Guardian SCC 40 User manual

Page 1
GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
GUARDIAN
SCC
40/35/30/25
Screw Compressor Controllers
•Compressor status monitor with pressure, temperature, slide and load
displays
•Control by suction pressure setpoint or remote 5th pressure
•Control by suction equivalent temperature setpoint or remote 5th
temperature
•Alarm and trip monitoring
•Compressor, pump, slide and speed control
•Economiser, heater and liquid injection control
•Optional Automatic volumetric slide control
•Multiple compressor system control
•Local panel operation and set-up
•Communications for remote monitoring and set-up
•Auto VI Control
Operation and Set-up Manual
GUARDIAN SCC-40/35/30/25 Screw Compressor Controllers provide suction pressure
setpoint control and alarm monitoring for one screw compressor. Alternatively the unit may
be set-up to control on water chiller, glycol chiller or equivalent temperature.
GUARDIAN
Tel. [phone]
Fax. [phone]
Email: [email protected]
www.Guardian-controls.com

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
Contents
GUARDIAN ............................................................................................... 1
SCC........................................................................................................... 1
40/35/30/25................................................................................................ 1
GETTING STARTED................................................................................. 4
BUTTON OPERATION SHORTHAND...............................................................................5
HARDWARE CONFIGURATION CHECKS .......................................................................5
CONFIGURE UNIT MODEL, SYSTEM No & ADDRESS...................................................6
Enter Passcode..............................................................................................................6
Select Unit Model............................................................................................................6
Select System No and Address ......................................................................................7
RS485 Communications.................................................................................................7
UNIT MODELS.......................................................................................... 8
OVERVIEW........................................................................................................................8
Functions........................................................................................................................8
Displays..........................................................................................................................9
Pushbuttons....................................................................................................................9
GENERAL SPECIFICATION...........................................................................................11
Consultant Format .........................................................................................................12
AVAILABLE UNIT MODELS ...........................................................................................13
SCC-40 Input/Output Signals.......................................................................................14
SCC-40 Termination Wiring -........................................................................................15
SCC-35 Input/Output Signals.......................................................................................16
SCC-35 Termination Wiring -........................................................................................17
SCC-30 Input/Output Signals........................................................................................18
SCC-30 Termination Wiring -........................................................................................19
SCC-25 Input/Output Signals........................................................................................20
SCC-25 Termination Wiring..........................................................................................21
OPERATION ........................................................................................... 22
SCC40 PANEL LAYOUT.................................................................................................22
LED LAMPS. ................................................................................................................23
SYSTEM STATUS DISPLAYS......................................................................................24
SAFETY TRIP INDICATIONS.......................................................................................27
DISPLAY PUSHBUTTON OPERATION .......................................................................28
‘view’.............................................................................................................................28
‘type’.............................................................................................................................28
CONTROL PUSHBUTTON OPERATION........................................................................31
“mode”..........................................................................................................................31
“Mode-MANUAL”..........................................................................................................31
“Mode-AUTOMATIC”....................................................................................................31
“RESET”.......................................................................................................................31
“Call Frig Engineer”.......................................................................................................32
“stop”............................................................................................................................32
“start”............................................................................................................................32
“Lower”.........................................................................................................................32
“Raise”..........................................................................................................................32
SETTINGS CHANGE PUSHBUTTON OPERATION........................................................33
“next”............................................................................................................................33
“Accept”........................................................................................................................33
“raise”...........................................................................................................................33

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
“Lower”.........................................................................................................................33
“RESET”.......................................................................................................................33
ALARM ACCEPT AND RESET PUSHBUTTON OPERATION........................................34
SETPOINTS.....................................................................................................................36
