Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 6 Boiler temperature control 2017-09-29
If the control system’s response is too prompt so that significant overshoot or even
permanent oscillations occur, setting parameters Xp, Tn and Tv must be increased in
steps. A new readjustment should be made only after the control action resulting from
the previous readjustment is completed.
t
TBo
TBoSetpt
3132D11
1. Reduce Xp in steps of about 25 % of the previous value.
2. Increase Tv in steps of 2 to 5 seconds.
If this is not sufficient:
3. Increase Tn in steps of 10 to 20 seconds.
6.5.5 External boiler temperature control
The RMH760B delivers a DC 0…10 V signal as the boiler temperature setpoint for an
external boiler temperature controller.
Main menu > Commissioning > Settings > … or
Main menu > Settings > Boiler > Setp compensation boiler
Operating line
Range
Factory setting
Setpoint at 0 Volt
–150…50 °C
0 °C
Setpoint at 10 Volt
50…500 °C
100 °C
Limit value
0…140 °C
10 °C
Using setting parameters, the DC 0…10 V output can be matched to the receiver’s
input. In the case of setpoints below the limit value, the output indicates DC 0 V.
6.6 Protective boiler functions
Main menu > Commissioning > Settings > … or
Main menu > Settings > Boiler > Limitations
Operating line
Range
Factory setting
Boiler temperature max
25…140 °C
95 °C
Boiler temperature min
8…140 °C
10 °C
Optimization min boiler temp
On / Off
On
Boiler return temperature min
---- / 8…140 °C
---- °C
Bypass pump switching diff
1…20 K
6 K
Lock sig maintained boil ret temp
None / Uncritical / Critical
Critical
Frost prot (release input off)
0…60 min
6 min
Frost prot (release input Off)
On / Off
On
Frost prot (release input off)
On / Off
Off
Protective boiler startup
On / Off
On
Protective boiler startup
Pump on / Pump off
Pump on
Delta boiler temp max (stage 2)
0…10 K
1 K
Control action is
too fast
Setpoint compensation
Settings