At mode 2 out of 4 the phase current setting, IP> can be checked by single-phase
injection where the return current is connected to the summated current input. The
value of residual (earth fault) current IN set lower than IP> is easiest checked in back-
up trip mode 1 out of 4.
6.3.7.1 Checking the phase current operate value,
IP>
Check the current level IP> where setting FunctionMode=Current and setting
BuTripMode=1 out of 3 or 2 out of 4 as set under Main menu/Settings/IED
Settings/Current/CCRBRF(50BF)/1:CCRBRF.
1. Apply the fault condition, including START of CCRBRF, with a current
below set IP>.
2. Repeat the fault condition and increase the current in steps until a trip occurs.
3. Compare the result with the set IP>.
4. Disconnect AC and START input signals.
Note! If NoI>check or Retrip off is set, only back-up trip can
be used to check set IP>.
6.3.7.2 Checking the residual (earth fault) current operate value
IN>
set
below
IP>
Check the low set IN> current where setting FunctionMode = Current and setting
BuTripMode = 1 out of 4 as set under Main menu/Settings/IED Settings/Current/
CCRBRF(50BF)/1:CCRBRF.
1. Apply the fault condition, including START of CCRBRF, with a current just
below set IN>Pickup_N.
2. Repeat the fault condition and increase the current in steps until trip appears.
3. Compare the result with the set IN>.
4. Disconnect AC and START input signals.
6.3.7.3 Checking the re-trip and back-up times
The check of the set times can be made in connection with the check of operate
values above.
Choose the applicable function and trip mode, such as FunctionMode = Current
and setting RetripMode = No CBPos. Check as set under Main menu/Settings/
IED Settings/Current/CCRBRF(50BF)/1:CCRBRF.
Section 6 1MRK 511 248-UEN -
Testing functionality
50
Commissioning Manual