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Square D MA36400 Molded Case Circuit Breaker
- 400A
- 3 Pole
- I-Line
Square D
MA36400
Molded Case Circuit Breaker
Brand
Square D
SKU
MA36400
Quantity
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Square D MA36400 - 400A 3 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D MA36400 - 400A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | MA36400 |
| Series | MA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| 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 | Load Side Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Quantity
Square D MA36400 - 400A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | MA36400 |
| Series | MA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| 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 | Load Side Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
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Description
Built for demanding electrical distribution systems, this 400A M-frame breaker provides reliable long-time and instantaneous trip functions. The component integrates smoothly into Square D I-Line panelboards, offering a secure connection without the need for complex wiring modifications. Equipped with a Visi-Trip visual indicator and HACR certification, it ensures quick fault identification. For modern upgrades, the MGA36400 serves as the manufacturer's recommended replacement.Specifications
| Brand | Square D |
|---|---|
| Part Number | MA36400 |
| Series | MA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 14kA @ 250VDC |
| Frame Type | MA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| 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 | Load Side Lugs (AL900MA) |
| Standards | CSA C22.2 No. 5, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Product FAQs
5 answersWhat panelboards are compatible with the MA36400?
This breaker is compatible exclusively with Square D I-Line panelboards and switchboards. Its plug-in mounting style attaches directly to the I-Line busway, eliminating the need for line-side wire connections.
What is the modern replacement for the legacy MA36400 breaker?
The Square D PowerPact M-frame series is the current direct replacement. Specifically, the MGA36400 is the manufacturer-recommended upgrade for this legacy 400A breaker.
What does the LI trip function code mean for this model?
The LI designation indicates Long-Time and Instantaneous protection. The breaker uses a bimetallic element for fixed long-time overload protection and an electromagnet for adjustable instantaneous short-circuit protection.
How are the trip thresholds adjusted on the MA36400?
The thermal long-time setting is fixed. However, the magnetic instantaneous trip threshold can be field-adjusted using the dials on the front faceplate to properly coordinate with downstream loads.
What are the wire size limits for the lugs on this breaker?
The factory mechanical lugs accept up to three aluminum or copper conductors per phase. Supported wire gauges range from 3/0 AWG to 500 kcmil.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
Total 5 star reviews: 1 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
1 review
- DHDave H.ReviewingSquare D MA36600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/6/25Never had a problem
We like the service and the prices. The re-certified are great for projects that we have in house.