Eaton The Power Xpert Release trip unit

System overview

Power Xpert Release® (PXR) trip unit has features and flexibility that allow

configuration for a wide variety of protection applications. The PXR is

available in multiple models for the Magnum PXR and Power Defense

SB (PD-SB) circuit breaker family. The models range from simple current

protection devices through more complex protection, metering, and

communication functionality. Communication options support integration

into a variety of systems to monitor performance. Advanced metering of

currents, voltages, power, and energy allows evaluation of real time

energy use.

The PXR trip unit, along with sensors and a trip actuator, provides the

protective function. The PXR analyzes signals from the sensors; if current

level and time delay settings are exceeded then the PXR trip unit will send

a signal and trip the circuit breaker. The automatic overload and short

circuit tripping characteristics for a specific circuit breaker are determined

by the current rating and user selected protection settings.

The internal current sensors consist of two coils; as current begins to flow

through the circuit breaker, the iron core coil generates the energy which

powers the trip unit. At the same time, the air core coil provides signals

which are processed to determine the magnitude of current the breaker

is carrying. Auxiliary control power is not required for current protection

functions.

The mechanical action required to initiate tripping of the circuit breaker

is provided by a trip actuator, an integral part of the circuit breaker

mechanism, which also includes a charging lever and mechanical trip

button. The trip actuator is automatically reset by the mechanism.

The master connection diagrams show how certain functions of the

trip unit are connected to external circuits. All wiring is landed on the

secondary connection

system directly above the circuit breaker. See Section 8 - Documentation

Cross Reference for the low voltage power circuit breakers user manual

and other related documents.

The PXR trip units are listed by Underwriters Laboratories Inc. (UL) for

use in Magnum PXR and PD-SB circuit breakers.

Power Xpert Protection Manager (PXPM) the windows based software

for the PXR trip units provides cost savings and advanced functionality.

This intuitive user interface allows for simple trip unit configuration,

testing, and real time reporting of operating conditions, including

current, voltage, power, and energy. The software also provides waveform

captures, post event logs, as well as the ability to check critical health

performance metrics.

Each PXR trip unit has embedded secondary injection and testing features

which run using PXPM software on your personal computer when

connected via a USB cable.

These unique features offer savings through labor reduction and avoid the

need for expensive proprietary testing kits.

PXPM’s extensive reporting features allow saving configuration files and

generating reports in PDF format for sharing as well as off-line configuration

files for use in restoring or replicating trip unit configuration. Refer to

Section 5 - Power Xpert Protection Manager software for details.

Power Distribution Monitoring and Control provides a user-friendly interface

for interaction with multiple PXR trip units, legacy trip units, meters, starters,

and drives.

Installed in your switchboards, switchgear, and motor control centers, it is

the engine that produces the user interface. You can view the screens locally

using an HMI mounted in or near the switchgear or remotely by using a

standard web browser.

The Power Distribution Monitoring and Control Enhanced features allow you

to safely monitor and operate the Magnum circuit breaker with PXR trip units,

as well as enable Arc Flash Reduction Maintenance System™ (ARMS or

Maintenance Mode) remotely, increasing safety for all personnel.