West Control Solutions Pro-4 - Manual (Page 68)

7.4 Loop alarm
The loop alarm monitors the control loop for interruption
(not with three-point stepping controller and not with signallers.)
With parameter LP.AL switched to 1(= loop alarm active), an interruption of
the control loop is detected, unless the process value reacts accordingly with
Y=100% after elapse of 2xTi.
The loop alarm shows that the control loop is interrupted. You should check hea-
ting or cooling circuit, sensor, controller and motor actuator.
During self-tuning, the control loop is not monitored (loop alarm is not active).
7.5 Heating current input / heating current alarm
The heating current alarm monitors the heating current.
In addition to short circuit monitoring, checking either for overload (current >
heating current limit value) or for interruption (current < heating current limit va-
lue) is done.
Each of the analog inputs can be used as measurement input.
If electrical heating is concerned, INP2 which is always provided can be configu-
red for measuring range 0...50mA AC and connected directly using a heating cur-
rent transformer.
a
With t1 < 400 ms or tp < 200 ms (effective time!), heating current monitoring
is ineffective.
Special functions
Loop alarm 68 KS 90-1 / KS 92-1