Engineering manual - UniSAB III 1.10.8
001930 en 2021.06
47/346
Alarms and shutdowns
Note 10
A 0.0 setting disables alarm/shutdown monitoring.
Note 11a
300 sec. delay, regardless of when limits are exceeded.
Note 11b 600 sec. delay, regardless of when limits are exceeded.
Note 12
The compressor must have been above 5% capacity.
When below 5% capacity alarm/shutdown monitoring is disabled.
Note 13 Shutdown monitoring delayed 15 sec. after compressor start.
Note 14
60 sec. delay, regardless of when limits are exceeded.
Note 15
HPC, HPO and HPX compressors only.
Note 16 Shutdown monitoring delayed 20 sec. after compressor start.
Note 17
For VMY Mk 2-2.5, calculate the following: (see Fig. 6) Oil pressure = Oil pressure
3 (after oil filter) - Discharge pressure 2. For all other compressor types (except
SAB 80, see Note 20), calculate the following: Oil pressure = Oil pressure 3 (after
oil filter) - Suction pressure 1.
Note 18
The limits are not active until Ext. inp. s. has been selected in the menu Setup
/Configuration/External input.
Note 19
For SAB 80 the differential pressure across the oil filter is calculated as follows:
(see Fig. 6) Oil filter diff. pressure = Discharge pressure 2 - Oil pressure 4 (after oil
filter).
The stated oil filter pressure will thus be 0.1 to 0.7 bar higher than the actual pres-
sure loss across the filter due to the pressure loss across the oil separator and the
oil cooler.
The maximum allowed pressure drop across the oil filter is 1.2 bar. Consequently,
the alarm limit should be set between 0.8 and 1.4 bar or lower. The shutdown limit
should be set between 1.1 and 1.7 bar or lower.
Note 20
Set points 1 and 2 are used for shutdown monitoring of the mechanical oil pump,
see Engineering manual. For SAB 80, S50, S70 and S93 the oil pressure is calcu-
lated as follows: (see Fig. 6) Oil pressure = Oil pressure 3 (after pump) - Suction
pressure 1.
For SAB 80, S50, S70 and S93 the differential pressure across the oil pump is cal-
culated as follows: (see Fig. 6) Oil pump pressure = Oil pressure 3 (after pump) –
Oil pressure 4 (before pump).
Note 21 The set points are only used if the compressor is equipped with an electrical oil
pump. The set points are used to control the oil pump. When the differential pres-
sure (discharge pressure - suction pressure) falls below set point 1, the oil pump
will start. When the differential pressure exceeds set point 2 for 60 seconds, the oil
pump will stop.
Note 22
The set points are used to control the full flow pump. When the pressure falls be-
low set point 1, the full flow pump will start. When the pressure exceeds set point 2
for 60 seconds, the full flow pump will stop.
Note 23 The set points are used for liquid slugging, alarm and shutdown. This alarm/shut-
down is released by a sudden decrease in discharge temperature which is greater
To Next Page
Loading...
Need help?
General
