DEMA CPM 310 G User Manual page 82

The tripping settings (shown within the red borders on
the picture in the middle) determine the tripping
behavior of the circuit breaker within the auto-reclosing
cycles, if a function (e.g. tI>) generates a trip decision.
The line under the title describes cycle numbers and
the line at the bottom comprises the settings. If any of
the setting values on the bottom lines is set as "1",
tripping by the related function at the related cycle will
be allowed; but if it is set as "0", tripping will be
prohibited. Note that the informative "S" abbreviation
stands for the standard tripping action that triggers the
auto-recloser and cannot be set as "0". According to
the sample settings on the picture, any tripping
decision generated by tI> function will result in tripping
on any cycles. Note that if a tripping option is set to "0"
and no other function clears the related fault when
occurred, the "0" option will be ignored at that time to
provide clearance of the fault. This algorithm ensures
prevention of failures of system protection due to auto-
recloser configurations.
The auto-recloser settings (shown within the yellow
borders on the picture to the left) determine the closing
behavior of the circuit breaker if a tripping because of
the related function (e.g. tI>) has occurred. According
to the sample settings on the picture being examined
here; no reclosing shots will be conducted if I>
protection function causes a time-delay trip, because
auto-reclosing options for all cycles are set to "0".
To have Auto-Recloser function into service, it is
required that,
1. One of the any programmable inputs is cabled to a
normally open auxiliary contact of CBs and 52a
appointment is done to that input,
2. One of the any programmable outputs is cabled to
the closing release terminal of CBs and Close CB
appointment is done to that output.
If the ARCL function is tried to be had into service
without fulfilling the requirements explained above, the
Alarm LED warns the user and the Alarm Menu displays
the following message: "Auto-recloser settings error". If
no corrective actions are taken, the auto-recloser
remains out of service. When the auto-recloser
functions are activated, any active latch settings are
automatically driven out of service; the reason is that
the auto-recloser cannot operate properly when there
are active latch functions that need manual resetting.
Knowing this, having any active latch settings manually
out of service is highly recommended to prevent
potential misinterpretations that the output relays that
are configured to latch under described conditions will
operate as set. It must always be kept in mind that the
Auto-Recloser settings overrule the latch settings. □
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