Switching Differential Of Room Temperature (Sdr) - Siemens RVA63.280 Basic Documentation

Benefits
Description
Setting
Effect
Note
Room temperature
control
Switching differential
Siemens Building Technologies
Landis & Staefa Division
2.25 Switching differential of room temperature
(SDR)
Temperature control with pump heating circuits.
Prevents overtemperatures in the rooms in the case of a pump heating circuit.
Serves as a room temperature limitation with pump heating circuits
Setting range
– . – / 0.5...4.0
The switching differential for two-position control will be changed.
Entry:
– . – Switching differential is inactive
• The pump always remains activated
Decrease: Switching differential will become smaller
• Pumps are switched on and off more often
• Room temperature varies within a narrower band
Increase: Switching differential will become greater
• Pumps are switched on and off less often
• Room temperature varies within a wider band
The room temperature sensor must be active
• This function only acts in automatic mode
• The display will show "ECO"
With pump heating circuits, the amount of heat supplied is controlled by switching the
pumps on and off. This is accomplished with 2-position control by means of the room
temperature's switching differential.
Functioning:
°C
ON
P
OFF
Pump ON TRw
Pump OFF TRw =TRw + SDR
ON
OFF
w
Basic Dokumentation RVA63.280, RVA53.280
Unit
°C
TRx
TRw+SDR
TRw
t
°C
Factory setting
– . –
Legend
TRx Actual value of the room
temperature
TRw Room temperature setpoint
SDR Switching differential of
room temperature
P Pump
ON Switch-on point
OFF Switch-off point
t Time
TRx Actual value of room
temperature
TRw Room temperature setpoint
SDR Switching differential of
room temperature
w Setpoint
102 Switching differential of
room temperature
Switch-on point
Switch-off point
CE1P2374E
19.04.2001
85/184