Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 9 Heating circuit control 2017-09-29
Setting
Effect
[Curvepoint 1] return temp =
[Curvepoint 2] return temp
Constant return temperature limitation. The
outside temperature is of no importance
[Curvepoint 1] outside temp =
[Curvepoint 2] outside temp
Return temperature limit value, changes abruptly
at the curvepoints
[Curvepoint 1] return temp = --- Constant return temperature limitation with [curve-
point 2] maximum return temperature limit value.
The outside temperature is of no importance.
[Curvepoint 2] return temp = --- Constant return temperature limitation with [curve-
point 1] maximum return temperature limit value.
The outside temperature is of no importance
[Curvepoint 1] return temp and
[Curvepoint 2] return temp = ---
Return temperature limitation is deactivated
If the return temperature exceeds the limit value, the primary controller’s flow
temperature setpoint will be lowered. If the return temperature drops below the limit
value, the reduction of the flow temperature setpoint will be negated again.
Limitation works as an I-controller whose integral action time can be adjusted.
Main menu > Commissioning > Settings > … or
Main menu > Settings > Heating circuit 1 (or 2 or 3) > Mixing circuit controller
Operating line
Range
Factory setting
[Tn] return temp limitation max 0…60 min 30 min
9.8.3 Minimum limitation of the return temperature
Using the boiler return temperature sensor, it is possible to implement a common
minimum limitation of the return temperature for all consumers (heating circuits and
DHW heating) with no need for configuring a boiler. If the boiler return temperature
drops below the adjusted minimum limit value, the amount of heat drawn by the
consumers will be restricted by locking signals.
3133S99
For more detailed information about the configuration, refer to subsection 6.6.2
"Minimum limitation of the boiler temperature".
For information about the parameterization of this function, refer to subsection 6.6.1
"Maintained boiler return temperature".
9.8.4 Frost functions and general protective functions
It can be selected whether or not frost protection for the plant shall act on the heating
circuit pump.
The flow temperature is monitored for minimum limitation. If the flow temperature falls
below 5 °C, a heat demand signal is sent to the heat source and the mixing valve will
open. The function will be stopped as soon as the flow temperature has risen to 7 °C.
The function is active for a minimum of 5 minutes.
Frost protection for the
plant
Frost protection for
the flow