Designed for commercial and industrial electrical systems, this 175A molded case breaker delivers robust overcurrent protection. It mounts into legacy Federal Pacific panelboards, offering an exact fit for aging infrastructure without requiring adapters. Featuring a fixed thermal-magnetic trip unit, the three-pole device handles 18kAIC at 480VAC and 25kAIC at 240VAC. This N-Frame component ensures continued operation of existing distribution setups.
What panelboards are compatible with the NFJ437175 circuit breaker?
This N-Frame breaker is designed exclusively for legacy Federal Pacific panelboards. It features a standard bolt-on connection for direct installation into existing enclosures without the need for retrofit adapters.
Can the NFJ437175 be used in 480V commercial systems?
Yes, this breaker is rated for up to 480VAC with an interrupting capacity of 18kA, making it suitable for standard commercial branch circuit protection. It is also rated for 250VDC applications with a 10kA interrupting capacity.
How does the NFJ437175 connect to the panelboard and load?
The breaker utilizes a bolt-on mounting style to secure directly to the bus of legacy Federal Pacific panelboards. The load side features factory-installed lug terminals that accept 4 AWG to 300 kcmil wire.
What is the difference between the frame amperage and trip amperage on this breaker?
The NFJ437175 is built on a 225A N-Frame, which dictates the physical size and maximum capacity of the breaker housing. However, it is factory-equipped with a fixed 175A thermal-magnetic trip unit to protect the specific circuit.
Is the NFJ437175 still manufactured by Federal Pacific?
No, this is an obsolete legacy circuit breaker. It serves as an exact replacement component for maintaining aging Federal Pacific distribution systems that require a 175A, 3-pole configuration.
Can the trip settings on the NFJ437175 be adjusted in the field?
No, this breaker is equipped with fixed thermal and fixed magnetic trip elements. The long-time and instantaneous trip functions cannot be adjusted.
What type of overcurrent protection does the NFJ437175 provide?
It features a non-interchangeable, fixed thermal-magnetic trip unit that delivers long-time and instantaneous (LI) protection against overloads and short circuits.
SuperClub
Join free. Get 500 SuperPoints.
Earn points on eligible purchases and redeem them at checkout.
We source obsolete and hard-to-find parts every day.
Shipping
Free Shipping Policy
Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.
We strive to ship out your items the same day the order is placed. In rare circumstances SuperBreakers may reserve up to 5 business days to consolidate orders for complete shipment.
Expedited Shipments
Orders being shipped via Next Day Air, 2 Day Shipping or 3 Day Shipping must be received by 3 PM EST to guarantee same-day shipments. Expedited orders only ship on normal business days. Shipments will NOT be sent out on Saturdays and Sundays.
International Shipping
All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.
Reviews
Review summary
Customers rate this product 4.7 out of 5 based on 3 reviews.