CONTROL MODES .........................................................................................................38
CONTROL............................................................................................... 39
COMPRESSOR CONTROL OPERATION.......................................................................39
POWER UP..................................................................................................................39
READY/WAITING.........................................................................................................39
STARTING ...................................................................................................................40
RUNNING.....................................................................................................................41
STOPPING...................................................................................................................42
MODES CHANGES......................................................................................................43
TWO SPEED MOTOR CONTROL...................................................................................44
MANUAL MODE 2-SPEED...........................................................................................44
VARIABLE SPEED MOTOR CONTROL.........................................................................44
TWO COMPRESSOR-SINGLE MOTOR OPERATION....................................................47
AUTOMATIC STANDBY COMPRESSOR CHANGEOVER AFTER TRIP.......................50
NOTES ON SET-UP OF AUTO VI FOR HOWDEN COMPRESSOR.... 51
Auto VI Operation:..........................................................................................................51
Procedure.......................................................................................................................52
Auto VI Commissioning Parameters.............................................................................53
Auto VI Drawing............................................................................................................55
Auto VI Wallbox Wiring.................................................................................................56
TIMER SETPOINTS.........................................................................................................57
SETUP..................................................................................................... 59
Compressor Settings.....................................................................................................59
Unit Settings:................................................................................................................59
System Settings............................................................................................................60
Port Settings.................................................................................................................61
Analog..........................................................................................................................61
Test ..............................................................................................................................62
Done.............................................................................................................................62
TWO SPEED MOTOR CONTROL SELECTION...........................................................63
TRANSDUCER SETUP & CALIBRATION...................................................................64
COMMUNICATIONS............................................................................... 67
MAIN SET-UP/ COMMISSIONING PARAMETERS .............................. 68
Setup / Commissioning Parameters .............................................................................71
PRESSURES ...............................................................................................................71
TEMPERATURES........................................................................................................72
EQUIVALENTS ............................................................................................................72
DIFFERENTIALS..........................................................................................................73
TIMERS........................................................................................................................74
Settings display and change facilities..........................................................................75
SCC-40 Enclosure wiring: for trips negative................................................................77
SCC-40 Enclosure wiring: for trips positive.................................................................78
Local Communications..................................................................................................79
Standard Wallbox Internal wiring ..................................................................................80
Standard SCC 40 Drawing............................................................................................81
FITTING NEW EPROM........................................................................... 82
Index................................................................................................................................83

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
GETTING STARTED
Guardian Controllers provide refrigeration engineers with
•ULTIMATE FLEXIBILITY
•ASSURED MONITORING
•RELIABLE ALARMS
This manual provides refrigeration designers, installers, service mechanics and supermarket
personnel with the necessary information to achieve the above objectives.
All users require to know a few basic facts about this controller before successfully starting to
perform their design, commissioning, maintenance or operating functions.
a) All GUARDIAN controllers need to be set up with a unit model selection and other basic
settings for setpoints, timers and addresses.
b) The shorthand used in the following chapters for concisely expressing button pressing and
selection sequences to do all this set-up needs to be understood.
c) Mains power input voltage and hardware switch and link option selections (if any are
required) must correspond to the selected unit model configuration.
d) Since each controller can be configured in a number of different ways to perform flexible
refrigeration control then an understanding of how to find out what unit model is currently
selected, what it does and how it is connected, is also necessary.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
BUTTON OPERATION SHORTHAND
To assist in easy set-up of control setpoints, delays, timers and other configuration settings,
the sequence of button presses and subsequent displays will be shown in this handbook as
below:
ii) A button symbol, followed by text means press that button. “@accept”
iii) A double button, followed by text means press that button repeatedly. “@:@raise”
iv) A display box with the window above it shows the result of the last button press on
the display.
DISCHARGE FILTER
==== 2.0b “@:@raise”
DISCHARGE FILTER
==== 2.5b
v) DISCHARGE FILTER DISCHARGE FILTER
H.P. ==== trip ====
Means the display alternately flashes between identifier and trip message
HARDWARE CONFIGURATION CHECKS
Prior to switching on the GUARDIAN controller check that the hardware unit is the correct
type for the incoming mains voltage.
