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Building Technologies Division
Basic documentation LMV36...
CC1P7544en
Infrastructure & Citiies Sector
7 Basic unit
25.09.2013
7.3.6 Gas pressure switch-min (Pmin), start release gas X5–01
Input for connection of a pressure switch-min for gas: If the plant does not require a
pressure switch-min, a wire link must be fitted between pin 2 and 3.
Gas pressure switch-min
In all types of gas trains, minimum gas pressure is expected from phase 22. If no gas
pressure is detected when the maximum time (parameter 214) has elapsed, the gas
shortage program is started (refer to chapter
Gas shortage program
).
LMV...
Bild 366e/1010
X5
-0
1
Protective earth (PE)
Gas pressure switch-min (Pmin)
“L” for pressure switch
Figure 22: Gas pressure switch-min (Pmin) X5-01
Caution!
The OEM must check to see whether the burner can be operated without
pressure switch-min. This may necessitate a special approval, depending on
the
type of application.
No. Parameter
214
Max. time start release
285
Oil: Gas pressure switch-min with «Lo Gp»
0 = inactive
1 = active
During the safety times (TSA1/TSA2), the signal received 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
229
Gas: Time to respond to pressure faults within safety time 1 (TSA1) and safety
time 2 (TSA2)
329
Fuel 1 gas: Time to respond to pressure faults within safety time 1 (TSA1) and
safety time 2 (TSA2)
If there is no gas pressure, at least safety shutdown is initiated.
Error
code
Diagnostic
code
Meaning for the LMV36... system
20
0
Pressure switch-min (Pmin)
No minimum gas pressure
20
1
Gas shortage start prevention
23
0
Pressure switch-min (Pmin)
No minimum gas pressure
23
1
Gas shortage start prevention