Engineering manual - UniSAB III 1.10.8
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001930 en 2021.06
Set-up
At compressor start-up, this timer is used to delay the open/close function for the oil return valve draining
the oil separator.
See subsection 3.6.3 Oil return from oil separator (ChillPAC)
48. Pump down
For chiller use only.
This timer controls the maximum time the pump down sequence can run after compressor stop. Pump
down is used when the Chiller DX expansion valve control is configured.
This pump down function, where the compressor runs with a closed expansion valve, lets the compres-
sor run until the suction pressure is below the ”pump down set point” or until the pump down timer has
run out, whichever comes first.
49. PMS delay
After compressor stop it is possible to delay the PMS Start request output signal within the stated time.
This delay can e.g. be used for pump after-run.
50. Oil pressure low-low delay
For SMC reciprocating compressors.
The low-low oil pressure shutdown will be delayed for the stated time at compressor start.
57. Liquid level delay
For chiller use only.
The Liquid level delay timer is used for the Liquid level limiter as a hysteresis to prevent the compressor
from increasing the capacity immediately after the liquid level is back to normal. The compressor may in-
crease capacity when the timer has run out.