When satisfied that the correct type of controller is available then the following checks should
be made prior to controller installation or replacement
a) Ensure mains supply is wired correctly to the appropriate TERMINAL WIRING drawing for
the model selected.
b) Ensure that any transducer selector switches specified on the TERMINAL WIRING
diagram are in the correct state.
c) Ensure any shorting link selector pins specified on the TERMINAL WIRING diagram are
correctly fitted.
d) Ensure that probes are wired to the terminal WIRING DIAGRAM and the correct type of
thermistor or pressure transducer probes are fitted.
e) The RS485 highway connections (if required) are wired to the correct terminals and the
screen drain wire is continuous to earth.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
CONFIGURE UNIT MODEL, SYSTEM No & ADDRESS
Enter Passcode
Before any permanent change of controller settings are made then the correct entry of the
appropriate passcode is necessary.
The settings available for change on each passcode are as follows; Passcode
Passcode level 1 setpoints, low & high alarm settings 07
Passcode level 2 low & high trip settings and all level 1 09
Passcode level 3 system settings and levels 1 & 2 15
Enter passcode 15
DISCHARGE FILTER “@view”= “SETPOINT” “@next” “@next”
pASS codE
DISCHARGE FILTER DISCHARGE FILTER
==-= ==12 “@:@raise”==-= ==15 “@accept”
Press “view” to select “SETPOINT”, then press the “next” button twice to enter
the passcode settings.
Press “raise” repeatedly until passcode 15 is selected and then press “accept”
Select Unit Model
Enter Passcode as button sequence above.
“@:@view”= “SYSTEM”
SUCTION OIL “@:@type”= “SAFETY TRIPS”
==sE tUP=
DISCHARGE FILTER
==== =yEs “@accept”
DISCHARGE FILTER DISCHARGE FILTER
==== Unit “@accept”==== SC30 “@:@raise”
DISCHARGE FILTER
==== SC40 “@accept”
Press ‘view’ repeatedly until ‘SYSTEM’ is selected.
Press ‘type’ repeatedly until ‘SAFETY TRIPS’ is selected. Press ‘accept’
‘Unit’ is displayed press ‘accept’
Display shows unit model currently selected which may be wrong.
Press ‘raise’ repeatedly until correct model is displayed (e.g.SC30) and then press ‘accept’
which causes the display to wink briefly and display the new unit model selection
(e.g SC40 )

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
Select System No and Address
e.g. setup unit for system 65 compressor number 1 at address 195
Enter setup as button sequence as above
SUCTION OIL
==sE tUP=
DISCHARGE FILTER
==== =yEs “@accept”
DISCHARGE FILTER DISCHARGE FILTER
==== Unit “@accept”==== sC40 “@next”
DISCHARGE FILTER DISCHARGE FILTER
==== Sn01 “@:@raise”==== Sn65 “@accept”
DISCHARGE FILTER “@next”
==== Cn01 “@accept”
DISCHARGE FILTER “@next”
==== A=01 “@:@raise”
DISCHARGE FILTER
==== A195 “@accept” “@:@next”
DISCHARGE FILTER
==== donE “@accept”
RS485 Communications
When the correct system number, case/compressor number and highway address have been
entered as above then the controller can communicate with the GUARDIAN Consultant
Terminal PC for central alarm monitoring and temperature display. Control setpoints, defrost
times and alarm limits may then be sent to the controller from the PC.
For further details see page 63

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
UNIT MODELS
Guardian controllers may be configured in a number of different ways dependent on unit
model selection. Each unit model fulfils a different refrigeration temperature monitoring and
control requirement. In order to perform the required refrigeration control then each model
has different uses for the controller’s input output signals. This section gives details of all the
model variations available for the controller and the way to connect the wiring to the plant
devices and measuring transducers.
