1
1. Introduction to the Power Xpert® Release trip unit
PXR tRiP units foR PoweR Defense molDeD case ciRcuit bReakeRs
MN012007EN March 2019 www.eaton.com
1. Introduction to the Power Xpert
®
Release trip unit
The Power Xpert Release (PXR) trip unit has features and flexibility that allow configuration
for a wide variety of protection applications. Communication options support integration
into supervisory systems to monitor performance and, if desired, control the circuit breaker.
Advanced metering of current, voltage, energy and power allow monitoring of real-time
energy use.
The PXR trip unit is available in multiple models from 15 A (60 A frame) through 2500 A in
MCCBs. All PXR trip units share common features including configuration of their protective
functions, cause-of-trip information, built in secondary injection for testing and a USB port for
connection to configuration and monitoring software. Certain models include energy meter-
ing with 1% accuracy, network connectivity, multi-language display and advanced protection
features.
The PXR trip unit, with its current sensors and a trip actuator, is the subsystem of a circuit
breaker that provides a wide variety of protective functions. The PXR analyzes signals from
the current sensors; if current level and time delay settings are exceeded then the PXR will
trip the circuit breaker. The overload and short circuit tripping characteristics for a specific
circuit breaker are determined by the current rating and user selected protection settings.
Metering uses those same current sensors to monitor and record current. In models that
include voltage metering, a full set of power and energy data is available with 1% accuracy.
Additionally the PXR supports a waveform capture mechanism by which you can monitor
your systems currents and voltages.
The communication systems provide real-time status and data from the PXR for integration
with business information systems, control schemes or other systems used by service
personnel. The PXR trip units support several field-busses including ModbusRTU, ethernet
Modbus TCP and ProfibusDP. Ethernet communications also includes an advanced web-
interface for use with phone, tablet or PC browsers.
Certain models have a LCD display to make set-up and system monitoring possible from
the face of the MCCB. Other models have rotary switches to set the available protection
settings. Regardless of the interface on the PXR trip units, all aspects of the configuration
and performance are available using PXPM software.
This manual covers the Power Xpert Release family in the Power Defense line of molded
case circuit breakers. Instruction leaflets (IL) are provided with each circuit breaker that
covers the installation. Both this manual and circuit breaker instruction leaflets should be
consulted when applying the PXR trip unit. Please access www.eaton.com/powerdefense
for full details.
1.1 Protection settings overview
The following table shows an overview of protection functionality available in the PXR
family trip units in Power Defense circuit breakers. Detailed information for each trip unit
and circuit breaker are in Section 9: Available protection settings. Note that external control
voltage is not required for protection functionality.
