Accessories
3.3 Control and signaling accessories
3WJ Air Circuit breakers
62 Operating Instructions, 12/2022, L1V30828903001-01
Undervoltage release (UVR/UVR-t)
The undervoltage release trips the circuit breaker if the control voltage US is unavailable or
drops to between 70% and 35% of its normal value (in compliance with the relevant
standard) and locks it to prevent reclosing until the auxiliary voltage is restored. The circuit
breaker can then be reclosed mechanically or electrically. The undervoltage release does not
need to be reset for this purpose.
The undervoltage release can be used for:
• Safe remote-controlled tripping
• Interlocking, to prevent closing
• Checking the voltage in the primary and secondary circuits
The undervoltage release is supplied with voltage via the secondary disconnect terminal
system.
It is available in two versions:
• Undervoltage release UVR:
Tripping occurs instantaneously or with a short-time delay, see section "Technical
specifications".
• Undervoltage release UVR-t:
Tripping occurs with an adjustable delay time from 0.2 to 3.2 s.
The circuit breaker with an undervoltage release can be closed at a control voltage from 85%
to 110% U
S
on the undervoltage release.
Shunt trip ST and the undervoltage releases are mounted in the same location
③. It is not
possible to use these accessories simultaneously.
The undervoltage release can be retrofit.
Technical specifications
The following tables show the technical specifications of the Closing coil (CC), Shunt trip (ST)
and Undervoltage releases (UVR/UVR-t).
To Next Page
Loading...
