FANOX SIL-D00, User Manual

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4.7.3. Accumulated amps counter:
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An accumulated amps counter is also fitted. This counter accumulates the amps that are cleared
by the circuit breaker by opening.
When the circuit breaker opens, the maximum number of primary amps in any of the phases is
detected. This reading is squared and divided by 1000 and then rescaled to KA and
accumulated. If the current detected in the opening is less than the rated current, the rated
current value is used for the accumulation.
It is used in conjunction with the counter of the number of openings, to measure the circuit
breaker aging process.
Since primary amps are being accumulated, it is essential to correctly adjust the phase CT
transformation ratio.
The "Maximum accumulated amps" setting is associated with this counter. When the number of
accumulated amps exceeds this preset value, the "Maximum accumulated amps" status is
activated and its corresponding event is generated.
The value of this counter can be started at any value within its range from the hmi or from
communications, if this protection is fitted on a circuit breaker with a previous service life.
This alarm can be replaced by modifying the Accumulated Amps counter.
The display unit shall be KA² (square kilo amperes).
4.7.4. Maximum openings in a time window
As well as counting the number of times the circuit breaker opens, the SIL-D equipment sets up
a time window and the maximum number of openings allowed during this time. Both parameters
can be adjusted.
When this number is exceeded, the "Repeated Trips" status is activated and its corresponding
event is generated.
This alarm resets itself, when the corresponding time is exceeded with less trips than those
indicated.