OVERVIEW
Functions
The GUARDIAN SCC-40 controller provides facilities for:-
MONITORING
Measurement of pressures, temperatures, load and slide inputs for control, alarm and
trip display
Calculation of differential pressures and superheat temperatures for control, alarm and trip
display.
Detection of digital input states or safety trip inputs.
ALARMS
Detection after a preset guardtime of pressure and temperature High/Low alarms when the
compressor is in operation. Alarms are indicated by alternating a =Hi= or =Lo=
message on the appropriate temperature or pressure display.
TRIPS
Detection of pressure and temperature High/Low trips which stop the compressor. Trips are
indicated by the flashing red TRIPPED lamp and an alternating 'TRIP' message on the
appropriate temperature/pressure display.
All measurement values are frozen after detection of a trip condition. This facility provides
information on the compressor state, pressures and temperatures when the trip occurred
until after the RESET pushbutton has been pressed.
Detection of safety trips which stop the compressor.
Trips are indicated by the flashing red TRIPPED lamp and an appropriate message.
Trips vary dependent on pack model configuration.
ie :- L.P. ,H.P. ,LEU=,fLo= alternating with a trIP message on the
appropriate display.
CONTROLS
Oil pump, motor and economiser startup and run sequences using preset timers and limits
Compressor status is indicated by LED lamps on the control panel.
Compressor capacity slide valve raise / lower control dependent on suction pressure or
slide control setpoint. The slide valve is automatically lowered when over-current limit or high
discharge pressure are detected or the compressor is stopped.
Suction pressure or slide control initiation of other compressors in the system via a RS485
link when in REMOTE mode.
Oil heater and liquid injection control on oil sump and discharge temperatures.
Various vi type control outputs including VI control, condenser FAN control, extra injection
and standby compressor.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
Displays
i). SUCTION, DISCHARGE, OIL & FILTER.
SUCTION OIL
2.1b 11.7b 4-digit 7-segment LED displays for display of
measurements setpoints/limits for temperatures and
pressures
DISCHARGE FILTER The contents change dependent on ‘view’ and
10.2b 11.5b ‘type’ selections
ii). CAPACITY%.
CAPACITY%
100 3-digit 7-segment LED displays for display of loading timers
and capacity.
iii). MOTOR LOADING%.
MOTOR LOAD%
105 3-digit 7-segment LED displays for display of timers and
motor load.
iv). COMPRESSOR No.
No
11-digit 7-segment LED display
Pushbuttons.
All pushbuttons are embossed, tactile membrane switches.
start, stop, raise & lower used to control compressors when in manual mode.
RESET used after a trip to reset the compressor.
Mode, view & type used in conjunction with appropriate LED displays to select
control, display or settings change facilities.
accept, next used in conjunction with raise, lower and appropriate LED
displays during setpoint and limit settings changes.
Unaccepted alarms and trips are acknowledged by pressing accept.
Pushbuttons on the local control panel permit operator display of setpoints, pressures,
temperatures, alarm and trip settings and compressor runhours and status.
Setpoints, alarm and trip settings may be changed from the panel after entry of the
appropriate passcode.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
The compressor may be selected to operate in one of three control modes:-
MANUAL, LOCAL or REMOTE MODES.
Safety interlocks, alarm, trip, startup and shutdown sequence controls are automatic in
all three modes.
In MANUAL mode, the each compressor may be individually started and stopped and the
pack capacity raised and lowered by operator pushbutton control from the local panel.
In LOCAL automatic mode, the compressor is started and stopped under control of the
suction pressure setpoint.
REMOTE automatic mode allows up to six RCC-40 units to be connected via a two-wire
communication link (RS485) to provide 6-unit system control.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
GENERAL SPECIFICATION
Power 110 or 230 Vac 50 Hz 30VA (dependent on model type)
Operation 0 to 50ºC
Approx. Dimensions:
Control panel: 300 x 220mm
Control unit: 300 x 230 x 90mm
The GUARDIAN SCC40/35/30/25 control unit comprises a printed circuit board in an
IP65 ABS enclosure for mounting at the rear of the compressor pack control panel with
the display unit mounted on the door and has overall dimensions:- 300 x 230 x 90mm.
