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Siemens
Central control unit RMB795B
CE1P3122en
Building Technologies
Function block: "Room group"
18.01.2012
The maximum precooling/preheating period can be limited.
Main menu > Commissioning > Settings > …
or
Main menu > Settings > Room group 1..10> Optimum start control >
Operating line
Area
Factory setting
Forward shift on max
0...2880 min
360 min
All plant elements are switched in accordance with the next operating mode during
optimum start control.
8.7.3
Troubleshooting
Optimum start control is not executed without a reference room temperature.
8.8
Control functions for individual room
controllers
Manual control functions can preset various plant operating modes on individual
room controllers. The functions are only executed by the individual room controller
for a room group, however, only if the conditions on the individual room controller
so permit, e. g. emergency heating is only run if the room temperature drops below
the heating setpoint. The control function remains active until you manually reset it
to "Auto" on the RMB795B.
Main menu > Room group 1…10 > Room operating mode >
Operating line
Range
Factory setting
Preselection room grp
control
Auto, Heating, Boost heating,
Cooling, Night purge,
Precooling, Off, Test,
Emergency heating, Fan
only, Free cooling).
Auto
Response by the individual room controllers for the various control functions
depends on the connected type of device.
Control
function
Influence on RXB/RXL room controller
Influence on RDG/RDF/RDU room
thermostats
Auto
Heating or cooling.
Individual room controller automatically changes over between heating and cooling dependent
on the actual and setpoint temperature.
Heating
Heating only
Individual room controllers can only heat. The cooling sequences on the individual room
controllers are locked.
Note: This superposed control function is relevant to 4-pipe systems only. It does not impact the
H/C changeover in a 2-pipe system.
Boost
heating
Maximal heating
The room controller must be in Economy
operating mode. It heats as quickly as possible to
the Precomfort setpoint if the actual temperature
is below the setpoint. Objective: Preheat the
room in the event of heating.
Not supported
The room thermostat assumes the function
Heating
.
Setting values