000
0
9999
4939
Flag
Chiller
Heat pump
VLS: Chiller
VLH: Heat pump
N°
1
2
2
-
BTB - TWO CIR - DUAL
Unit
Number of compressor per circuit
LWT sensor Log
Enable sensor
B1:Y
B2:Y
B4:Y
B5:N
B7: Y
B8:Y
B3:N
B6:N (See note)
Liquid solenoid valve
( Note )
Flag
B5 = N For chiller
B6 = N For chiller
N=NO
DUAL
B5 = Y For heat pump
B6 = Y For heat pump
Y=YES
Y
Cycle rev. valve
Flag
NA
NC
NA
Analog inputs
Range
0-1 V
4-20 mA
0-1 V
Start
-30° C
End
90°C
0 bar
30 bar
Start
0 bar
End
30 bar
Tcoil os Lp
Analog inputs
Range
High pressure DP
…………….
Hour autoreset numbers
LP 1 alarm
N°
0
99
3
LP 2 alarm
N°
0
99
3
Term.comp 1
N°
0
99
1 VLS / 3 VLH
Term.comp 2
N°
0
99
1 VLS / 3 VLH
Term.comp 3
N°
0
99
1 VLS / 3 VLH
Term.comp 4
N°
0
99
1 VLS / 3 VLH
Term.fan
N°
0
99
1
Antifreezing
N°
0
99
1
Push the ENTER key
to initialize the unit
Warning
Carry out this operation whenever the eprom is changed
Set the new manufacturer’s
password…….
0000
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VLS/VLH 09/05
3
THERMOSTAT CONFIGURATION
(VLH only)
charges also the other compressor of the tandem and
resets at 115°C.
One thermostat is mounted for each tandem of compressors. The thermostat is used to control the tandem scroll
discharge temperature. Above 125 °C it discharges a
compressor and resets at 105 °C. Above 135 °C it dis-
Note: configure the dP parameter in oF before all the
other parameters.
Parameter
Description
Range
Default
Unit
SET 1
SET-POINT
LS-HS
120
°C
SET 2
SET-POINT
LS-HS
125
°C
d1
DIFFERENTIAL
-99 / 240
-20
°C
d2
DIFFERENTIAL
-99 / 240
-20
°C
LS1
MINIMUM SET
-70 / 999
0
°C
LS2
MINIMUM SET
-70 / 999
0
°C
HS1
MAXIMUM SET
-70 / 999
150
°C
HS2
MAXIMUM SET
-70 / 999
150
°C
od
RELAY DELAY
0 / 500
0
seconds
CAL
OFFSET SENSOR
-99 / 999
0
°C
Ft
OPERATING MODE
on / nr
on
Flag
OCO
SET-POINT TYPE
di / in
in
Flag
HC1
OPERATING MODE
C/H
H
Flag
HC2
OPERATING MODE
C/H
H
Flag
rP1
RELAY STATUS: ALARM
ro / rc
ro
Flag
rP2
RELAY STATUS: ALARM
ro / rc
ro
Flag
LF1
LED STATUS
di / in
di
Flag
LF2
LED STATUS
di / in
di
Flag
dP
DECIMAL POINT
oF / on
oF
Flag
hdd
RESOLUTION
n/y
n
Flag
tAb
CONFIGURATION
/
/
/
11
VLS/VLH 09/05
4
EPROM CHANGE pCo
4.1
NEW EPROM HAS NO EFFECT YET
Enter in factory level (press simultaneusly Menu + Prog
and enter password 4939)
1. Check if address board is already fitted on pCO
board, if not add it (look at “clock” labelled socket
on pCO) and set only dip1 to ON
scroll masks until you find:
2. Check if terminal display is addressed with
(dip1,2,3,4 = ON).
Premere tasto ENTER
per inizializzare
l'unità
3. Replace the eprom with new one
4. Power on the control pressing in the same time both
arrow keys and enter until
Press enter to initialize the pCO control to new eprom:
in the end of initializing:
Terminal Adr: 15
I/O Board Adr: -
Premere tasto ENTER
per inizializzare
l'unità
Use ARROWS and ENTER to set I/O Board Adr a 1:
OPERAZIONE ESEGUITA!
Terminal Adr: 15
I/O Board Adr: 1
Now you have to off the pCO and on it again.
Now pCO is programmed with standard default parameters value as cooling only unit.
