Square D LA26300 Molded Case Circuit Breaker
- 300A
- 2 Pole
- I-Line
Square D
LA26300
Molded Case Circuit Breaker
Brand
Square D
SKU
LA26300
Quantity
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Square D LA26300 - 300A 2 Pole Molded Case Circuit Breaker
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300A 2 Pole Molded Case Circuit Breaker
300A 2 Pole Molded Case Circuit Breaker
Description
Engineered for commercial power distribution, the Square D LA26300 is a 2-pole, 300A molded case circuit breaker. It features a thermal-magnetic trip unit with long-time and instantaneous (LI) functions. It installs into Square D I-Line panelboards and switchboards. As a legacy L-Frame device, it replaces older installations but is superseded by the PowerPacT LJA36300U31X for upgrades. Rated 42kA at 240VAC, it includes an adjustable magnetic trip, Visi-Trip indicator, and HACR certification.Specifications
| Brand | Square D |
|---|---|
| Part Number | LA26300 |
| Series | LA |
| Amperage | 300A |
| Poles | 2 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 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, Undervoltage Release, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Product FAQs
6 answersWhat type of panelboards accept the Square D LA26300?
The LA26300 features an I-Line style plug-in connection and is exclusively designed for use with Square D I-Line panelboards and switchboards. It is not compatible with standard QO, NQ, or NF series panels.
What wire sizes and materials are supported by the LA26300 lugs?
The standard lugs accommodate either a single conductor from 1 AWG to 600 kcmil or dual conductors from 1 AWG to 250 kcmil. Both aluminum and copper (Al/Cu) wiring are supported.
How does the trip adjustability work on the LA26300?
This breaker utilizes a thermal-magnetic trip mechanism with a fixed thermal element for continuous overload protection and an adjustable magnetic element, allowing electricians to fine-tune the instantaneous short-circuit response.
What is the modern replacement for the legacy LA26300 breaker?
The LA26300 is part of Square D's legacy L-Frame series. For modern upgrades or new installations requiring the same footprint and amperage, Schneider Electric has replaced this line with the PowerPact L-Frame series.
Does the LA26300 require line-side wiring during installation?
No. Because it utilizes an I-Line plug-in mounting style, the line side of the breaker features a jaw arrangement that connects directly to the panelboard bus. Wiring is only required on the load-side lugs.
Can the LA26300 I-Line breaker be reverse fed?
No. Breakers with I-Line plug-in connections feature a factory-configured jaw arrangement designed to mount directly to the energized panelboard bus. Because of this directional design, they cannot be reverse fed.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 13 reviews.
Total 5 star reviews: 13 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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Rating
13 reviews
- RGRobert G.Verified BuyerReviewingSquare D LA36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/16/26LA36400
Perfectly boxed and arrived on time. Thanks for the shirt and stickers as well.
- CECraig E.Verified BuyerReviewingEaton / Cutler-Hammer LA3600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars10/13/25Westinghouse breaker
Excellent customer service and quick shipping
- CLClifton L.Verified BuyerReviewingSquare D LA36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/30/25estimator
Good
- BCBenjamin C.Verified BuyerReviewingEaton / Cutler-Hammer LA3225 - 225A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/4/25Refurbished Breaker
Breaker seems to be working great, no complaints from Client
- JMJerry M.ReviewingEaton / Cutler-Hammer LA3400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/14/23Where is my breaker?
Where is my breaker?