Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Preheating function (basic types A, P) 03.10.2011
Place the outside air sensor before the outside air damper.
T
3
1
4
0
Z
1
5
If the outside temperature is not available, the function can still be activated. In that
case, the function is activated for maximum purge time each time the plant is
started. This can be useful when the heating systems remains switched off in
summer (heating may not switch on demand-dependent via communication!).
If the plant is switched on shortly after switching off, the heating coils need not be
prepurged. The period of time after switching off where the preheating function
need not be activated can be set by using setting value "Locking time".
18.3 Troubleshooting
If the outside temperature is not available, the preheating function becomes active
for the maximum purge time each time the plant is started. In that case, the
positioning signal is 100%.
Example