CE1P2522E / 30.03.2000
Basic Documentation RVL470
Siemens Building Technologies
52/68
Function block "Contact H2"
Landis & Staefa Division
14. Function block "Contact H2"
On this function block, it is entered on which plant section the heat demand of contact
H2 acts.
14.1. Operating line
Line
Function, parameter
Unit
Factory
setting
Range
184
Function when terminals H2–M are linked
0
0 / 1
14.2. Description
Flow / boiler temperature control can be overridden by using remote operation. This is
accomplished by bridging terminals H2–M.
On operating line 184 – with plant types 1, 2 and 3 – it is possible to select to whom the
heat demand signal shall be passed:
Setting 0 = heat demand signal to the heat source
Setting 1 = heat demand signal to the heating circuit
With plant types 4 and 5, the heat demand signal is always passed to the ehat source.
On operating line 185, it is possible to select the setpoint to be used when H2–M is
connected:
0 = constant flow / boiler temperature setpoint, the RVL470 maintains that fixed value
1 = minimum flow / boiler temperature setpoint; the minimum temperature maintained by
the RVL470 is this setpoint, even if other demands call for a lower setpoint.
The setpoint can be adjusted on operating line 186.
As long as this function is active, the LED of the respective operating mode button
flashes at a high frequency (approx. 2 Hz).
When contact H1 is closed, contact H2 is inactive, which means that contact H1 has
priority over contact H2.
