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Building Technologies   Basic documentation LMV37.4...  CC1P7546en 
  7 Basic unit LMV37.4  17.12.2018 
 
Oil pressure switch-min 
 
In all types of oil train, the minimum oil pressure is expected from phase 38. If no oil 
pressure is detected when the maximum time (parameter 217) has elapsed or if, 
subsequently, the oil pressure drops, the system initiates lockout. 
 
No. Parameter 
217 
Maximum wait time for detecting a detector signal or pressure switch signal 
(e.g. home run, preignition) 
 
Error 
code 
Diagnostic 
code 
Meaning for the LMV37.4 
20 0 
Pressure switch-min 
No min. gas / oil pressure 
20  1  Gas shortage start prevention 
 
During the safety times, the signal from pressure switch-min is only assessed after a 
certain period of time in order to ignore the pressure shocks that occur the moment the 
valves open. The time to elapse for signal assessment can be parameterized. 
 
No. Parameter 
269  Oil: Time to respond to pressure faults in the first and second safety time 
 
7.3.8  Setting the time for making the pressure switch test 
 
For oil pressure switch-min, the point in time after which the evaluation is made can be 
set via parameter 276 (active from phase 38 or from the safety time). 
 
No. Parameter 
276 
Oil: Input pressure switch-min 
1 = active from phase 38 
2 = active from safety time