Schneider NW25 H1 ACB Air Circuit Breaker Unit

Module Feature

NW25 H1 belongs to Schneider Masterpact NW series draw-out air circuit breaker.

Frame current 2500A, H1 short-circuit breaking grade, Icu=65kA at 440V AC, rated working voltage up to 690V. It supports Micrologic 2.0/5.0/6.0 series trip controllers, providing overload, short-time delay, instantaneous short-circuit and earth fault protection. Drawer structure has connected, test and isolated three working positions, convenient for live inspection and maintenance without full cabinet power cut. It can be equipped with motor charging mechanism, shunt release, undervoltage release, anti-condensation heater and Modbus communication module, widely used for heavy industrial main power incoming, generator outlet and important feeder protection.

Working principle

When the loop current exceeds the protection setting value, the Micrologic trip unit sends trip signal to release mechanism.

The spring stored-energy mechanism drives main contacts to separate rapidly, and the arc chute extinguishes the electric arc to cut off the fault circuit. The drawer chassis mechanical interlock ensures safety during racking operation. The breaker uploads real-time electrical parameters and fault records to SCADA system through communication bus, and supports remote opening/closing control.

Onboard components

Main contact assembly, arc quenching chamber, spring energy storage operating mechanism, Micrologic trip controller, LCD display module, drawer base, motor charging assembly, shunt / undervoltage release coil, position auxiliary switch group, communication terminal block.

LED indicators

Front LEDs indicate spring charged, breaker closed, breaker open, pre-alarm warning and protection trip fault status.

Hardware self‑diagnosis

Built-in supervision detects current sensor unbalance, trip unit power loss, communication interruption and internal electronic abnormality. Fault codes and historical event logs can be checked on local LCD or uploaded to EcoStruxure Power commissioning software.

Programming software

EcoStruxure Power Commission software, used for protection curve coordination setting, fault log export, Modbus address configuration and breaker function debugging.

Electrical & Process Parameters

Model:NW25 H1 Brand:Schneider Electric Device type:Draw-out air circuit breaker Function:Main incoming and feeder fault protection for large low voltage power distribution system

Mechanical & Structure

Mounting:Draw-out chassis installation inside LV switchgear compartment Protection class:IP30 front panel Housing:Insulated reinforced frame with metal drawer chassis

Environmental

Operating temperature:-25℃ ~ +70℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing

Certification:CE, IEC 60947-2, UL

Status:Legacy Schneider low voltage distribution spare

Installation

Install matched drawer base in switchgear compartment and complete reliable grounding.

Push breaker to connected position after wiring inspection, set protection coordination parameters before power-on commissioning, verify test and isolation position interlock function.

Interface

Main L1/L2/L3 power contact set, auxiliary control terminal block, Modbus communication port, shunt / undervoltage release wiring terminals.

Diagnostic

Protection trip: Overload, short circuit or earth fault on downstream side, check trip record to confirm fault category.

Unable to rack in/out: Mechanical interlock locked, breaker not at open position or chassis foreign matter jamming.

Communication offline: Bus wiring loose, station address conflict or trip controller failure.

Product Brief

Schneider NW25 H1 air circuit breaker, Masterpact 2500A drawout ACB spare for industrial and power station main power distribution cabinet replacement.