ABB i-bus KNX Product Manual page 38

ABB i-bus KNX
© 2009 Busch-Jaeger Elektro GmbH – A Company of the ABB Group
Commissioning
PWM cycle is 0% up to control value
Options: - 0%
- 5 %
- ...
- 10 %
- ...
- 30 %
If the control value is very small for PWM control, the switch-on period
for the actuator might not be sufficient to put in motion the connected
thermoelectric valve gear. A valve drive opens or closes by warming
or cooling an expansion element. However, it always takes time for the
element to heat up or cool off sufficiently to allow the valve to be opened
or closed. As a result, the valve might not even open with very small control
values.
The parameter "PWM cycle is 0% up to control value" can be used to
prevent switching with control values that are too small. This parameter
allows you to configure the control value at which the actuator switches on.
This parameter is only available if the "Cooling" or "Heat and cool" control
functions are used and the cooling control type is set to "PWM".
PWM cycle is 100% up to control value
Options: - 70%
- 75 %
- ...
- 90 %
- ...
- 100 %
If the control value is very large for PWM control, the switch-off period
for the actuator might not be sufficient to put in motion the connected
thermoelectric valve gear. A valve drive opens or closes by warming
or cooling an expansion element. However, it always takes time for the
element to heat up or cool off sufficiently. As a result, the valve might
not even open with very large control values.
The parameter "PWM cycle is 100% up to an output value" can be used to
prevent switching with control values that are too large. This parameter
allows you to configure the control value at which the actuator switches on.
This parameter is only available if the "Cooling" or "Heat and cool" control
functions are used and the cooling control type is set to "PWM".
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