Eaton NZMB1-4-A40 Molded Case Circuit Breaker - 25 kAIC 440V
Part Number: NZMB1-4-A40
Quick Summary
Eaton NZMB1-4-A40 Molded Case Circuit Breaker provides reliable distribution protection for industrial power panels. Engineers often struggle to find devices that fit tight spaces, trip quickly enough to prevent damage, and install quickly without rewiring, and this unit is designed to address those challenges with a compact footprint and front-frame mounting. The product lists compliances as 'Contact Manufacturer,' so confirm CE/IEC/UL certifications with Eaton for your region and application. Key performance specs include a 40 A rating, 440 V operating voltage, and a robust 25 kAIC short–circuit capacity, all in a four-pole NZMB1 frame that supports scalable, modular protection. This combination delivers safer panels, reduced maintenance, and clearer lifecycle costs for industrial facilities.
Product Information
Extended Description
NZMB1-4-A40 Eaton: Eaton Series NZM complete molded case circuit breaker, NZM1-frame, NZMB1, Thermal-magnetic trip type, 320-400A trip rating, Four-pole, 40A, 440 Vac, 25 kAIC, Distribution circuit protection, Rocker lever, 32-40A, Front frame clamp, 32-40A
Product Name
Eaton Series NZM complete molded case circuit breaker
Catalog Number
NZMB1-4-A40
EAN
4015082657994
Product Length/Depth
2.68 in
Product Height
5.71 in
Product Width
3.54 in
Product Weight
3 lb
Warranty
Eaton Selling Policy 25-000, one (1) year from the date of installation of the Product or eighteen (18) months from the date of shipment of the Product, whichever occurs first.
Compliances
Contact Manufacturer
Amperage Rating
40 A
Voltage rating
440 Vac
Trip Type
T268
Circuit breaker type
NZMB1
Frame
NZM1
Class
Distribution circuit protection
Accessories
Rocker lever
Setting Range Ol Protector
32-40A
Short-circuit breaking capacity
25 kAIC
Interrupt rating
25 kAIC
Connection
Front frame clamp
Overload range
32-40A
Number of poles
Four-pole
Trip rating
320-400 A
Feature 1: 40 A rating at 440 V in a four-pole design ensures balanced protection across three-phase feeders. Business impact: prevents overload damage and reduces nuisance trips, enabling stable production lines and less unplanned downtime. Application: distribution panels in manufacturing and processing facilities where precise overload protection is required. Feature 2: 25 kAIC short-circuit capacity provides a generous fault-current margin, safeguarding upstream equipment and wiring from severe arcing. Business impact: enhances system resilience and lowers risk of equipment damage during faults. Application: energised feeders in high-current environments such as motors and drives. Feature 3: Thermal-magnetic trip (T268) delivers fast yet selective tripping, improving reliability and maintenance intervals. Business impact: minimizes unnecessary outages while preserving protection where needed. Application: critical panel sections with mixed-load profiles. Feature 4: Front-frame clamp connection and rocker lever simplify installation and operation, reducing commissioning time. Business impact: faster panel retrofits and easier field testing. Application: dense switchgear enclosures and modular panel assemblies. Feature 5: Overload setting range of 32-40 A provides adjustable protection without replacing the unit. Business impact: tailor protection to evolving loads, reducing spare part requirements. Application: scalable protection schemes within NZM1 family panels. Feature 6: NZMB1 frame compatibility supports modular expansion with other NZM1 components. Business impact: enables scalable protection architecture, lowering total cost of ownership. Application: multi-cabinet installations requiring uniform protection devices.
Get a Quick Quote for a Eaton NZMB1-4-A40
Chat with us on WhatsApp - fast responses guaranteed
Need to speak with someone? We'll call you back within 2 hours during business hours
Interested in Eaton NZMB1-4-A40?
Enquire Now
FAQs
Yes. The NZMB1-4-A40 is built around the NZM1 frame and NZMB1 family, featuring a front-frame clamp and rocker lever for quick mounting and operation. It integrates smoothly with NZM1 accessories and other protective devices to form a cohesive modular protection scheme. For retrofit projects, verify the panel cutouts and mounting clearances to ensure clean assembly and service access.
Key specs include a 40 A continuous amperage rating, 440 V operating voltage, and a short-circuit breaking capacity of 25 kAIC. The trip type is thermal-magnetic (T268) with a setting range of 32-40 A and four poles. These parameters determine performance in 3-phase feeders and guide coordination with upstream breakers and fuses.
This breaker uses a front-frame clamp and a rocker lever, which simplifies mounting and manual operation in tight spaces. Dimensionally it measures 2.68 in depth x 5.71 in height x 3.54 in width and weighs 3 lb, enabling a compact footprint for dense panel layouts. Ensure proper clearance for fingers and wiring, and verify panel bus bars and lugs align with the front-frame connection.
Ideal for distribution circuit protection in 3-phase power panels and panelboards, especially where compact form factor, reliable overload protection, and high fault-current capability are required. It supports scalable protection schemes within NZM1-based architectures, making it suitable for motor feeders, process lines, and essential automation panels in manufacturing and industrial facilities.
Warranty terms follow Eaton’s policy: one year from installation or eighteen months from shipment, whichever occurs first. For regional compliance and certification documentation, contact Eaton to confirm CE/IEC/UL listings. Eaton support can assist with replacement parts, spare inventories, and guidance on lifecycle management for modular NZM1 panel protections.