Engineering Drawings
www.usa.siemens.com/hvaccomponents
Thermostats
A-49
Function Diagrams
RCU15U – Heating-Cooling
Key
T
Room temperature
Y1, Y2
Output percentage
W
Room temperature setpoint
Xdz
Dead band
XpH
Proportional band heating
XpK
Proportional band cooling
SDH
Switching differential for heating
SDC
Switching differential for cooling
2 P.
2-position outputs
RCU50U – Heating-Cooling with Minimum Limitation Cooling
Key
T
Room temperature
Y10
Output percentage
W
Room temperature setpoint
XpH
Proportional band heating
XpK
Proportional band cooling
VR
0 to 100% minimum limitation of
cooling output
c/o
Changeover
RCU50.2U – Heating-Cooling
Key
T
Room temperature
Y10
Output
percentage
W
Room temperature setpoint
XpH
Proportional band heating
XpK
Proportional band cooling
c/o
Changeover
Y1[%]
100
0
T [
∞
F]
100
Y2 [%]
Xdz
SDH
SDC
XpH
XpK
W
2 P
TH0904R1