Abelko IMSE WebMaster Pro - 6.4 Controlling three-state actuators

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6 - Controllers
6�3�5 Transducer
A transducer supplies the actual value to the controller. Two transducers can be connected to the
WMPro, and they can generate the actual value in three dierent ways: the sensor with the lowest
temperature, the highest temperature or the mean value of the two sensors. One of the transducers
can also be used for the minimum threshold. In a ground heating system, for example, the risk of
frost means you want to maintain a minimum temperature in the return. You can set the threshold
temperature using a parameter in the controller's "View" page.
6�4 Controlling three-state actuators
In this section we will congure a three-state actuator (increase, stop, decrease). You can use the
controller tool to do this.
Open Settings/Controllers
Select the Three-state actuator controller type and click New.
This opens the conguration page.
One of the actuators in the controller we congured earlier has a three-state actuator. Start by as-
signing a name. Choose the channel you want to use as the control signal. When we congured
the controller earlier, we specied an analog output for actuator 1. You can use this, in which case
the controller will have outputs for
both actuator types. If you select New
instead, there will be a channel called
Control signal 1 Radiator circuit.
Select any of these as the input signal.
Also select the digital outputs you
want to use for the Increase and De-
crease signals. You have the option of
selecting an alarm channel that sets
the Increase or Decrease channel to
On. This could be useful if the actua-
tor is controlling a valve with frost
protection. When the frost protection
is tripped, the Increase output will be
permanently On.
In this case, select the frost protection
alarm as the input signal for constant
Increase. If you select two alarms and
they are triggered simultaneously, the
alarm generating the Increase signal
has priority. The actuator in this exam-
ple has no special alarm function. The
outputs are pulse-width modulated,
and you can specify the period time.