Press ENTER:
Terminal Config
Press ENTER
to continue
Enter
–
P:01 Adr
Trm1 15
Trm2 None
Trm3 None
Priv/Shared
Pr
--- Ok?--
Press ENTER and set the following mask accordingly:
P:01 Adr
Trm1 15
Trm2 None
Trm3 None
Priv/Shared
Pr
--- Ok? Yes
Press ENTER to confirm now the pCo is configurate.
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VLS/VLH 09/05
5
COMPRESSORS LEAVING
LIQUID CONTROL
(COOLING MODE)
If the LWT falls below the SetPoint High Limit and
greater than the SetPoint Low Limit, temp is in the
Neutral Band. No actions is occurring. No load and no
unloading.
If Leaving Control mode is selected, the leaving mixed
water temperature LWT will be controlled between the
setpoint and the setpoint + Neutral Band. The SetPoint
High Limit is the Setpoint plus the Neutral Band. The
SetPoint Low Limit is the Setpoint.
If the LWT falls below the SetPoint one compressor is
switched off. Until the LWT is below the Setpoint, compressors are unloaded according to the Unload time
parameter value.
If the mixed leaving water temperature LWT is above
the SetPoint High Limit, the compressors will be energized one by one separated by the Time between Start
and Start different compressors
6
COMPRESSORS LEAVING
LIQUID CONTROL
(HEATING MODE)
If the LWT is between the SetPoint Low Limit and the
SetPoint High Limit, temp is in the Neutral Band. No
actions is occurring. No load and no unloading.
If leaving Control mode is selected, the leaving mixed
water temperature LWT will be controlled between the
setpoint and the setpoint - Neutral Band. The SetPoint
High Limit is the Setpoint. The SetPoint Low Limit is the
Setpoint – Neutral Band.
If the LWT is above the SetPoint High Limit one compressor is switched off. Until the LWT is above the Setpoint
High Limit, compressors are unloaded according to the
Unload time parameter value.
If the mixed leaving water temperature LWT is below the
SetPoint Low Limit, the compressors will be energized
one by one separated by the Time between Start and
Start different compressors.
13
VLS/VLH 09/05
7
COMPRESSORS RETURN LIQUID
CONTROL (COOLING MODE)
If the RWT is above the Sepoint, control starts to load
each stages. The higher is the RWT, the more compressors will be loaded, according to the compressor activity logic, timer and rules described.
If Return Control Mode is selected, the return water temperature RWT is controlled between the Setpoint and
the Setpoint + Proportional Band. We call this zone: the
Loading Zone.
All stages, 2 or 4 compressors, are placed in the proportional band, dividing it in the number of the compressors.
Example: regulation diagram for machines with max. 4 compressors:
All the unit compressors will be proportionally positioned in the band called Loading Zone.
8
COMPRESSORS RETURN LIQUID
CONTROL (HEATING MODE)
The difference is that the loading zone is between Set
Point – Proportional Band and Set Point.
The compressors are loaded in the same proportional
way used in Return Control in Cooling.
14
VLS/VLH 09/05
9
CONDENSER FAN CONTROL
(IN COOLING MODE
WITH FAN SPEED CONTROL)
As soon as the first compressor starts, the fan relay will
turn on, and it will stay on until the all compressors turn
off. For the first 10 seconds the fans will begin at an output level proportional to the ambient temperature. The
hotter it is out, the faster the fans will start. Below is a
chart showing the correlation.
Parameter used: Minimum Fan Speed, Max Fan Speed,
Discharge Pressure Set (DPSET), Max Discharge Pressure,
MINDP, Condensation type Control (STEP or FSC).
Control uses one digital output to power on one fans
relay and an analogue output 0-10Vdc to drive a Fan
Speed Controller (FSC). The fans try to maintain a constant condenser pressure equal to the programmed set
point by varying fan speed.
Table 1 – Startup Fan Values
is running at lower capacity as long as neither pressure
exceeds the maximum discharge pressure.
