Table of Contents
Advertisement
2. Waiting ... All primary modules conditions are
satisfied and module is counting down a delay
before acquiring primary ON status.
3. OFF by Sensor. System cooling or heating
temperature sensor failed.
4. OFF by no secondaries. Primary PLC communicates
with no secondaries.
a. Primary Status states 3 or 4 will cause all the
modules to run in Stand-alone mode. These
failing conditions are false at normal primary/
secondary operation.
b. Primary Online (Applies to secondary PLC only).
LED is green - secondary PLC is communicating
with primary PLC; LED is gray - secondary PLC is
not communicating with primary PLC.
Lead Module
Indicates which module is currently a Lead Module in
the chiller.
Evap / Cond Circuits
Displays Evaporator inlet and outlet temperatures and
an opening status of Evaporator Isolation Valves as
well as Ambient Temperature.
Control Temperature
Local module hot or chilled water temperature control
sensor.
Temperature Setpoint
Local module heating or cooling temperature control
setpoint. Can be adjusted by 'tech' user only.
Demand Compressors
Cooling or Heating Demand value in number of
requested compressors.
Temp Cntrl Settings
Viewable / adjustable for 'tech' user only.
•
Temp Diff +. Temperature control differential above
setpoint or positive dead band (DB).
•
Temp Diff -. Temperature control differential below
setpoint or negative DB.
•
Both of them define the temperature control DB.
•
Temp Stage-Up Delay. When next compressor has
been staged up, this delay has to elapse before next
compressor is allowed to stage up.
•
Temp Stage-Down Delay. When next compressor
has been staged down, this delay has to elapse
before next compressor is allowed to stage down.
On/Off Button
Used to turn secondary PLC module on / off in Stand-
alone Mode. For primary PLC module, On / Off Button
on the Home Screen serves the same purpose.
ARTC-SVX001B-EN
Overview Circuits
Refrigerant temperatures / pressures are displayed:
suction pressure; discharge pressure; suction
temperature; suction super heat temperature.
Liq Line Solenoid
Status of the solenoid valve installed on the liquid line
pipe.
EX Valve
Indicates the position of electronic expansion valve, if
installed.
Comp (X) En/Dis
Compressor enable / disable button.
Comp (X) Status
1. Comp OFF. Compressor is off and can't be turned
on.
2. Ready. Compressor is off but can be turned on.
3. OFF by Evap Flow. Compressor has been called to
run but waiting for Evaporator Flow proof.
4. OFF by Min Off. Compressor is cycling through
safety Minimum Off Time.
5. OFF by Switch. Compressor is off by En/Dis Switch.
6. OFF by Alarm. Compressor is off by Alarm.
7. Running. Compressor is running.
8. ON by Min On. Compressor has been called off
although it keeps running due to safety Minimum
On Time.
9. ON by Pumpdown. Compressor has been called off
but keeps running due to Pump-down sequence.
Comp (X) Speed
Can be displayed in different units.
1. Volts. If PLC analog output is used to control
variable speed compressor.
2. RPM. Compressor speed is communicated to
external variable speed drive, for instance VFD.
Module I/O Screens
Data is collected by sensors as either analog or digital
signals and displayed on the IO Status screens.
When the module screen is displayed, pressing the I/O
button displays the I/O menu.
The I/O menu is comprised of three screens. Both
primary and secondary modules have analog I/O
(analog input and analog output), and digital I/O (digital
input and digital output). The third screen, expansion I/
O, only applies to the primary module. For a dual Gen II
Air-Cooled chiller the expansion board applie to
secondary module.
O O p p e e r r a a t t i i n n g g P P r r o o c c e e d d u u r r e e s s
33
Advertisement
Table of Contents
