Circuit Protection

Masterpact NW Circuit Breaker

Masterpact NW Circuit Breakers for Critical Power Applications

The Square D® Masterpact® NW DC power circuit breakers, the latest addition to the Masterpact product family, now offer a broad range of protection for DC systems. These ratings qualify the Masterpact NW breaker for use on critical DC power applications such as battery UPS systems, transit applications and DC backup systems in power plants and substations.

With the proven reliability and performance of the Masterpact family, the NW DC breakers are tested to meet UL 489 Supplement SC and IEC 60947-2 for DC circuit breakers.  

The latest generation of Masterpact NW breakers provides more options and flexibility to help you meet greater needs for circuit protection reliability. Using the latest in technology to provide higher interrupting ratings, smaller footprint and more accessories than any other insulated case breaker.  

Most OEMs in the data center market have either used or are aware of our Masterpact® circuit breakers. These breakers are the workhorses of the industry that are used in the most critical data center equipment such as generators, paralleling switchgear, UPS switchgear and switchboards. They are very attractive because of their low maintenance requirements, their wide range of short circuit protection, and electrically operated accessories.

Ideally suited for use with:

  • Power-Zone® 4 switchgear
  • Other switchgear and switchboard constructions requiring UL Listed circuit breakers
Data Center Application
  • Main service low voltage switchgear:  Power-Zone® 4 (PZ4), QED-6 and QED-2
  • Low voltage paralleling switchgear:  Power-Zone 4, QED-6 and QED-2
  • Low voltage load bank switchgear:  Power-Zone 4, QED-6 and QED-2
  • UPS input switchgear:  Power-Zone 4, QED-6 and QED-2
  • UPS output switchgear:  Power-Zone 4, QED-6 and QED-2
  • UPS static transfer switches
  • Generator main output breakers
NW ANSI

  • Complete product offering through 200kAIR without fuses
  • 800A to 5000A frames available
  • Rated for all AC voltage systems through 635V
  • ANSI short-time withstand ratings up to 100kA
  • Four racking positions: connected, test, disconnected, removed, with status indicator on cradle
  • Simple, visual contact wear indicators
  • Meets ANSI standard C37.13 and UL1066
  • Full complement of field installable devices
  • Selction of four interchangeable Micrologic® trip units with PowerLogic®  power metering, communications and monitoring capabilities available in advanced trip units
  • Most common relay functions as defined by ANSI C37.2 and C37.90 integrated into circuit breaker
  • Electrically operated (optional)
  • 4-pole breakers available
  • Mechanical and electrical operations test w/o maintenance
  • 800A to 1600A frame - 12,500 mechanical operations with 2800 electrical - ANSI value is 1750 (9700 total)
  • 2000A to 3200A frame - 10,000 mechanical operations with 1000 electrical - ANSI value is 250 (1100 total)
  • 4000A to 5000A frame - 5,000 mechanical operations with 1000 electrical - ANSI value is 250 (1100 total)
  • Arc flash limiting breakers available

NW UL489 breaker has most of the same features as listed for the Masterpact®:

  • Rated for AC Voltage systems through 600V
  • Available for mounting in fixed or drawout configurations
  • Available in constructions that meet ANSI C37.13 and UL1066 standards

Available to meet UL489, IEC 60947-2 and ANSI C37.13/UL1066. Ideally suited for use with:

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Spotlight:

A geartalk Presentation of the
MASTERPACT® NT Series Circuit Breaker

In this edition of geartalk, our Product Manager, Alan Kuntz, and Communications Manager, Dominique Duryea, discuss the MASTERPACT NT Power Circuit Breaker. Run length is 7.5 minutes.

The MASTERPACT NT Circuit Breaker is the latest addition to the MASTERPACT circuit breaker line. It is a fully tested, full-featured power circuit breaker in the smallest footprint available on the market today. Click here to view the MASTERPACT NT Webcast.

 Learn More:

Download the Masterpact NW Circuit Breakers handout.

Click here to go to the MASTERPACT NW Circuit Breaker product page.