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Square D Q2M3100MB Molded Case Circuit Breaker
- 100A
- 3 Pole
- Bolt-On
Square D
Q2M3100MB
Molded Case Circuit Breaker
Brand
Square D
SKU
Q2M3100MB
Quantity
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Square D Q2M3100MB - 100A 3 Pole Molded Case Circuit Breaker
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Description
Serving as a robust main breaker, the Q2M3100MB delivers 100 amps of thermal-magnetic protection for three-phase systems. It utilizes standard lug terminals for secure wire connections in commercial and industrial environments. The bolt-on design installs into compatible Square D switchboards and panelboards. It provides a 10kA interrupting capacity at 240VAC. A built-in Visi-Trip indicator allows facility managers to quickly identify tripped circuits without manual testing.Specifications
| Brand | Square D |
|---|---|
| Part Number | Q2M3100MB |
| Series | Q2 |
| Amperage | 100A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 240VAC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC |
| Frame Type | Q2M |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D Panelboards, Switchboards (Main Breaker) |
| Wire Gauge | 4 AWG - 300 kcmil (Al/Cu) |
| Max Wire | 300 kcmil |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Lugs Included |
| Standards | CSA C22.2 No. 5, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, Main Breaker |
Product FAQs
7 answersWhat type of enclosures are compatible with the Q2M3100MB?
This 3-pole main breaker is designed for installation in legacy Square D panelboards and switchboards that are configured to accept Q2M frame breakers.
Can the Q2M3100MB be used in single-phase applications?
No. This is a 3-pole circuit breaker specifically designed for 3-phase electrical systems.
What are the wire size requirements for the Q2M3100MB terminals?
The breaker is equipped with lugs that accept either aluminum or copper conductors ranging from 4 AWG to 300 kcmil.
How is the Q2M3100MB installed into the panelboard?
This breaker utilizes a bolt-on connection, meaning it must be mechanically bolted directly to the panelboard or switchboard bus assembly.
How does the trip mechanism function on the Q2M3100MB?
The breaker uses a fixed thermal-magnetic trip unit. The thermal component provides Long-Time (L) protection against sustained overloads, while the magnetic component provides Instantaneous (I) protection against short circuits.
Can the trip settings on the Q2M3100MB be adjusted in the field?
No. Both the thermal and magnetic trip functions on this Q2M frame breaker are fixed and non-adjustable.
Is the Q2M3100MB still an active Square D product line?
The Q2M series is considered a legacy MCCB frame. When replacing these units, panel builders often cross-reference them to the modern Square D PowerPact Q-frame series, such as the QBM models, provided the panelboard labeling permits the substitution.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 8 reviews.
Total 5 star reviews: 8 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
8 reviews
- MEMichael E.Verified BuyerReviewingSquare D Q221150AC - 150A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/28/26breaker purchase
delivered on time and quality was as advertised
- MWmakalita w.Verified BuyerReviewingSquare D Q232150 - 150A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/18/26Prompt service.
Well packaged
- GSGreg S.Verified BuyerReviewingSquare D Q232200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/29/25Great Job
Whenever I need a breaker and my local distributor can't handle or get what I need, Superbreakers has always come through for us.
- AWAllen W.ReviewingSquare D Q232175 - 175A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/17/22Great condition
The breakers were in great condition. The serve was also great.
- JCJim C.ReviewingSquare D Q232200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars1/13/22Great Service
My order was received fast. The packaging was perfect. The quality of the product was what was expected.