Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 9 Heating circuit control 2017-09-29
Here, the plant user can select the required operating mode. In mode, the
setpoint is determined either by the time program or the plant user. If desired, one of
the continuous modes (Comfort, Precomfort, Economy or Protection) with a fixed
setpoint can be selected.
In Protection mode, the heating system shuts down, but safety-related functions, such
as frost protection, will stay active.
The display shows the heating circuit’s setpoint that is currently maintained.
Different reasons can have led to the current state. Decisive is the control priority (refer
to subsection 9.3.7 "Control priorities in the heating circuit").
In preselected room operating mode
, the time switch changes the room
operating mode or the room temperature setpoint in accordance with the program
entered. During holidays, a fixed preselected setpoint is used:
Main menu > Heating circuit 1 (or 2 or 3) > Room operating mode
Operating line
Range
Factory setting
Room operating mode holidays
Economy / Protection
Economy
The holiday function is only active in room operating mode .
9.3.2 User request in the room
The plant user has several choices to override the current 24-hour program and to switch
to some other setpoint. Following can be used to override operation from the room:
• Switch or button (directly connected)
• KNX operator units (e.g. QAW740)
• Bus operator unit RMZ792
On the QAW740 room unit, the plant user can select the room operating mode via the
mode button (preselection of operating mode) or the timer button.
User interventions can also take place via a 3rd-party device with KNX interface (S-
Mode). Precondition is that preselection of the room operating mode is set to
.
In room operating mode
, the presence button can be used to change the room
operating mode for the period of time until the next switching point of the time switch is
reached. Changeover takes place between Comfort or Precomfort and Economy.
The timer function is identical with the timer function triggered via a conventional
button. For this reason, the setting used for the duration is also the same. The mode of
operation of this function is described in subsection 9.3.4 "Timer function".
External switches or buttons for overriding the room operating mode can be connected
to inputs "Room operating mode" and "Timer function". The mode of operation of these
inputs is described in the 2 following subsections.
They override the other control interventions in accordance with the control priority.
For a description of the control priorities, refer to subsection 9.3.7 "Control priorities in the
heating circuit".
Preselection
Room operation selector
⇒
State
Cause
Time switch
Operating mode
during holidays
Note
Overriding the
24-hour program
Room unit QAW740
3rd
-party devices
with KNX interface
Presence button
Timer function
Conventional switches
and buttons