Federal Pacific HJL634300 Molded Case Circuit Breaker
- 300A
- 3 Pole
- Bolt-On
Quantity
Federal Pacific HJL634300 - 300A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
A drop-in replacement for aging systems, the Federal Pacific HJL634300 is a 3-pole, 300A molded case circuit breaker built for commercial and industrial power distribution. This bolt-on MCCB installs into legacy Federal Pacific panels and switchboards. It serves as a substitute for the NJL634300 and replaces the HJL36300 (retrofit kit required), preventing costly panel upgrades. Rated 22kAIC at 600VAC, the H-Frame breaker features fixed thermal and adjustable magnetic trip functions.Specifications
| Brand | Federal Pacific |
|---|---|
| Part Number | HJL634300-R |
| Series | HJL |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 22kA @ 480VAC, 22kA @ 600VAC |
| Frame Type | HJL |
|---|---|
| Terminal Type | Lugs |
| For Use With | Federal Pacific Panels, Switchboards |
| Wire Gauge | 250-600 kcmil |
| Max Wire | 600 kcmil |
| Min Wire | 250 kcmil |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | UL 489 |
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | High Interrupting Capacity |
Product FAQs
6 answersWhat equipment is compatible with the HJL634300 circuit breaker?
This legacy H-frame breaker is specifically designed to fit Federal Pacific Electric (FPE) panels and switchboards engineered for bolt-on HJL-series breakers.
What wire sizes are supported by the standard lugs on this breaker?
The included lugs accommodate large conductors, accepting wire gauges ranging from 250 kcmil to 600 kcmil. Ensure your enclosure has adequate wire bending space for these larger conductors before installation.
How does the thermal-magnetic trip unit operate on the HJL634300?
This breaker features an LI (Long-Time, Instantaneous) trip function. The thermal element provides fixed overload protection, while the magnetic element is adjustable, allowing you to fine-tune the instantaneous short-circuit response based on your system coordination requirements.
Why is the HJL634300 considered a legacy breaker?
Federal Pacific Electric (FPE) ceased manufacturing operations decades ago. Original HJL frame breakers are sourced to maintain and service existing FPE switchboards without requiring a complete panel replacement or custom retrofit kit.
Does this breaker require specific mounting hardware?
As a bolt-on breaker, it mounts directly to the busbars of compatible FPE switchboards. You must use the appropriate busbar bolts and torque them to the original manufacturer specifications to ensure a secure, low-resistance connection.
What safety precautions apply when installing this legacy FPE breaker?
Installation should only be performed by a licensed electrician. Because this is a legacy component for older switchboards, always verify that the panel busbars are de-energized, clean, and free of pitting before bolting on the replacement breaker.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
- KLKari L.Verified BuyerReviewingSquare D HJL36040 - 40A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/9/26Great Customer Service
Working with Superbreakers the team is so helpful. They answer the phone and are very accommodating. We had an issue with the refurbished breaker not working out and they helped get a new one out right away.