There is one high pressure transducer each system. If
only one compressor is running, the fans control to its
discharge pressure. If two compressors are running, the
fans control the pressure of the 1st system started, or the
one which is running at 100% capacity if the other one
Once on, the fan speed is recalculated every second
according to the below basic rules:
If DPSET-1 < DP < DPSET+1 then no change in AO
If (DPSET+1 < DP < DPSET+2) AND (DP IS NOT DECREASING) then AO = AO + 1 %
If (DP > DPSET + 2) AND (DP IS NOT DECREASING) then AO = AO + 5 %
If (DPSET-2 < DP < DPSET-1) AND (DP IS NOT INCREASING) then AO = AO -1%
If (DPSET-2 < DP < 10.5) AND (DP IS NOT INCREASING) then AO = AO -2%
If (DP < MINDP) then AO = AO - 2 %
To check if DP is increasing or decreasing, value DDP = ± 0.2 bar/sec is used.
15
VLS/VLH 09/05
10
CONDENSER FAN CONTROL
(COOLING MODE) IN STEP
The fan step control is managed by the parameters LP1-HP1-LS-Diff
The fans start under sensor air (B4)control OAT
During the fans running :
If DP>HP1 one step is load independent by OAT value
If DP<LP1 unloaded the step
DP is the leader between the two transducer
LS - Default = Peer fans -10°C Odd fans -20°C
DIFF - Default = Peer/Odd 45°C
HP1 - Default = 21 bar (R410C) 14 bar (R134A)
LP1 - Default = 13 bar (R410C) 7 bar (R134A)
16
VLS/VLH 09/05
11
CONDENSER FAN CONTROL
IN HEATING WITH FSC
Two parameters used: Low Air Temp Heating and High
Air Temp Heating.
pressure. At unit startup, the fans will run for 3 seconds
at max speed before the compressor starts.
If the Tair probe is installed, fan control in heat pump
mode is always based on ambient temperature and not
After startup, the fans will run according to the following
rule:
If Tair < Low Air Temp Heating then AO = Max Fan Speed
If Low Air Temp Cooling < Tair < High Air Temp Cooling then AO from Max to Min with
linear progression
If Tair > High Air Temp Heating then AO = Min Fan Speed
If Air Temp Probe (B4) isn’t installed, the Analogue
Output is forced to the 10Vdc value. The Fan relay is
energized whenever at least one compressor is running.
If High pressure transducer are installed, during the
defrost cycle, the fans will turn on at 20Bar and run at
50%. AO = 5Vdc. The fans will stay on until the higher
discharge pressure drops to 15 Bar, and then they will
turn off.
17
VLS/VLH 09/05
12
CONDENSER FAN CONTROL
(HEATING MODE) IN STEP
LOW – Default = Odd fans 15°C Peer fans 20°C
HIGH – Default = Peer/Odd fans 30°C
18
VLS/VLH 09/05
13
NIGHT MANAGEMENT
(or LOW NOISE OPTION)
with the CLOCK key, if enabled:
PM = night mode start
AM = night mode end
MAX FAN SPEED IN COOLING IN NIGHT MODE:
The parameter is defined at the Service level: “Night
Mode”. If set to SI, the DPSET is modified as follows:
DPSET night=DPSET+DPOFFSET from PM hours to AM
hours
Where:DPOFFSET = parameter in bars at Service Level.
It is the correction of the pressure target of the condensation control with speed controller.
PM and AM = parameters that can be set with a mask
MaxFanSpeed is no longer a fixed parameter, but is a
function of B4, air temperature
The analogue output value AO, is always between the
Min Fan Speed and the Max Fan Speed. Whenever
one of the two high pressure measures by the transducer
14
reaches the MDP Value, soon the fan must run at max
speed, until that high pressure value falls again to the
90% of the Max High Pressure Value.
COMPRESSORS CAPACITY
CONTROL
ning), the high pressure value reaches the setted Disch
Pressure Limit default value 26 bar, the last sys compressor loaded is soon unloaded.
Parameters used: Disch Pressure Limit, (HI) Max Disch
Pressure.(MDP)
If high pressure transducer are installed and if the unit is
a 4 compressors unit, the compressors capacity control
is active.
Second compressor of the system will be allowed to run
only when Sys High Pressure value falls below the Max
Discharge Pressure default value 24 bar.
If, at any time while the sys is full loaded (2 comps run-
19
VLS/VLH 09/05
15
OIL RECOVERY FUNCTION
If one of the tandem (System1-2) running at 50% (only
one compressor running) more than 40’ the control will
force the tandem at 100% for 5 minuts.
16
PUMP CONTROL
When the unit is in Off, always pump runs for 5 mins
every “Pump Stand-by Interval” value, setted in Service
Level. Default must be 12 hours.
