FANOX SIA-B Series User Manual Download

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4.8.1. Circuit Breaker opening and closing commands

The circuit breaker opening and closing commands are implemented. These commands can be
executed from the HMI commands menu or using the HMI’s specific keypad or from local or remote
communications. In order that the command related to the key can run, the menu must be in standby
mode.
To carry out commands from the remote communications (ModBus, IEC60870-5-103, IEC61850 or DNP
3.0) the relay must be in TELECONTROL mode. (see the telecontrol section).
For the commands to have an effect, they should be assigned to the corresponding outputs. The

“Open

circuit breaker

” and “Close circuit breaker” bits are assigned to their corresponding outputs in the

“CONTROL” status group in the status menu.

4.8.2. Counter to register the number of openings

The SIA-B relay is fitted with a counter that registers the number of times the circuit breaker opens.
This counter is associated with the

“Maximum number of openings” setting. When the number of

openings exceeds this preset value, the

“Maximum number of openings” status is activated, and its

corresponding event is generated.
This counter reading can be set to any value from within its range from the HMI or by communications.

4.8.3. Accumulated amps counter: I2t

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).

4.8.4. Maximum openings in a time window

As well as counting the number of times the circuit breaker opens, the SIA-B relay 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.