User Manual

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Siemens RCU50... Room Thermostat CE1N3045en
Building Technologies 2017-11-15
Use
Control of the room temperature in individual rooms of ventilation or air conditioning
plants that are heated or cooled. The RCU50... are especially suited for use with VAV
systems in connection with VAV compact controllers type GLB181.1E / 3 and
GDB181.1E / 3.
The devices can also be used as an AHU temperature controller in connection with
valve actuators, as well as for universal heating and cooling applications with
DC 0...10 V actuators.
For the control of the following pieces of equipment:
∂ VAV compact controllers
∂ Valve actuators
∂ Air damper actuators
Functions
The room thermostat acquires the room temperature with its integrated sensor and
maintains the setpoint by delivering DC 0...10 V control commands. The RCU50...
provides P-control. With the RCU50 and RCU50.1, the proportional band can be 1 or 4
Kelvin in heating mode and 0.5 or 2 Kelvin in cooling mode (selectable with DIP switch
no. 4). With the RCU50.2, the proportional band is fixed, 4 Kelvin in heating mode and
2 Kelvin in cooling mode.
T [癈 ]
XpK
XpH
W
Y10 [%]
Y10 [%]
100
0
100
3045D01
c/o
VR
T Room temperature
Y10 Output percentage
W Room temperature setpoint
XpH Proportional band heating
XpK Proportional band cooling
VR 0 – 100 % min. limitation of cooling
output
c/o Changeover
T [癈 ]
XpK
XpH
W
Y10 [%]
Y10 [%]
100
0
0
100
3045D02
c/o
T Room temperature
Y10 Output percentage
W Room temperature setpoint
XpH Proportional band heating
XpK Proportional band cooling
c/o Changeover
Using the potentiometer at the rear of the room thermostat, the cooling signal output
can be limited to a minimum value of between 0 and 100 %. This can be used to
ensure a minimum supply air volume. When used in connection with a VAV controller,
this setting must be taken into account.
With the RCU50.2, the output signal can be inverted with the help of DIP switch no. 1. If
set to ON, 0 V corresponds to 0 % travel and 10 V to 100 % travel. In position OFF,
0 V corresponds to 100 % travel and 10 V to 0 % travel.
Signal input B1-M is used for outside temperature compensation. Using a DC 0...10 V
signal, the setpoint can be shifted by +/- 12.5 Kelvin. The neutral position is at DC 5 V
and means no setpoint shift.
Function diagram
“Heating–cooling“
with min. limitation
cooling
RCU50 and RCU50.1
Function diagram
“Heating–cooling“
RCU50.2
Minimum limitation of
cooling signal
(RCU50 and RCU50.1)
Inversion of output
signal (RCU50.2)
Setpoint shifting
(RCU50 and RCU50.1)