Parameters used in Pump management mask: Remote
logic, Stand-by, Delay Stop.
Pump always starts 30 seconds before the first compressor is loaded and stops always a parameter Pump
Delay Time value in seconds after the unit is stopped
locally or by remote start/stop digital input.
If the pump is not controlled by the electronic control put
the stand by value at 00.
If the unit is in stand-by, the pump must anyway be started if the Antifreeze heater is powered or the unit is in
Antifreeze alarm.
If the parameter “Pump Remote Logic” is in YES, if the
unit is stopped by the remote Start/Stop digital input,
the pump continues to run. It only stops if the unit is
locally stopped by panel.
17
PUMP-DOWN LOGIC – LIQUID
LINE SOLENOID VALVE
CONTROL
Each system is equipped with one liquid line solenoid
valve, to feature a pumping down.
Pump Down during start-up of the first compressor of
each system and during stop of the last compressor of
each system.
Pump-down finishes by low pressure, when Low Pressure
Switch opens and/or by maximum time reached. See
the mask and graphs below for further information.
Parameters used: Pump-Down Max Time, Pump-Down
Enable, Liquid Line Solenoid Valve Enable. All the following logic is valid only if Liquid Line Valve are selected as present in Factory Level, and if Pump-Down is
enable in Service Level.
18
DEFROST CYCLE
(HEAT PUMPS ONLY)
Defrosting of a circuit with time/temperature control:
20
VLS/VLH 09/05
It is a Simultaneous Global Defrost.
Parameters used: Defrost start Temp; Defrost stop temp,
defrost Delay time, defrost Max time, Reversing Off
Time. It is possible to set compressor switch off time
(Reversing Off parameter) when system enter and exit
from defrost mode. Compressors are not switched off if
time is set to 0 seconds. Moreover cycle reversion during normal operation (changing from summer to winter
mode or back) always follow compressors switch off.
During defrost cycle, if the discharge pressure in one of
the two systems, reaches an high dangerous value, fans
must run at max speed. So, if discharge pressure transducer are attached, if one of the two high pressure values reaches the Max Discharge Pressure value (see
MDP) the fans contactor is energized and the analogue
output is forced to 5Vdc.
Defrost cycle stops when both the Tcoil values rises up
to the Defrost Stop Temp value, anyway if the Defrost
Max Time has elapsed.
If one of the two Tcoil probes temperature values fall
below the Defrost start Temp, a timer starts. The timer is
increased while the Tcoil value is under the Defrost start
Temp. When the timer (t1 + t2 + t3 + …) reaches the
defrost start time value, the defrost cycle starts for both
system.
When defrost cycle is ended, the reverse valve is
unpowered and fans are powered again, according to
fans rule logic.
During defrost cycle, fans are stopped, all compressors
run (if one or more are in off, they must be powered),
reverse valve is powered.
19
VLS-VLH TROUBLE SHOOTING
The following table details possible unit faults, their probable cause and suggested remedies, for any other problems
not immediately recognisable and/or technical assistance, call an authorised Technical Service Center.
Faulty
Probable cause
Remedy
AL01
Efficiency alarm CPS
Gas circuit empty
Wrong compressors rotation
To charge the circuit
To check the electrical connection
AL02
Sys 1
Antifreezing
Low water flow
Wrong pump
Water filter dirty
Dirty exchanger
High circuit pressure drop
To check the pump
To check the pump size
To clean the filter
To clean the exchanger
To check the plant pressure drop
AL03
Sys 2
Antifreezing
Low water flow
Wrong pump
Water filter dirty
Dirty exchanger
High circuit pressure drop
To check the pump
To check the pump size
To clean the filter
To clean the exchanger
To check the plant pressure drop
AL04
Flow meter
Water pump stop
Water pump blocked
Pump thermal contact open
Flow switch blocked
