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4. Complementary features
Power XPert® release triP unit for MagnuM PXr circuit breakers
MN013015EN January 2022 www.eaton.com
4.5 Auxiliary control power
Providing auxiliary control power to the PXR trip unit will
provide full functionality even when the circuit breaker is
open or when the circuit breaker is under very light load
such that the self-powering current transformer cannot
provide energy to power the trip unit. The relays and
communication channels require auxiliary control power for
operation. Auxiliary control power is connected to the circuit
breaker’s secondary terminal block. We recommend an
isolated supply such as the Eaton PSG family, 24 Vdc 0.5 A
is required.
Figure 17. Control power supply.
Remember: auxiliary control power is not required to provide
current protection features. Protection is active well before
any overload. The trip unit begins to power-up at very low
levels of current (approximately 40 A).
In situations where auxiliary control power may be intermit-
tent or sag during a transfer, an uninterruptable power supply
(UPS) is recommended to ensure continuous operation of
the relays and communication.
4.6 Secondary wiring terminals for Magnum PXR
Table 9 shows the circuit breaker secondary wiring terminals
by feature and terminal number. The name column refers
to the abbreviation used in this manual and on the terminal
label. The alternate name is sometimes seen on devices
which may be used within the larger system. Please refer to
MN013016EN which includes the secondary terminals wiring
diagram for additional circuit breaker wiring information,
including terminal numbers for installed accessories.