The unit is fitted with two-part screw-clamp terminals for the connection of the
appropriate input/output signals. (See input/output section)
The GUARDIAN SCC40 control panel comprises a membrane, pushbutton and display
panel mounted on the front of the control unit.
The membrane front panel has a Black background with white lettering and green buttons
with dimensions 300x220mm.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
Consultant Format
SCC40 Std.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
AVAILABLE UNIT MODELS
The Guardian SCC-40 controllers are available in four models, which vary in facilities
and cost:
SCC-40 4 pressures
4 temperatures
Additional 5th Pressure or 5th Temperature
9 output relays
4 12V dc inputs
5 Mains inputs
8 Trips
2 Analogue outputs
1 Real time clock
SCC-35 3 pressures
3 temperatures
7 output relays
4 12V dc inputs
5 Mains inputs
8 Trips
2 Analogue outputs
1 Real time clock
SCC-30 3 pressures
2 temperatures
7 output relays
4 12V dc inputs
8 Trips
SCC-25 2 pressures
2 temperatures
7 output relays
8 Trips
SCC controllers powered at 110V ac are available on request but require to be set up prior
to delivery.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-40 Input/Output Signals
Analogue inputs
A1 Suction pressure 4 to 20mA -1 to 24 bar g
A2 Discharge pressure 4 to 20mA -1 to 24 bar g
A3 Oil pressure 4 to 20mA -1 to 24 bar g
A4 Filter pressure 4 to 20mA -1 to 24 bar g
A5 Suction temperature PT1000 -50 to 125°C
A6 Discharge temperature PT1000 -50 to 125°C
A7 Oil separator temperature PT1000 -50 to 125°C
A8 Oil heater temperature PT1000 -50 to 125°C
A9 Slide position 0 to 10Vdc 0 to 125%
A10 Load current 0 to 10Vdc 0 to 125%
A11 Chiller temperature ( 5th Temp probe) PT1000 -50 to 125°C
TB10 Chiller pressure or
vibration ( 5th Pressure Transducer) 4-20mA 4-20mA -1 to 24 bar g
0 to 100%
Calculated inputs
A17 Suction equivalent temperature A1(R22/NH3) -50 to 100°C
A18 Discharge equivalent temperature A2(R22/NH3) -50 to 100°C
A19 Suction superheat A17-A5
A20 Discharge diff pressure A2-A1 -1 to 24 bar g
A21 Oil diff pressure A3-A2 -1 to 24 bar g
P_st/no_P/Filt syphen system A3-A1
A22 Filter differential pressure, Filter After Pump
Filter differential pressure, Filter Before Pump A4-A3 A2-A4 -1 to 24 bar g
A23 Compressor hours run 0 to 65000 hrs
Digital inputs
Trip 1 Discharge temperature high dt-H
Trip 2 L.P. cutout L.P.
Trip 3 H.P. cutout H.P.
Trip 4 Oil level LEuL
Trip 5 Oil diff/ flow switch FLO
Trip 6 motor circuit breaker nncb
Trip 7 Emergency stop StoP
Trip 8 Safety (motor thermistor) SFtY
12/24V dc inputs
Input A Slide at 50%/ max demand unload
Input B Optional keyswitch
Input C Slide at minimum 0%
Input D Slide at maximum 100%
Mains inputs
Input E Oil pump running
Input F Compressor running
Input G Refrigeration (inhibit if Rneg)
Input H High setpoint/start
Input I External RESET pushbutton
Relay outputs
R1 Pump motor running 3 Amp inductive 110/240V ac with suppressors
R2 Compressor motor
R3 Slide valve load
R4 Slide valve unload
R5 Economiser
R6 Liquid injection
R7 Oil heater
R8 VI control A orMotor speed LOW or Standby O/P
orInjection 2 of Fans-1
R9 VI control B orMotor speed HIGH or
bypass valve or Fans-2
Analog outputs
AOP1 Capacity control by variable speed motor 0 to 5V dc
AOP2 Motor control speed
Extension outputs
OP1 Not used
OP2 Watchdog
OP3 Not used

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-40 Termination Wiring -
SCC-40 Screw compressor controller.