To check the pump
To release the pump
To reset the thermal contact and to check
the scale
To release the flow switch
AL05
Sys 1
Low pressure
Espansion valve broken
Gas circuit empty
Gas leak
High temperature water inlet
Solenoid valve not open
Solenoid valve not open
To replace the espansion valve
To charge the circuit
To find and repair the leak
To check the plant thermal load
To check the electrical connection
To check Pump Down setting
AL06
Sys 2
Low pressure
Espansion valve broken
Gas circuit empty
Gas leak
High temperature water inlet
Solenoid valve not open
Solenoid valve not open
To replace the espansion valve
To charge the circuit
To find and repair the leak
To check the plant thermal load
To check the electrical connection
To check Pump Down setting
21
VLS/VLH 09/05
Faulty
Probable cause
Remedy
AL07
Sys 1
High pressure
COOL
Fan stop
Low ventilation
Fan thermal contact open
High gas charge
Coil dirty
Coil obstruct
Faulty high pressure transducer
To check the fan
To check the fan speed
To reset the contact
To check the gas charge
To clean the coil
To check the installation position
To replace the transducer
HEAT
Low water flow
Wrong pump
Dirty filter
Dirty exchanger
High circuit pressure drop
To check the pump
To check the pump size
To clean the filter
To clean the exchanger
To check the plant pressure drop
COOL
Fan stop
Low ventilation
Fan thermal contact open
High gas charge
Coil dirty
Coil obstruct
Faulty high pressure transducer
To check the fan
To check the fan speed
To reset the contact
To check the gas charge
To clean the coil
To check the installation position
To replace the transducer
HEAT
Low water flow
Wrong pump
Dirty filter
Dirty exchanger
High circuit pressure drop
To check the pump
To check the pump size
To clean the filter
To clean the exchanger
To check the plant pressure drop
AL11
Thermal switch
compressor 1
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL12
Thermal switch
compressor 2
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL13
Thermal switch
compressor 3
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL14
Thermal switch
compressor 4
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL08
Sys 2
High pressure
22
VLS/VLH 09/05
Faulty
Probable cause
Remedy
AL15
Thermal switch
fans
Fan stop
Fan thermal contact open
Fan blocked
Wrong electrical cable connection & phase
missing
To check the motor
To reset the thermal contact and to check
the scale
To release the fan
To check the electrical connection,
to tighten the terminal block screws
AL21
Failure sensor B1
Entering water
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL22
Failure sensor B2
Outlet water
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL23
Failure sensor B3
Outlet water
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL24
Failure sensor B4
Outdoor air
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL25
Failure sensor B5
Coil 1
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL26
Failure sensor B6
Coil 2
temperature
Faulty sensor
Cut cable
Sensor not connected
Water inside the sensor
To replace the sensor
To replace cable
To check the electrical connection
To check the insulation
AL27
Failure sensor B7
Transducer
High pressure
Circuit 1
High pressure transducer damaged
Cut cable
Water inside the transducer
Connector loose
To replace the transducer
To check the cable
To check the insulation
To tighten the connector screws
AL28
Failure sensor B8
Transducer
High pressure
Circuit 2
High pressure transducer damaged
Cut cable
Water inside the transducer
Connector loose
To replace the transducer
To check the cable
To check the insulation
To tighten the connector screws
AL31
Compressore 1
Mantenance
Exceeded hours of operation compressor 1
To do mantenance
AL32
Compressore 2
Mantenance
Exceeded hours of operation compressor 2
To do mantenance
AL33
Compressore 3
Mantenance
Exceeded hours of operation compressor 3
