KMB NOVAR-1 Series, Operating Manual

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Novar 1xxx KMB systems
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4.3 Faulty Section Indication and Disablement
In the alarm setting (parameter 30) you can choose alarm indication or actuation from detecting a
faulty section (section error).
If at least one of these functions has been set, the controller continually checks reactive power
changes in the power system during the control process as the sections are connected and
disconnected and compares them with each section’s power recorded. If connecting and
disconnecting a section does not repeatedly result in adequate change to reactive power in the power
system (or a change to reactive power measured is very different from the capacitor’s value recorded),
the controller tags such a section as faulty and, if relevant alarm actuation has been set, it will disable
the section and stop using it in further compensation temporarily.
Alarm indication can be used for section disablement indication (see description of parameter 30). If
alarm actuation is not set, the controller will only tag the faulty section, trigger alarm indication, but will
keep using the section in compensation. A particular faulty section can be identified by
fast flashing
(about three times a second) decimal point in the section value display in the side branch of parameter
25 (as opposed to slowly flashing decimal point identifying not-yet-precise section – see description in
chapter above).
A section that has been temporarily disabled is periodically, about every five days, checked by
including it in compensation for one switching operation. If the controller detects a relevant response
in the power system (within adequate allowance) to connecting the section, it will include the section in
the control process again and, if the automatic section power recognition process is enabled, it will run
accurization process for it too. This way, for example, a repaired section is automatically included in
compensation (after replacing section fuse, for instance).
If the controller does not put a disabled section back to compensation automatically, such reinclusion
in the control process will take place in the following situations:
•
power supply interruption or controller initialization (see description further below)
•
editing the section’s value or one of parameters 21 through 23 (switching program,
smallest capacitor value, number of capacitors).
•
automatic section power recognition process
Faulty section indication and disablement can only be set for capacitive sections – choke sections, if
present, are not checked.
4.4 Compensation by Choke
The instrument allows connecting chokes for power system decompensation. The decompensation
system can be built as combined, in which case both chokes and capacitors are connected to the
controller, or only chokes are connected. In such cases, power of the minimum capacitor or the
minimum choke, whichever is less, is considered to be the C/k
MIN
value which determines sensitivity of
the power factor control.
It is recommended that decompensation chokes to be connected to outputs 5 and higher. Outputs 1
through 4 are reserved for capacitive sections, since the controller uses these outputs in the automatic
connection configuration detection process. Nevertheless, even the outputs 1 through 4 can be used
for chokes – but the automatic detection process cannot be used and parameter 16 must be set
manually in such case.
The automatic section power recognition process can also be used to determine values of the chokes
connected, but the compensation by choke limit power factor (parameter 27) must be specified at