N.B. The Compressor Run Signal (TB3 Terminal 11) must be supplied to the Controller from the Delta
Contactor of a Star-Delta System, or the Top of Ramp of a Soft Start System.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-35 Input/Output Signals
SCC35
Analogue inputs
A1 Suction pressure 4 to 20mA -1 to 24 bar g
A2 Discharge pressure 4 to 20mA -1 to 24 bar g
A3 Oil pressure 4 to 20mA -1 to 24 bar g
A4 Not used
A5 Suction temperature PT1000 -50 to 125°C
A6 Discharge temperature PT1000 -50 to 125°C
A7 Oil separator temperature PT1000 -50 to 125°C
A8 Not used
A9 Slide position 0 to 10Vdc 0 to 125%
A10 Load current 0 to 10Vdc 0 to 125%
A11 Not used
Calculated inputs
A17 Suction equivalent temperature A1(R22/NH3) -50 to 100°C
A18 Discharge equivalent temperature A2(R22/NH3) -50 to 100°C
A19 Suction superheat A17-A5
A20 Discharge diff pressure A2-A1 -1 to 24 bar g
A21 P_st/no_P/Filt syphen system A3-A1
A22 Filter Diff (Discharge Pressure To Oil Pressure) A2-A3
A23 Compressor hours run 0 to 65000 hrs
Digital inputs
Trip 1 Discharge temperature high dt-H
Trip 2 L.P. cutout L.P.
Trip 3 H.P. cutout H.P.
Trip 4 Oil level LEuL
Trip 5 Oil diff/ flow switch FLO
Trip 6 motor circuit breaker nncb
Trip 7 Emergency stop StoP
Trip 8 Safety (motor thermistor) SFtY
12/24V dc inputs
Input A Slide at 50%/ max demand unload
Input B Optional keyswitch
Input C Slide at minimum 0%
Input D Slide at maximum 100%
Mains inputs
Input E Oil pump running
Input F Compressor running
Input G Refrigeration (inhibit if Rneg)
Input H High setpoint/start
Input I External RESET pushbutton
Relay outputs
R1 Pump motor running 3 Amp inductive 110/240V ac with suppressors
R2 Compressor motor
R3 Slide valve load
R4 Slide valve unload
R5 Economiser
R6 Liquid injection
R7 Oil heater
R8 VI control A or
Motor speed LOW or Standby O/P or
Injection 2 of Fans-1
R9 VI control B or
Motor speed HIGH or
bypass valve or Fans-2
Analog outputs
AOP1 Capacity control by variable speed motor 0 to 5V dc
AOP2 Motor control speed
Extension outputs
OP1 Not used
OP2 Watchdog
OP3 Not used

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-35 Termination Wiring -
SCC-35 Screw compressor controller
N.B. The Compressor Run Signal (TB3 Terminal 11) must be supplied to the Controller from the Delta
Contactor of a Star-Delta System, or the Top of Ramp of a Soft Start System.

