Eaton PXR25V000L0AM Electronic Trip Unit

The PXR25V000L0AM is part of Eaton's PXR family of electronic trip units, specifically designed for NZM series molded case circuit breakers (MCCBs) with a 250A frame size. It provides comprehensive protection and monitoring for low-voltage power distribution systems, combining adjustable settings with optional communication capabilities.

Protection Functions

This trip unit offers LSI protection: Long-time overload (L), Short-time delay (S), and Instantaneous (I) functions. Long-time pickup is adjustable from 0.4 to 1.0 x In, with selectable time delays. Short-time protection includes adjustable pickup and delay, with I²t on/off. Instantaneous pickup is adjustable from 1.5 to 12 x In. All settings are made via rotary dials or DIP switches on the front, ensuring easy configuration without software.

Measurement and Accuracy

The PXR25V000L0AM continuously measures true RMS current in each phase, providing accurate overload protection even in the presence of harmonics. Trip accuracy is ±5% for long-time and ±10% for short-time and instantaneous functions. A LED indicator provides local trip indication. The unit is self-powered from the current sensors, requiring no external control power.

Communication and Monitoring

This variant (V000) does not include communication modules, but it is designed to accept plug-in communication modules (e.g., Modbus RTU, Profibus) for remote monitoring and control. When a communication module is installed, the trip unit can transmit current readings, trip status, and cause of trip, enabling integration with building management or SCADA systems.

Compatibility

The PXR25V000L0AM is compatible with Eaton NZM2, NZM3, and NZM4 MCCBs rated 250A. It mounts directly into the breaker, replacing thermal-magnetic trip units. The mechanical and electrical interfaces are standardized, allowing retrofit upgrades in existing installations.

Environmental and Standards

The trip unit operates in ambient temperatures from -25°C to +70°C and is humidity resistant. It complies with IEC 60947-2 (Annex F) and UL 489 requirements for electronic trip units. The enclosure provides IP40 protection when installed in the breaker.

Applications

Typical applications include main distribution boards, industrial switchgear, and critical power systems where precise protection and coordination are required. The LSI curve allows selectivity with downstream devices, minimizing downtime.