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Square D MAL36300 Molded Case Circuit Breaker
- 300A
- 3 Pole
- Unit Mount
Square D
MAL36300
Molded Case Circuit Breaker
Brand
Square D
SKU
MAL36300
Quantity
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Square D MAL36300 - 300A 3 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D MAL36300 - 300A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | MAL36300 |
| Series | MAL |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MAL |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D Switchboards, Motor Control Centers, Enclosures |
| Wire Gauge | (3) 3/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 3/0 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 |
|---|---|
| Accessories | Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Non-Interchangeable Trip |
Quantity
Square D MAL36300 - 300A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | MAL36300 |
| Series | MAL |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MAL |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D Switchboards, Motor Control Centers, Enclosures |
| Wire Gauge | (3) 3/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 3/0 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 |
|---|---|
| Accessories | Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Non-Interchangeable Trip |
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Description
Engineered for commercial and industrial applications, the Square D MAL36300 is a 3-pole, 300A molded case circuit breaker. It delivers reliable thermal-magnetic protection for heavy-duty electrical distribution systems. This unit mount breaker installs into Square D switchboards, motor control centers, and enclosures. As a legacy M-frame component, it is officially replaced by the newer MGL36300 model for modern upgrades. Rated at 30kAIC at 480VAC, it includes AL900MA lugs.Specifications
| Brand | Square D |
|---|---|
| Part Number | MAL36300 |
| Series | MAL |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MAL |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D Switchboards, Motor Control Centers, Enclosures |
| Wire Gauge | (3) 3/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 3/0 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 |
|---|---|
| Accessories | Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Non-Interchangeable Trip |
Product FAQs
5 answersIs the Square D MAL36300 still in production, or is there a direct replacement?
The MAL36300 is a legacy M-frame circuit breaker. For modern panel upgrades or replacements, it is superseded by the PowerPact M-frame series, specifically the MGL36300.
What is the adjustable magnetic trip range for the MAL36300?
The instantaneous magnetic trip on this 300A breaker can be adjusted from a low setting of 1500A to a high setting of 3000A.
What wire sizes are accepted by the standard lugs on this breaker?
The breaker uses AL900MA standard lugs, which accept three 3/0 AWG to 500 kcmil aluminum or copper conductors per phase.
What equipment is compatible with the MAL36300 breaker?
This unit mount breaker is designed for hardwired installation in Square D switchboards, motor control centers, and industrial enclosures. It is not compatible with I-Line plug-on panelboards.
What does the LI trip function code indicate on this breaker?
The LI designation means the thermal-magnetic trip unit provides fixed Long-Time thermal overcurrent protection and adjustable Instantaneous magnetic short-circuit protection.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 5 reviews.
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Rating
5 reviews
- JMJAY M.Verified BuyerReviewingSquare D MAL36600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars12/29/25POLE CIRCUIT BREAKER
SQUARE D CIRCUIT BREAKER DELIVERED REAL FAST AND AT A GREAT PRICE
- DFDavid F.Verified BuyerReviewingSquare D MAL36800 - 800A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/14/25thank you for all your
thank you for all your help
- RRyanReviewingSquare D MAL361000 - 1000A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars2/27/245 Stars
Amazing costumer service
- MCMARCUS C.ReviewingSquare D MAL36600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/4/23Great supplier /saves the Bacon every time
I did not know it shipped - I will check - you guys are great
- JMJohn M.ReviewingSquare D MAL36600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars12/13/21Clean and very well packaged
Breaker arrived as advertised. Very clean, wrapped and packed with alot of care to ensure it arrived safely.