Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Fan speed controller, demand-controlled (basic type P) 03.10.2011
23.2 Demand-controlled speed control with
pressure setpoint optimization
The individual room controllers send their applicable damper position (0-100%) to
the primary air handling unit. With 0% = damper closed; 100% = damper open.
The signal does not correspond to the output signal from the individual room
controller to the volume flow controller. The damper positions are collected and
evaluated and used to optimize the duct pressure setpoints.
Plant level:
Bus signal level:
3150s58
The fan speed is optimized to open the air dampers controlled by the volume flow
controller as wide as possible. So that the volume flow controller or rooms always
have sufficient air without the need for the volume flow controller to reduce
pressure.
23.3 Set pressure setpoint compensation by
damper position
Demand signals from the individual VAV room controller directly control the primary
air handling unit. The VAV controller sends is damper position signals to the plant.
The plant reacts dynamically to the damper position and optimizes the duct
pressure setpoint accordingly.
The following types of pressure setpoint optimization are available:
 Supply air: Pressure setpoint for supply air based on the VAV damper position
for supply air. See application example 1
 Supply-extract air in parallel: Pressure setpoint for supply/extract air based on
the VAV damper position. Common use of the control signal. See application
example 2
 Supply and extract air: Pressure setpoint for supply/extract air fan based on the
VAV damper position together with the KNX volume flow controller supply and
extract air. Separate use of the supply and extract control signal. See application
example 3.
Note
Function principle