Liebert iCOM Microprocessor TM-10098 - Manual (Page 38)

iCOM
Control Training and Service Manual
The Startup and Freeze Protection Program
The sequence for the call for cooling with the program features is as follows:
The need for cooling is defined by the control setting for the temperature setpoint,
proportional band, and deadband (if used). At this point the Winter Start Kit (WSK)
time delay is the wait period for the compressor to run without the indication of the
low-pressure condition (also known as LP bypass). The WSK time delay is
programmable with a range of 0 - 5 minutes. If the LP switch setting is achieved in
this time then full cooling is in process with the Freeze Protection (FP) now
watching the LP for an additional 10 minutes (fixed). If the LP remains closed the
cooling process continues.
If the WSK is not made in the set time period the cooling process stops and waits
an additional 5 minutes with the compressor off (no pumpdown). The liquid line
solenoid valve will remain open during this time period. If the LP switch is made
the control will now advance and wait for the freeze protection time delay as stated
as above. If the LP switch does not prove in the WSK time delay period plus the 5
minute wait period, the compressor is locked off and the Low Suction Pressure
Alarm will activate. A power off/ on reset is required to reset the cooling function.
If the WSK is made and the control is in the 10 minute Freeze Protection (FP) wait
time period and this function does not prove the LP the control will go into
additional 10 minute wait (fixed), with the compressor off (no pumpdown) and the
liquid line solenoid valve to remain open. If the freeze protection does not make
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