ABB RELION 620 Series Technical Manual page 757

1MRS757644 F
620 series
Technical Manual
input of another relay, or by routing the light signal output through the communication
to an input of another relay.
It is possible to block the tripping and the light signal output of the arc protection stage
with a binary input or a signal from another function block.
Cover unused inputs with dust caps.
Arc protection with one protection relay
In installations, with limited possibilities to realize signalling between protection
relays protecting incoming and outgoing feeders, or if only the protection relay for the
incoming feeder is to be exchanged, an arc protection with a lower protective level can
be achieved with one protection relay. An arc protection with one protection relay
only is realized by installing two arc lens sensors connected to the protection relay
protecting the incoming feeder to detect an arc on the busbar. In arc detection, the arc
protection stage trips the circuit breaker of the incoming feeder. The maximum
recommended installation distance between the two lens sensors in the busbar area is
six meters and the maximum distance from a lens sensor to the end of the busbar is
three meters.
A040362 V2 EN
Figure 382: Arc protection with one protection relay
Section 4
Protection functions
751