Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 8 Main controller and primary controller 2017-09-29
8.5.3 Heat demand outputs
In addition, a digital output (relay) and / or analog output (DC 0…10 V) can be
configured on the main controller as a heat demand output.
For further information refer to sections 7.2 "Heat demand outputs" and 8.2
"Configuration".
8.5.4 Heat demand transformers
The heat demand transformers described in chapter 7 "Heat demand and heat
requests".
8.6 Mixing valve control
8.6.1 General
The heat output for mixing valve control can be reduced by functions of higher priority
(e.g. limitation of the return temperature) or by functions of other plants (boiler, DHW
heating) via load control.
The following mixing valve settings are valid for both 3-position and DC 0…10 V
actuators.
Main menu > Commissioning > Settings > … or
Main menu > Settings > Main controller > Mixing circuit controller
Main menu > Settings > Primary controller > Mixing circuit controller
Operating line
Range
Factory setting
Actuator run time
1…600 s
150 s
P-band Xp
1…100 K
50 K
Integral action time Tn
0…600 s
60 s
Locking signal gain
0…200 %
100%
• For more detailed information about mixing valve control and its settings, refer to
section 5.7 "Mixing valve control"
• Locking signal gain is used to preselect to what degree the primary controller shall
respond to signals received from load control
8.6.2 Load control
Load control signals from a heat source can have an impact on the primary controller:
A load reduction can be triggered by one of the following functions:
• Protective boiler startup
• Minimum limitation of the boiler return temperature
The primary controller does not respond to locking signals triggered by DHW heating.
From the consumer’s point of view, a load increase can be effected in the form of pump
and / or mixing valve overrun. In that case, the load is only maintained.
8.7 Setpoint increase
Typically, a mixing valve requires a setpoint increase, enabling it to compensate for
boiler temperature variations. With system pumps, this setpoint increase is not a basic
requirement for compensating boiler temperature variations. However, in the case of
Load control
Note
Load reduction
Load increase