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Square D MGL36300 Molded Case Circuit Breaker
- 300A
- 3 Pole
- Unit Mount
Square D
MGL36300
Molded Case Circuit Breaker
Brand
Square D
SKU
MGL36300
Quantity
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Square D MGL36300 - 300A 3 Pole Molded Case Circuit Breaker
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Description
Designed for 3-phase systems, the Square D MGL36300 is a 300A, 3-pole MCCB. Belonging to the PowerPacT M-Frame family, it provides superior protection for industrial facilities. This unit-mount device is engineered to install into standard Square D switchboards. It utilizes AL800M23K lugs to accept 3/0 AWG to 500 kcmil aluminum or copper wiring. The ET 1.0 electronic trip unit features true RMS sensing and adjustable magnetic settings (LI). It carries a 65kAIC rating at 240VAC.Specifications
| Brand | Square D |
|---|---|
| Part Number | MGL36300 |
| Series | MGL |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 18kA @ 600VAC |
| Frame Type | MGL |
|---|---|
| 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 | Electronic Trip |
|---|---|
| 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, Rotary Handle, Lug Kits |
|---|---|
| Accessories | Lugs (AL800M23K) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, IEC, NOM, UL |
| Temp Rating | -25C to 70C |
| Construction Features | HACR Rated, 80% Rated, True RMS Sensing, RoHS Compliant, Mercury Free, PVC Free |
Product FAQs
6 answersHow is the Square D MGL36300 installed?
This is a unit-mount circuit breaker designed for feed-thru connections. It bolts directly onto the backpan of compatible Square D switchboards, motor control centers, and standalone enclosures utilizing mechanical lugs on both the line and load sides.
What wire sizes do the factory lugs accommodate?
The standard lugs on this breaker accept 3/0 AWG to 500 kcmil aluminum or copper wire. Always apply the correct torque values marked on the breaker face during installation to ensure a secure connection.
How does the ET 1.0 trip unit on the MGL36300 operate?
The ET 1.0 trip unit provides solid-state protection utilizing true RMS sensing. It includes an LI configuration, meaning it offers a fixed long-time setting for overload protection and an adjustable instantaneous, or magnetic, setting to handle short-circuit faults.
Will the MGL36300 fit into a standard I-Line panelboard?
No, this specific model is a unit-mount device. It does not have the necessary plug-on jaw connectors to land on an I-Line bussing system. It is strictly for feed-thru, backpan mounting.
What does the letter G signify in the MGL36300 part number?
In the PowerPacT M-frame nomenclature, the G designates the interrupting rating tier. It signifies a maximum short-circuit capacity of 65kA at 240VAC, 35kA at 480VAC, and 18kA at 600VAC.
Is there a safe way to manually test the tripping mechanism?
Yes, the breaker features a built-in push-to-trip button on the front cover. Pressing this button manually trips the breaker, allowing you to safely verify the mechanical operation of the over-center toggle mechanism prior to commissioning.
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