Technical documentation
Rev. 02
Reactive Factor Controller CX plus
69
12.7 Detection of step power loss (Step Power Loss)
The CX plus shall detect the power loss of the individual steps and switch off and permanently lock the
affected steps in case the value falls below a limit value.
Solution:
The CX plus continuously adjusts the current step size to the determined value when switching a step
on and off. This function is also active when the step identification is switched off.
The alarm system of the CX plus compares the current step size of each individual step with the
original step size:
Step size in % of the initial value = current step size / original step size *100%
If the current step size fell below 75% of the original step size, the alarm system may trigger a step
alarm step power loss and switch off and permanently lock the affected steps.
The step alarm step power loss serves for the protection of the upstream throttle of the individual
capacitor steps. The capacitor and the upstream throttle form a filter (absorption circuit). This is
designed in a way that an odd harmonic is not completely absorbed. If the current step power has
already fallen below 75% and if it continues to fall, there is the risk that the absorption circuit
completely absorbs the odd harmonic. In this way, the throttle is overloaded and wiil finally be
destroyed.
Procedure:
Activate the function “Step alarm step power loss” (SETUP/516).
Set the setting to “
YES
” in the SETUP menu 516.
Function:
If the current step size of a step fell below 75% of the original step size, the step alarm step power loss
is triggered. The message
and the step number of the affected step are signalled
alternatingly on the display and the contact of the alarm relay is activated.
If several steps are affected, only the lowest step number of the affected steps is displayed.
The affected step is switched off immediately and set to the step type “FOFF”. The step is
locked for the control resp. manual operation. The step type of the affected step is blocked and
cannot be changed.
In order to reset the alarm and to activate the affected steps, the steps must be changed first. After
this, the step size must be entered manually (SETUP/402) for each affected step. The step size for
these steps may now be set back to
“
AUTO
”. The steps may be switched again by the control resp. in
manual operation.
If no step triggers the alarm anymore, the alarm is rese
t, provided that the function “Manual reset”
(SETUP/501 = NO) is deactivated. The alarm messages (display and alarm relay) are reset
automatically. The alarm relay is only reset, if no other alarm is active.
NOTE:
The monitoring of a step only works, if the step identification for this step is concluded or if the
step size was entered manually.
