Sterlco GP Series 20-60 HP Packaged Chillers - Manual (Page 16)

GP Series Portable Chillers Chapter 2: Functional Description 16 of 93
High Pressure Cutout
This electro-mechanical cutout device opens the compressor control circuit if the refrigeration
system compressor discharge pressure exceeds 575 psig.
The high-pressure cutout is a manual reset device typically mounted on the
compressor discharge line inside the mechanical cabinet. Call a refrigeration
service technician to analyze the problem and reset the control.
Typical GPAC-20
Low Pressure Cutout (no switch but done through the transducer)
There are two pressure transducers in the refrigeration piping – one on the suction line before
the compressor and one on the discharge line after the compressor. Within the program there
are four settings that warn and fault based on these two pressure transducers. The low suction
pressure warning and fault are calculated based on the Freeze Point value entered into the
controller. The low discharge warning is set for 200 psig (1,379 kPa), and the compressor
will fault at 180 psig (1,241 kPa). To prevent nuisance tripping there are delays built in to the
program.
Call a refrigeration service technician to analyze the problem to prevent
recurring low pressure faults.
High pressure cutout