To do mantenance
23
VLS/VLH 09/05
Faulty
Probable cause
Remedy
AL34
Compressore 4
Mantenance
Exceeded hours of operation compressor 4
To do mantenance
AL35
Pump
Mantenance
Exceeded hours of operation pump
To do mantenance
AL55
Clock damage
Failure of clock card
Clock faulty
Clock cardout of support
To replace the clock
To insert the clock card in the support
AL56
Thermal switch
compressor 1
Only with
“AUTO RESET”
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL57
Thermal switch
compressor 2
Only with
“AUTO RESET”
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL58
Thermal switch
compressor 3
Only with
“AUTO RESET”
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL59
Thermal switch
compressor 4
Only with
“AUTO RESET”
Motor compressor faulty
Compressor thermal contact open
Wrong charge
Wrong electrical cable connection & phase
missing
To check the compressor motor
To reset the thermal contact
To check the gas charge
To check the electrical connection,
to tighten the terminal block screws
AL60
Sys 1
Low pressure
Only with
“AUTO RESET”
Espansion valve broken
Gas circuit empty
Gas leak
High temperature water inlet
Solenoid valve not open
Solenoid valve not open
To replace the espansion valve
To charge the circuit
To find and repair the leak
To check the plant thermal load
To check the electrical connection
To check Pump Down setting
AL61
Sys 2
Low pressure
Only with
“AUTO RESET”
Espansion valve broken
Gas circuit empty
Gas leak
High temperature water inlet
Solenoid valve not open
Solenoid valve not open
To replace the espansion valve
To charge the circuit
To find and repair the leak
To check the plant thermal load
To check the electrical connection
To check Pump Down setting
AL62
Thermal switch
fans
Only with
“AUTO RESET”
Fan stop
Fan thermal contact open
Fan blocked
Wrong electrical cable connection & phase
missing
To check the motor
To reset the thermal contact and to check
the scale
To release the fan
To check the electrical connection,
to tighten the terminal block screws
AL63
Sys 1-2
Antifreezing
Only with
“AUTO RESET”
Low water flow
Wrong pump
Water filter dirty
Dirty exchanger
High circuit pressure drop
To check the pump
To check the pump size
To clean the filter
To clean the exchanger
To check the plant pressure drop
24
VLS/VLH 09/05
20
LIST OF ITELCO-CLIMA APPLICATION SUPERVISOR
VARIABLES FOR PCO APPLICATION CHILLER/HEATPUMP: VLS – VLH
Level: 1=User (Site manager); 2=Service Manager; 3=Manufacturer; n.c.=not care
Valid for EPROM 031B10210-I02
Index
Meaning
Read/Write
Range
1
Water inlet temperature (RWT)
Read
-50.0 ÷ +105.0 °C
2
Water outlet temperature (LWT)
Read
-50.0 ÷ +105.0 °C
4
External air temperature (OAT)
Read
-50.0 ÷ +105.0 °C
5
System #1 defrost temp.
Read
-50.0 ÷ +105.0 °C
6
System #2 defrost temp.
Read
-50.0 ÷ +105.0 °C
7
System #1 high pressure transducer
Read
0.0 ÷ 30.0 bar
8
System #2 high pressure transducer
Read
0.0 ÷ 30.0 bar
9
Regulation temperature (RWT or LWT)
Read
-50.0 ÷ +105.0 °C
10
Fan speed index
Read
0.0 ÷ 10.0
11
Cooling LWT compressor stop threshold
Read/Write
-20.0 ÷ +20.0 °C
12
Heating LWT compressor stop threshold
Read/Write
20.0 ÷ + 60.0 °C
13
Antifreeze setpoint
Read/Write
-15.0 ÷ +10.0 °C
17
Discharge pressure setpoint
Read/Write
10.0 ÷ 24.0 bar
20
Maximum Discharge pressure
Read/Write
10.0 ÷ 28.0 bar
21
Discharge pressure limit
Read/Write
18.0 ÷ 28.0 bar
22
High temperature heating
Read/Write
0.0 ÷ 99.9 °C
23
Low temperature heating
Read/Write
0.0 ÷ 99.9 °C
26
Minimum cooling setpoint limit (mCS)
Read/Write
5.0 ÷ 12.0 °C
27
Maximum heating setpoint limit (MHS)
Read/Write
30.0 ÷ 55.0 °C
53
RWT cooling setpoint
Read/Write
mCS+2 ÷ 20.0 °C
54
LWT cooling setpoint
Read/Write
mCS ÷ 20.0 °C
55
RWT heating setpoint
Read/Write
MHS-5 ÷ 40.0 °C
56
LWT heating setpoint
Read/Write
MHS ÷ 40.0 °C
57
RWT glycol cool setpoint
Read/Write
-15.0 ÷ 20.0 °C
58
LWT glycol cool setpoint
