Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Operating modes 03.10.2011
The following table provides an overview of the primary setpoints to switch on/off
in dependence of the corresponding plant operating modes:
Plant operating mode
Controller 1 Controller 2, 3 IAQ controller
Sustained mode
(
Precomfort)
Precomfort cooling setp
Precomfort heating setp
Upper setpoint
Precomfort
Lower setpoint
Precomfort
Precomfort
Indoor air quality
setpoint
Recirculated air mode
(
Precomfort)
- - Switch recirculated air
mode to normal mode
(Comfort): Precomfort
Indoor air quality
setpoint
Sustained mode (
Economy)
Economy cooling setp
Economy heating setp
Upper setpoint Economy
Lower setpoint Economy
Economy-
Indoor air quality
setpoint
IAQ controller: The better signal always wins at simultaneous control of the mixed
air damper by controller 1 and IAQ controller.
As a result, the outside air damper can be opened to 100% even at low outside
temperatures. This applies to all plant operating modes.
If the heating coil output at outside temperature design conditions (e.g. -10 °C) is
not sufficient for 100% outside air volume, the max damper position can be limited
continuously as a function of the outside air temperature (see section 10.5 "Mixed
air dam
per (basic types A, P)").
6.3 Effective fan speeds as a function of the
plant operating mode (basic type A)
Fan control by plant control depends on the present plant operating mode. As a
rule, the following fan speeds serve as the basis:
 Off/On for single-speed or controlled fans
 Off / Speed 1 / Speed 2 for 2-speed fans
The following table shows the various possibilities and combinations for single-
speed or continuously controlled fans:
Plant operating mode Fan control description
Normal operation
(
Comfort)
Permanent for speed 1
Normal operation
(
Precomfort)
Permanent for speed 1
Sustained mode
(
Precomfort)
Speed 1 as soon as a Precomfort switch-on criterion
is met
1)
Recirculated air mode
(
Precomfort)
Permanent for speed 1
1)
Sustained mode
(
Economy)
Speed 1 as soon as a Economy switch-on criterion is
met
1)
Night cooling
Speed 1 as soon as night cooling switch-on criteria
are met
Plant OFF
Permanent on Off
1)
You can indicate for the extract air fan if it is to be switched on in sustained or recirculated air mode
(see section 10.1.13 "Sustained/recirculated air mode (basic t
ype A)")
Note
Important