hager h3+, Инструкция по эксплуатации системы связи

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6LE005550A
Function of the Energy trip unit
3.2 Protection function
Fault example b):
- In the event of a fault downstream of circuit breaker Q2, only circuit
breakers Q1 and Q2 detect the fault. Thanks to the connection cable between
the circuit breakers, circuit breaker Q2 informs circuit breaker Q1 that it has
detected the fault. Circuit breaker Q1 then maintains its time delays whilst circuit
breaker Q2 inhibits its time delays to eliminate the fault instantly.
Setting the ZSI protection
The Energy P160 circuit breaker does not require any ZSI protection to be
configured. It is equipped with a ZSI output (ZSI2) to connect an upstream circuit
breaker. It is mainly designed to protect the feed circuit and does not allow receipt
of a ZSI signal from a downstream circuit breaker to be acknowledged.
The Energy P250 circuit breaker must activate the ZSI protection to acknowledge
selectivity per zone.
ZSI protection settings on P250
P250: ZSI setting
Short time delay protection ZSI ON-OFF (OFF by default)
Ground protection ZSI ON-OFF (OFF by default)
Note
It is important to ensure that ZSI protection on a P250 circuit breaker is kept
deactivated when not using the zone selective interlocking function. In fact, in this
case, setting the ZSI protection to ON will systematically reduce the trip time to an
almost instantaneous time ranging from between 20 and 80 ms.