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ABB XT5NU340ABYN000XXX Molded Case Circuit Breaker

  • 400A
  • 3 Pole
  • Unit Mount
ABB XT5NU340ABYN000XXX
Molded Case Circuit Breaker
Brand ABB
SKU XT5NU340ABYN000XXX
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  • 400A
  • 3 Pole
  • Unit Mount

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ABB XT5NU340ABYN000XXX - 400A 3 Pole Molded Case Circuit Breaker

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$4,995.00 In Stock

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Description

Delivering reliable power distribution, the ABB XT5NU340ABYN000XXX is a 3-pole, 400A molded case circuit breaker from the SACE Tmax XT5 family. Built for ReliaGear neXT panelboards, switchboards, and motor control centers, this unit mount MCCB includes line side panel connectors and load side lugs. It replaces the legacy T5N400BW breaker. Featuring an adjustable thermal-magnetic trip unit (LI), it offers a 35kAIC rating at 480VAC. The breaker is HACR rated and supports reverse feed.

Specifications

Key specifications
Brand ABB
Series XT5
Amperage 400A
Poles 3
Mounting Style Unit Mount
Voltage 240VAC, 480VAC, 600Y/347VAC, 600VDC
Phase 3
AIC Rating 65kA @ 240VAC, 35kA @ 480VAC, 18kA @ 600Y/347VAC, 16kA @ 600VDC
Electrical ratings
Amperage Range 280-400A
Fit and installation
Terminal Type Lugs
For Use With ReliaGear neXT Panelboards, Switchboards, Motor Control Centers
Wire Gauge 2x 2/0 AWG - 500 kcmil (Cu/Al)
Max Wire 500 kcmil
Min Wire 2/0 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Adjustable Thermal, Adjustable Magnetic
Standards and features
Available Options Auxiliary Switch, Shunt Trip, Undervoltage Release, Motor Operator, Handle Lock
Accessories Line Side Panel Connectors, Load Side Lugs Included
Standards CSA C22.2 No. 5, IEC 60947-2, UL 489
Approval CCC, CSA, cULus, IEC, UL
Temp Rating -25C to 70C
Construction Features HACR Rated, Reverse Feed

Product FAQs

8 answers
What wire size is accepted by the standard lugs on the XT5NU340ABYN000XXX?

The included lugs are designed to accept two conductors per phase, accommodating wire sizes from 2/0 AWG to 500 kcmil for both copper and aluminum conductors.

What equipment is the XT5NU340ABYN000XXX designed to integrate with?

This XT5 frame breaker is engineered for use in ABB and GE ReliaGear neXT panelboards, switchboards, and motor control centers. Proper mounting hardware is required for panelboard integration.

How is the trip unit configured on this specific XT5 breaker?

It utilizes a TMA (Thermal Magnetic Adjustable) trip unit. This allows electricians to independently adjust both the long-time thermal response for overloads and the instantaneous magnetic response for short circuits.

What does the N signify in the XT5NU340ABYN000XXX part number?

The N designates the interrupting capacity tier within the ABB SACE Tmax XT family. For the XT5 frame, the Normal tier provides a 35kA rating at 480VAC.

Can this Tmax XT5 breaker replace legacy GE Spectra RMS breakers?

The ABB Tmax XT series is the official replacement for the discontinued GE Spectra RMS line. However, the XT5 is not a direct physical drop-in for legacy SG frames and requires specific retrofit kits for existing enclosures.

Can the XT5NU340ABYN000XXX be mounted in any orientation?

Yes, ABB Tmax XT molded case circuit breakers can be installed in vertical, horizontal, or flat positions without derating or impacting the performance of the thermal magnetic trip unit.

Are internal accessories field-installable on the XT5 frame?

Yes, the SACE Tmax XT5 supports field-installable internal accessories such as shunt trips, undervoltage releases, and auxiliary contacts. These are installed in the dedicated accessory compartments on the front of the breaker.

Does this breaker provide ground fault protection?

No, the XT5NU340ABYN000XXX features an LI (Long-Time, Instantaneous) thermal magnetic trip unit. It does not include built-in equipment ground fault protection.

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