Art. No. ..5192KRMTSD
Art. No. ..5194KRMTSD
4.2.4.3.9 Valve protection
Valve protection may be carried out periodically in order to prevent the addressed control valves
of the heater or cooling system from becoming calcified or stuck. When set to "Yes", the "Valve
protection" parameter in the "Room temperature control -> Controller functionality" parameter
node activates valve protection.
This type of protection is generally started not only for non-active command value outputs, i.e.
for outputs which have not requested any heating or cooling energy over the past 24 hours. For
these outputs, by taking into account the following parameterisation the controller will
periodically set the command value to the maximum value once a day for a duration of
approx. 5 minutes...
Command value output not inverted:
-> 1-bit command value: "1", 1-byte command value: "255"
Command value output inverted:
-> 1-bit command value: "0", 1-byte command value: "0"
Thus even long closed valves will be opened briefly on a regular basis.
i
A controller disable has no influence on the valve protection. This means that valve
protection is carried out, even when the controller is disabled.
i
The controller checks the 24 hr time cycle for valve protection using its internal clock. With
a time-synchronised clock, valve protection takes place each day at 8.00 in the morning. If
the time signal has not be synchronised via the bus for a long time, then the time is hidden
in the display. However, the clock continues to run internally with the deviation to be
expected. This means that the valve protection time may shift continually with an
unsynchronised clock.
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Software "Room controller display compact module 146x11"
Functional description
