DOC. MIE91093 Rev. 1.34 Page 78 of 145
times depends upon the programmed value for the reclaim
time TD:
.. If the programmed value is more than the recloser setting,
then the test set will generate N+1 faults, followed by N+1
fast Close commands (because they are all new faults);
.. If the programmed value is less than the recloser setting,
then the test set will generate N+1 faults, followed by N Close
commands of different delays (because they are all the same
fault), and there will be no Close command after fault N+1.
The reclaim time test, that is the test that the reclaim time is
correctly set, cannot be performed directly, because the
Recloser does not have an auxiliary output that trips as it
expires. For this reason, the reclaim time is tested with two
test sequences, as follows.
. First test: TD is programmed greater than the Recloser’s
reclaim time TDr, for instance TD = 1.05*TDr. Program the
number of tests N foreseen by the Recloser. As the fault
arrives after the reclaim time is expired, the Recloser must
always issue the close command, also after N+1 faults; there
is no evolution in the time delay. This behavior confirms that
faults occur after TDr has expired. The following time diagram
explains the test evolution.
The first fault starts the sequence. The relay trips after D1;
the Recloser sends a reclose command after R1. The test set
automatically injects fault No. 2 after the programmed TD,
that is more than TDr: the Recloser sends the reclose
command No. 2. If N = 1, the sequence is completed; else,
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