Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Operating modes 03.10.2011
6 Operating modes
We differentiate between the room operating modes and plant operating modes.
Room operating modes refer to the desired climatic conditions in the room and are
operated by the end customer. The room operating mode is plant independent. It is
used for heating plants, refrigeration plant or for single or 2-speed ventilation
plants.
The plant is operated in a set plant operating mode to achieve the climatic
conditions in the room. The plant operating mode differs depending on the
application and requirement. It is directly influenced by the room operating mode.
6.1 Room and plant operating modes
There are 4 room operating modes and thus connecting multiple possible planting
operating modes. The table provides an overview of the plant operating modes
supported by the various room operating modes and basic types:
Room operating
mode
Possible plant operating mode For basic
type
A, U Comfort ( ):
 Normal operation (Comfort):
Plant operating permanently;
Control with comfort setpoint
 Demand operation
Switch on/off of the plant is demand
dependent; control to demand setpoint
when the plant is switched on
P, C
A, U
A
A
Precomfort ( ):
 Normal operation (Precomfort):
Energy saving operation for occupied or
empty room; plant in permanent
operation; control to Precomfort setpoint
 Sustained mode (Precomfort):
Demand compensated operation for an
occupied room; partially suspended plant
operation; Precomfort setpoint as switch-
on criterion
 Recirculated air operation (Precomfort):
Energy-saving operations for an
unoccupied room; plant operating
permanently at 100% recirculation;
Control with Precomfort setpoint
 Demand operation
Switch on/off of the plant is demand
dependent; control to demand setpoint
when the plant is switched on
P, C