Square D LH26300AC Molded Case Circuit Breaker
- 300A
- 2 Pole
- I-Line
Quantity
Square D LH26300AC - 300A 2 Pole Molded Case Circuit Breaker
New
Quantity
Description
Built for heavy-duty industrial power distribution, this 300-amp I-Line molded case circuit breaker utilizes an AC phase connection configuration. The plug-on design mounts seamlessly into Square D I-Line panelboards and switchboards, reducing installation time on the factory floor. Delivering 65kAIC at 240VAC and 35kAIC at 480VAC, it includes push-to-trip functionality and adjustable magnetic settings for precise long-time and instantaneous protection.Specifications
| Brand | Square D |
|---|---|
| Series | LH |
| Amperage | 300A |
| Poles | 2 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 25kA @ 600VAC, 50kA @ 250VDC |
| Frame Type | L |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | (1) 1 AWG-600 kcmil (Al/Cu) or (2) 1 AWG-250 kcmil (Al/Cu) |
| Max Wire | 600 kcmil |
| Min Wire | 1 AWG |
| 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, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Lugs (AL400LA) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, HACR, IEC, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, High Interrupting Capacity, Push-To-Trip, Phase Connection AC |
Product FAQs
6 answersWhat does the "AC" suffix mean in the LH26300AC catalog number?
The "AC" suffix indicates the breaker is configured for an A-C phase connection on the I-Line bus. This determines which two phases of a three-phase panelboard the breaker will draw power from.
Which panelboards accept the LH26300AC circuit breaker?
This breaker is designed exclusively for Square D I-Line panelboards and switchboards. It features a plug-on I-Line connection on the line side and mechanical lugs on the load side.
What are the acceptable wire sizes for the LH26300AC load lugs?
The standard load lugs accept either one 1 AWG to 600 kcmil conductor or two 1 AWG to 250 kcmil conductors per phase. The lugs are rated for both copper and aluminum wire.
Is the Square D LH26300AC a current product line?
The LH series is a legacy L-frame molded case circuit breaker. For modern upgrades, Square D has replaced this series with the PowerPact L-frame family, which utilizes electronic trip units.
How does the trip unit on the LH26300AC operate?
It features a thermal-magnetic trip unit with a fixed thermal element for long-time overload protection and an adjustable magnetic element for instantaneous short-circuit protection.
Can the LH26300AC be used in DC power systems?
Yes, this breaker is rated for DC applications up to 250VDC, providing an interrupting rating of 50kAIC.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 2 reviews.
- MLMatthew L.Verified BuyerReviewingSquare D LH36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/21/26Super Breakers Does It Again!
New, in excellent condition, cheaper and faster than the competition
- MGMarkus G.Verified BuyerReviewingSquare D LH36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars11/4/25it states correctly what it was
Product as described