Woodward HighPROtec MCDLV4, Руководство пользователя

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Protective Elements
Commissioning: Overcurrent Protection, directional [67]
Object to be tested
For each directional overcurrent element is to be measured: the total tripping time (recommendation) 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 happen easily and
these are then detected safely. By measuring the total tripping time, it can be
ensured 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
time. The tripping delay should be specified by the customer. The total tripping
time is measured at the position signaling contacts of the CBs (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 switching times from the technical data, specified in the
relevant documentation, provided by the CB manufacturer.
Necessary means
Synchronizable current and voltage sources
May be: ampere meters
Timer
Procedure
Synchronize the 3-phase current and voltage sources with each other. Then simulate the tripping directions to be
tested by the angle between current and voltage.
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. Check then 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 trip delay
(measured 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.
703 MCDLV4 DOK-HB-MCDLV4-2E