Commissioning P54x/EN CM/La4
MiCOM P543, P544, P545 & P546
CM) 10-49
CM
8.4.7.1 Phase A
Prepare a dynamic A phase to neutral fault, as detailed above. Ensure that the test set is
simulating Steps 1 and 2 as one continuous transition. Connect a timer to start when the
fault injection (Step 2) is applied, and to stop when the trip occurs. To verify correct output
contact mapping use the trip contacts that would be expected to trip the circuit breaker(s), as
shown in the table. For two breaker applications, stop the timer once CB1 and CB2 trip
contacts have both closed, monitored by connecting the contacts in series to stop the timer if
necessary.
Single breaker Two circuit breakers
Three Pole Tripping Any Trip Any Trip (CB1) and Any Trip (CB2)
Single Pole Tripping Trip A Trip A (CB1) and Trip A (CB2)
Apply the fault and record the phase A trip time. Switch OFF the ac supply and reset the
alarms.
8.4.7.2 Phase B
Re
configure to test a B phase fault. Repeat the test in 8.4.7.1, this time ensuring that the
brea
ker trip contacts relative to B phase operation close correctly. Record the phase B trip
time. Switch OFF the ac supply and reset the alarms.
8.4.7.3 Phase C
Rep
eat 8.4.7.2 for the C phase.
The average
of the recorded operating times for the three phases should typically be less
than 20 ms for 50 Hz, and less than 16.7 ms for 60 Hz when set for instantaneous operation,
as in Permissive schemes. Switch OFF the ac supply and reset the alarms.
For Blocking schemes, where a non-zero Delta Dly time delay is set, the expected
operating time is typically within +/- 5% of the delay setting plus the “instantaneous”
delay quoted above.
8.4.8 Delta directional comparison scheme testing
8.4.8.1 Signal send test for permissive schemes (POR/POTT only)
Firstly, recon
nect the test set so that the timer is no longer stopped by the Trip contact, but is
now stopped by the Signal Send contact (the contact that would normally be connected to
the pilot/signaling channel).
Repeat the forward fault injection, and record the signal send contact operating time. The
measured operating time should typically be less than 20 ms for 50 Hz, and less than
16.7 ms for 60 Hz applications. Switch OFF the ac supply and reset the alarms.
8.4.8.2 Signal send test for blocking schemes only
Config
ure the test set to inject a dynamic sequence of injection, as follows:
Step 1
: Simulate a healthy three-phase set of balanced voltages, each of
magnitude Vn. No load current should be simulated. The duration of
injection should be set to 1 second. Step 1 therefore mimics a healthy
unloaded line, prior to the application of a fault
Step 2
: Simulate a reverse fault on the A-phase. The A-phase voltage must be
simulated to drop by 3 times the [3314: V Rev] setting, i.e.:
Va = Vn - 3 x V Rev
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