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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.
Содержание SCC 25
Страница 12: ...Page 12 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 Consultant Format SCC40 Std ...
Страница 51: ...Page 51 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 Auto VI Drawing ...
Страница 52: ...Page 52 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 Auto VI Wallbox Wiring ...
Страница 73: ...Page 73 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 SCC 40 Enclosure wiring for trips negative ...
Страница 74: ...Page 74 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 SCC 40 Enclosure wiring for trips positive ...
Страница 76: ...Page 76 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 Standard Wallbox Internal wiring ...
Страница 77: ...Page 77 GUARDIAN SCC 40 Issue Auto VI V3 6t 07 12 00 Standard SCC 40 Drawing ...