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Valve outputs | Channel-independent functions
command value is interpreted as "0%" and an "ON" command value as
"100%". In the case of "Switching (1-byte) with command value limiting value",
the actuator evaluates the converted switching output signal in the same way
("OFF" is interpreted as "0%", "ON" is interpreted as "100%").
With some functions and events, valve outputs, which are configured to the
command value data formats "Switching (1-bit)" and "Switching (1-byte) with
command value limiting value", are always activated via a constant command
value through pulse width modulation (PWM), providing that command values
not equal to 0% or 100% are to be set (after bus voltage return, after an ETS
programming operation, during manual operation, with an active forced posi-
tion and with active emergency operation). PWM keeps being executed until
the named functions have been exited or, after the named events, no more
lower-level functions are active and a new command value telegram is re-
ceived via the bus, overriding the constant command value on the valve out-
put.
In this case, the constant command value set by the PWM is also included in
the pump control.
After bus voltage return and an ETS programming operation, the actuator al-
ways first transmits the status "Pump OFF" without a delay. The actuator then
updates the status to "Pump ON", providing that the condition for this has been
fulfilled and an optionally configured "Pump delay ACTIVE" has elapsed.
A valve output affected by a short-circuit / overload (valve completely closed
on deenergised closed or completely opened on deenergised opened) does
not influence the pump control.
Image 6: Pump control with sample command value characteristic
Optionally, the actuator can evaluate an external pump control signal (e.g. from an-
other heating actuator). This allows the cascading of multiple actuators with pump
control. The local heating actuator links the 1-bit telegram value of the "Pump control
- External" object with the internal state of the pump logically as OR and outputs the
result of this link via the "Switch pump" object. The telegram polarity of the external
object is fixed: "0" = Pump OFF, "1" = Pump ON.
Heating actuator 6-gang with controller | Order no. 2139 00 | 21393100
Page 45 of 257
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