Masterpact NW

Masterpact NW is a comprehensive range of air circuit breakers designed to protect electrical systems from damage caused by overloads, short circuits and equipment ground faults. Embedding Micrologic control units, it contributes to safety.


Masterpact NW circuit breakers are equipped with Micrologic control units that offer built-in power and energy metering in addition to basic or advanced protection functions. Two sizes are sufficient to cover applications from 800 to 6300 A, with breaking capacity from 42 to 150 kA.

The range comes with a wide choice of standardized accessories. The universal design of the Masterpact circuit breaker line allows most accessories to be used across the entire line. It enables standardization of electrical switchboards by providing peace of mind in terms of choice, installation, and operation.


  • Rated current: 800 to 6300 A

  • Breaking capacity: 42 to 150 kA at 220/415 V AC

  • Voltage rating: up to 1150 V AC

  • 2 physical sizes: 800 to 4000 A, and 4000 A to 6300 A

  • Draw out and fixed mount

  • 3-pole and 4-pole construction

  • Electronic Micrologic control units, integrating current, voltage, power and energy metering enabling energy management, earth leakage protection, and other advanced protection or network analysis functions

  • Switch disconnectors version available

  • Optimized range of field-installable auxiliaries and accessories

  • Different offers complying with different international standards: IEC 60947, UL489, ANSI/UL1066

  • CCC, EAC and other local certifications

  • Compliance with specifications of marine classification companies: Bureau Veritas, Lloyd's Register of Shipping, Det Norske Veritas, etc.

Micrologic control unit specifications:

  • 4 levels of protection against overloads and short circuits: 2.0 (LI), 5.0(LSI), 6.0(LSIG), 7.0 (LSIV, built-in earth leakage protection)

  • 4 types of measurement: A (Ammeter), E (Energy), P (Power), and H (Harmonics)

  • Energy reduction maintenance setting (ERMS) function available for arc flash protection for Micrologic P and Micrologic H

  • Measurement accuracy: Class 0.5 for voltage, Class 1.5 for current, and Class 2 for active power and energy

  • Compatible with both Ethernet and Modbus SL protocol

  • Operating assistance to diagnose tripping cause and maintenance information

Reviews For Masterpact NW

Add Your Review

Your Rating

First Name*

Last Name*


Your Review*