Restriction Of The Modulation Range; End Of Running Position - Siemens LMV37.4 Series Basic Documentation

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9.4.6 Restriction of the modulation range

If the modulation range for stage 1 and stage 2, or stage 3, shall be further restricted, 2
parameters can be used to define a new low-fire and new high-fire position.
No. Parameter
Lower output limit
545
undefined = 20 %
Upper output limit
546
undefined = 100 %

9.5 End of running position

When there is no more heat request, the system switches to phase 62. Here, the burner
runs down to low-fire as long as possible before the valves are shut.
The available period of time can be set via parameter 212. If this period of time is set to
the minimum value, the burner is immediately shut down should the heat request disap-
pear. If the time exceeds 32 seconds, the burner always runs to the low-fire position.
Naturally, it is also possible to set intermediate times.
No. Parameter
212 Max. time down to low-fire
Basic documentation LMV37.4...
9 Electronic air-fuel ratio control
CC1P7546en
01.12.2009