Johnson Controls SABROE Unisab III Control - 2.3. Shutdowns and alarms with identification numbers for screw compressors

P oil >
[1.5 x P suct ]
+ 1.1 bar
No
No
Low main oil
pressure alarm
Yes
ALARM
No
Yes
Allow load
Reset
t36 = 0
Unload
Yes
t36 > 3 min
C
P oil >
[1.5 x P suct ]
+ 1.0 bar
t36 + 1
Alarm off
B
Fig. 9: Insufficient main oil pressure during low differential pressure, SAB 157HR
C
D
P disch - P oil
> 2.7 bar
Yes
No
No
Yes
Low oil
pressure alarm
ALARM
T37 > 10 min.
reset
t37 = 0
Fig. 10: Oil circuit pressure drop
Note: For SAB 157HR the alarm limit is 1.7 bar.
Alarms and shutdowns
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Engineering manual - Unisab III 1.10
001930 en 2014.09