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4. Complementary features
Power XPert® release triP unit for MagnuM PXr circuit breakers
MN013015EN January 2022 www.eaton.com
4. Complementary features
The PXR has features which allow you to integrate within a
larger system. An external neutral sensor can be added to
3-pole breakers. A control power supply will keep the trip
unit active when there is insufficient current in the phases
to self-power. Relays can be used for signaling conditions
within the breaker. Communications can be used to monitor
real time operation. Testing functionality eliminates the
need for separate secondary injection equipment. The event
capture information is extremely valuable in investigating the
cause of an alarm or trip. Finally, the health monitoring func-
tions allow you to understand the impact of each event and
guide you in servicing the Magnum PXR circuit breaker.
4.1 Neutral sensors
In a 3-pole breaker, an external neutral sensor is connected
to the secondaries at N1 & N2. See Section 4.6 - Secondary
wiring terminals for Magnum PXR for terminal number-
ing. The proper polarity of the sensor and conductor, both
marked on the sensor, is important. The external sensor
may be selected as Rogowski or iron-core CT (factory
default) based on your application requirements. The system
does not harvest energy to power-up the trip unit from the
external neutral sensor.
Figure 14. External neutral sensors.
If neutral sensing is not needed in your application, select
the iron-core CT setting or jumper N1 to N2.
Table 7. External neutral sensor part numbers.
Magnum
PXr frame
neutral
sensor type
instruction
leaflet
sensor
eaton Pn
Narrow and
standard
Rogowski
(bus bar)
IL0131154EN
NRMPN
70C2183G04
Iron-core CT
(window)
MSCNCT
9253C03H17
If the sensor installed does not match the selection in the
trip unit, the reading will not represent the actual current
flowing in the neutral. Apply a primary current through the
sensor to verify. A mismatch will result in either a much
higher or lower (10x or more) reading than actual. Change
the setting to match the sensor and re-check.
4.2 Configurable relays
The PXR contains three relays which can be configured to
indicate various conditions within the circuit breaker. They
have factory default configuration depending on style to indi-
cate relay #1 = Maintenance Mode Active or Health Warning,
relay #2 = High Load Alarm or Ground Fault Alarm, and relay
#3 = Breaker Trip (all current triggered trips).
The contacts of the relays are wired at the circuit breaker’s
secondary terminal block. Refer to Section 4.6 - Secondary
wiring terminals for Magnum PXR for terminal locations and
contact ratings.
The relays may be reconfigured using PXPM to the indicate
any of the following conditions. Note that up to two condi-
tions can be mapped to the same relay if desired.
Table 8. Configurable relay functions (continued).
condition/function
name
Description of relay operation:
the relay will close
when …
the relay will open
when …
Aux. contact
Breaker is closed
Breaker is open
Bell contact
Breaker is tripped
Breaker is not tripped
(open or closed)
High load 1 alarm
Current flow is greater
than setpoint (adjustable
from 50% to < high load
2 of I
r
)
Current flow falls 5%
below the setpoint
High load 2 alarm
(relay #2 default, non-GF
styles)
Current flow is greater
than setpoint (adjustable
from > high load 1 to
120% of I
r
)
Current flow falls 5%
below the setpoint
Maintenance mode
active
(relay #1 default ARMS
styles)
Trip unit is in the
maintenance mode
When the trip unit exits
Maintenance Mode
ZSI active
ZSI function active
ZSI is not active
ZSI input received
A ZSI INPUT signal is
received
RESET button is pressed
or communications reset
command received
ZSI output sent
A ZSI OUTPUT signal
is sent
RESET button is pressed
or communications reset
command received
High temperature alarm
Temperature exceeds
5°C (41°F) below the
level of the temperature
trip setting
Temperature falls 5°C
(41°F) below the trip
setting
Ground fault pre-alarm
Ground current is
greater than the setpoint
(adjustable from 50% to
100%)
Ground current falls 5%
below the setpoint
Thermal memory alarm
Thermal memory value
is >75%
Thermal memory value
is <70%
Watchdog alarm
Auxiliary power is active,
and the trip unit is
healthy and operating
There is an error in the
trip unit from any of the
self-diagnostics
Low battery alarm
Battery is below 1 bar
(25%)
Battery value is 1 bar
(25%) or higher
.
