SQUARE D NW30L Masterpact NW Air Circuit Breaker

Overview

The SQUARE D NW30L is a high-current air circuit breaker from the Schneider Masterpact NW series, branded under Square D. The SQUARE D NW30L is designed for main incoming, bus tie and generator feeder protection in low‑voltage power distribution systems. The SQUARE D NW30L supports electronic trip units with LSI / LSIG protection curves, power metering and fault event recording. It is widely stocked as spare switchgear component for industrial plants, commercial buildings, data centers and marine power panels. The SQUARE D NW30L is built for high breaking capacity and selective coordination within the electrical distribution network.

Features

The SQUARE D NW30L accepts interchangeable electronic trip units to match different protection requirements, including long time overload, short time delay, instantaneous and earth fault protection. The SQUARE D NW30L integrates built‑in current sensors for protection and electrical measurement, covering current, voltage, power, energy and harmonic monitoring. The SQUARE D NW30L supports optional communication modules for Modbus, Modbus TCP and IEC 61850 network connection, enabling remote monitoring and parameter adjustment. The SQUARE D NW30L is available in fixed and withdrawable versions, with mechanical interlock and electrical interlock functions to prevent misoperation. It is equipped with auxiliary contacts and alarm contacts for interlocking with PLC and SCADA systems, and complies with global IEC and UL standards for low‑voltage switchgear.

Specs

Device Type: Air circuit breaker Model: SQUARE D NW30L Series: Masterpact NW Frame Rating: 3000A frame Protection: Compatible with Micrologic electronic trip units (LSI / LSIG) Installation Type: Fixed or withdrawable Communication: Optional communication module Auxiliary Contacts: Standard auxiliary and alarm switch contacts Certification: IEC 60947‑2, UL 489 Protection Grade: IP30 for cabinet mounting Application: Main incoming switchboard, bus tie, generator feeder, data center power distribution, industrial and marine low‑voltage panel

Principle

The SQUARE D NW30L uses internal current transformers to sample three‑phase current signals and send data to the Micrologic trip unit. The trip unit compares measured values against preset protection thresholds. When overload, short‑circuit or earth fault occurs, the SQUARE D NW30L triggers the internal operating mechanism to open the main contacts and isolate the faulty circuit. Trip records and waveform data are stored for post‑fault analysis.

Applications

The SQUARE D NW30L is used for primary protection and energy monitoring of large‑capacity low‑voltage distribution systems in factories, power plants, data centers and offshore power facilities. The SQUARE D NW30L applies to spare stock and emergency replacement of existing Masterpact NW switchgear assemblies. It also supports switchgear renovation, protection coordination and communication networking projects.