Read/Write
-15.0 ÷ 20.0 °C
59
Band
Read/Write
1.0 ÷ 10.0 °C
60
Neutral zone
Read/Write
1.0 ÷ 6.0 °C
61
Low speed setpoint
Read/Write
-20.0 ÷ 0.0 °C
62
Low speed differential
Read/Write
0.0 ÷ 99.9 °C
64
DPOFFSET (night mode)
Read/Write
0.0 ÷ 8.0 bar
65
TMAX (night mode)
Read/Write
-20.0 ÷ 50.0 °C
67
Minimum tandem air temperature setpoint
Read/Write
-20.0 ÷ 99.9 °C
68
Minimum tandem air temperature differential
Read/Write
0.0 ÷ 99.9 °C
25
VLS/VLH 09/05
Index
Meaning
Read/Write
bit = 0
bit = 1
1
Heating operation
Read
Cool
Heat
3
System #1 compressor #1
Read
off
On
4
System #1 compressor #2
Read
off
On
6
System #2 compressor #1
Read
off
On
7
System #2 compressor #2
Read
off
On
9
Fan
Read
off
On
11
4-way valve
Read
off
On
12
System #1 alarm
Read
run
Alarm
13
System #2 alarm
Read
run
Alarm
14
Pump
Read
not run
Run
15
RWT/LWT temperature control
Read/Write
RWT
LWT
16
Automatic restart
Read/Write
no
Yes
17
Enable operation with glycol
Read/Write
no
Yes
22
Disable system #1
Read/Write
off
On
23
Disable system #2
Read/Write
off
on
24
Enable chiller/heatpump remote selection
Read/Write
no
yes
29
Enable B5 probe (it means unit is heatpump)
Read
no B5
yes B5, hp
33
Unit on
Read
off
on
34
On/Off from supervisor
Write
off
on
40
System #1 antifreeze
Read
no alarm
yes alarm
41
System #2 antifreeze
Read
no alarm
yes alarm
42
System #1 low pressure
Read
no alarm
yes alarm
43
System #2 low pressure
Read
no alarm
yes alarm
44
System #1 high pressure
Read
no alarm
yes alarm
45
System #2 high pressure
Read
no alarm
yes alarm
46
Compressor #1 overload
Read
no alarm
yes alarm
47
Compressor #2 overload
Read
no alarm
yes alarm
48
Compressor #3 overload
Read
no alarm
yes alarm
49
Compressor #4 overload
Read
no alarm
yes alarm
50
Fan overload
Read
no alarm
yes alarm
51
B1 faulty probe
Read
no alarm
yes alarm
52
B2 faulty probe
Read
no alarm
yes alarm
54
B4 faulty probe
Read
no alarm
yes alarm
55
B5 faulty probe
Read
no alarm
yes alarm
56
B6 faulty probe
Read
no alarm
yes alarm
57
B7 faulty probe
Read
no alarm
yes alarm
58
B8 faulty probe
Read
no alarm
yes alarm
59
Compressor #1 maintenance
Read
no maint.
yes maint.
60
Compressor #2 maintenance
Read
no maint.
yes maint.
61
Compressor #3 maintenance
Read
no maint.
yes maint.
62
Compressor #4 maintenance
Read
no maint.
yes maint.
63
Flow switch alarm
Read
no alarm
yes alarm
67
Enable night mode
Read/Write
off
on
69
Winter
Read/Write
Cooling
Heating
26
VLS/VLH 09/05
Index
1
Meaning
System #1 state
Read/Write
value/range
Read
0 = off
System #1 state
1 = pumpdown
System #1 state
2 = 1 comp running
System #1 state
3 = 2 comp running
System #1 state
4 = sys in alarm
2
System #2 state
Read
3
Machine state
Read
as per sys 1 status
0 = on
Machine state
1 = off by alarm
Machine state
2 = off by supervisor
Machine state
3 = off by low OAT
Machine state
4 = off by remote
Machine state
off
9
Pump stand-by time
Read/Write
01 – 24 hours
10
Pump power off delay
Read/Write
00 – 60 sec
11
Flow switch alarm delay under steady conditions
Read/Write
00 – 99 sec
12
Flow switch alarm delay at the start-up
Read/Write
00 – 99 sec
25
Pump hours (high part)
Read/Write
*
26
Pump hours (low part)
Read/Write
*
27
Compressor #1 hours (high part)
Read/Write
*
28
Compressor #1 hours (low part)
Read/Write
*
29
Compressor #2 hours (high part)
Read/Write
*
30
Compressor #2 hours low part)
Read/Write
*
31
Compressor #3 hours (high part)
Read/Write
*
32
Compressor #3 hours (low part)
Read/Write
*
33
Compressor #4 hours (high part)
Read/Write
*
34
Compressor #4 hours (low part)
Read/Write
*
37
Night mode start hour (PM)
Read/Write
00 – 12
38
Night mode start minutes
Read/Write
00 – 59
39
Night mode end hour (AM)
Read/Write
00 – 12
40
Night mode end minutes
Read/Write
00 – 59
Note *: running hours range is between 000000 and 999999. Generally Low Part means the last 3 figures: XXX999;
and high part is the first 3 figures: 999XXX.
27
VLS/VLH 09/05