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-30 Input/Output Signals
SCC30
Analogue inputs
A1 Suction pressure 4 to 20mA -1 to 24 bar g
A2 Discharge pressure 4 to 20mA -1 to 24 bar g
A3 Oil pressure 4 to 20mA -1 to 24 bar g
A4 Not used
A5 Suction temperature PT1000 -50 to 125°C
A6 Discharge temperature PT1000 -50 to 125°C
A7 Not used
A8 Not used
A9 Slide position 0 to 10Vdc 0 to 125%
A10 Load current 0 to 10Vdc 0 to 125%
A11 Not used
Calculated inputs
A17 Suction equivalent temperature A1(R22/NH3) -50 to 100°C
A18 Discharge equivalent temperature A2(R22/NH3) -50 to 100°C
A19 Suction superheat A17-A5
A20 Discharge diff pressure A2-A1 -1 to 24 bar g
A21 P_st/no_P/Filt syphen system A3-A1
A22 Filter Diff (Discharge Pressure To Oil Pressure) A2-A3
A23 Compressor hours run 0 to 65000 hrs
Digital inputs
Trip 1 Discharge temperature high dt-H
Trip 2 L.P. cutout L.P.
Trip 3 H.P. cutout H.P.
Trip 4 Oil level LEuL
Trip 5 Oil diff/ flow switch FLO
Trip 6 motor circuit breaker nncb
Trip 7 Emergency stop StoP
Trip 8 Safety (motor thermistor) SFtY
12/24V dc inputs
Input A Slide at 50%/ max demand unload
Input B Optional keyswitch
Input C Slide at minimum 0%
Input D Slide at maximum 100%
Mains inputs
Input E Not used
Input F Not used
Input G Not used
Input H Not used
Input I Not used
Relay outputs
R1 Pump motor running 3 Amp inductive 110/240V ac with suppressors
R2 Compressor motor
R3 Slide valve load
R4 Slide valve unload
R5 Economiser
R6 Liquid injection
R7 Oil heater
R8 Not used
R9 Not used
Analog outputs
AOP1 Not used
AOP2 Not used
Extension outputs
OP1 Not used
OP2 Watchdog
OP3 Not used

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-30 Termination Wiring -
SCC30 Screw compressor controller

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GUARDIAN SCC-40 Issue (Auto VI) & V3.6t 07/12/00
SCC-25 Input/Output Signals
SCC25
Analogue inputs
A1 Suction pressure 4 to 20mA -1 to 24 bar g
A2 Discharge pressure 4 to 20mA -1 to 24 bar g
A3 Not used
A4 Not used
A5 Suction temperature PT1000 -50 to 125°C
A6 Discharge temperature PT1000 -50 to 125°C
A7 Not used
A8 Not used
A9 Slide position 0 to 10Vdc 0 to 125%
A10 Load current 0 to 10Vdc 0 to 125%
A11 Not used
Calculated inputs
A17 Suction equivalent temperature A1(R22/NH3) -50 to 100°C
A18 Discharge equivalent temperature A2(R22/NH3) -50 to 100°C
A19 Suction superheat A17-A5
A20 Discharge diff pressure A2-A1 -1 to 24 bar g
A21 Not used
A22 Not used
A23 Compressor hours run 0 to 65000 hrs
Digital inputs
Trip 1 Discharge temperature high dt-H
Trip 2 L.P. cutout L.P.
Trip 3 H.P. cutout H.P.
Trip 4 Oil level LEuL
Trip 5 Oil diff/ flow switch FLO
Trip 6 motor circuit breaker nncb
Trip 7 Emergency stop StoP
Trip 8 Safety (motor thermistor) SFtY
12/24V dc inputs
Input A Not used
Input B Not used
Input C Not used
Input D Not used
Mains inputs
Input E Not used
Input F Not used
Input G Not used
Input H Not used
Input I Not used
Relay outputs
R1 Pump motor running 3 Amp inductive 110/240V ac with suppressors
R2 Compressor motor
R3 Slide valve load
R4 Slide valve unload
R5 Economiser
R6 Liquid injection
R7 Oil heater
R8 Not used
R9 Not used
Analog outputs
AOP1 Not used
AOP2 Not used
Extension outputs
OP1 Not used
OP2 Watchdog
OP3 Not used