User Manual

Siemens Building Technologies CE1N2821E / 29.11.1998
Landis & Staefa Division 5/8
The connection terminals are of the clamping type.
The control and heating cost allocation valve has a ready connected 7-wire cable of
1 m. It establishes the electrical connection to the conduit box.
Conduit box ALW30
p
WRV81.200 WRV81.400 WRV81.750
WRV81.1500
1000
100
10
1
0,07 0,1
0,5
11,52
V
2821D02
Pressure drop curves (measurement range position 2)
∆p Pressure drop in mbar
Flow rate in m
3
/h
The valve size should be selected such that the design flow represents 50 to 100 % of
the nominal flow rate.
The local regulations for heat metering and electrical installations must be observed.
The operating voltage of AC 24 V is supplied by an isolating transformer which powers
the whole SYNERGYR system and which must be installed near the central unit. When
sizing the transformer, the power consumption of all units connected to the building bus
must be taken into consideration.
The secondary side of the transformer may not be earthed.
Since the WRV81... operates with a variable measurement range, the pressure drop
across the valve should never exceed
0.12 bar
(WRV81.1500: 0.15 bar).
The surplus pressure must be reduced by a throttle mounted upstream of the WRV81....
Sizing
Engineering
notes
General
Control and heating cost
allocation valve