Woodward HighPROtec MCDLV4, Руководство пользователя

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Protective Elements
Commissioning: Overcurrent Protection, non-directional [50, 51]
Object to be tested
Signals to be measured for each current protection element, the threshold values, total tripping time
(recommended), or alternatively tripping delays and the fallback ratios; each time 3 x single-phase and 1 x
three-phase.
Especially in Holmgreen connections, wiring errors can easily happen, and
these are then detected safely. Measuring the total tripping time can ensure
that the secondary wiring is o.k. (from the terminal on, up to the trip coil of the
CB).
It is recommended to measure the total tripping time instead of the tripping
delay. The tripping delay should be specified by the customer. The total tripping
time is measured at the position signalling contact of the CB (not at the relay
output!).
Total tripping time = tripping delay (please refer to the tolerances of the
protection stages) + CB operating time (about 50 ms)
Please take the CB operating times from the technical data specified in the
relevant documentation provided by the CB manufacturer.
Necessary means
Current source
May be: ampere meters
Timer
Procedure
Testing the threshold values
(3 x single-phase and 1 x three-phase)
Each time feed a current which is about 3-5% above the threshold value for activation/tripping. Then check the
threshold values.
Testing the total tripping delay (recommendation)
Measure the total tripping times at the auxiliary contacts of the CB (CB tripping).
Testing the tripping delay
(measuring at the relay output)
Measure the tripping times at the relay output.
Testing the fallback ratio
Reduce the current to 97% below the trip value and check the fallback ratio.
Successful test result
The measured total tripping delays or individual tripping delays, threshold values and fallback ratios correspond with
those values, specified in the adjustment list. Permissible deviations/tolerances can be found under Technical Data.
702 MCDLV4 DOK-HB-MCDLV4-2E