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Square D MH320 - 20A 3 Pole Miniature Circuit Breaker

Brand Square D
SKU MH320
5.0
Rated 5.0 out of 5 stars
3 Reviews
Square D MH320 3 Pole Circuit Breaker
Free Shipping Over $99
Square D MH320 3 Pole Circuit Breaker

Square D MH320 - 20A 3 Pole Miniature Circuit Breaker

Brand Square D
SKU MH320
5.0
Rated 5.0 out of 5 stars
3 Reviews
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Earn 102 SuperPoints

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Square D MH320 3 Pole Circuit Breaker

Square D MH320 - 20A 3 Pole Miniature Circuit Breaker

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$102.73 No stock

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DescriptionSpecificationsSuperClubWarranties
Description
Providing essential overcurrent protection, this 20-amp miniature breaker handles three-phase commercial loads. The unit utilizes proven thermal-magnetic trip technology to safeguard wiring against overloads and short circuits in demanding environments. Installs into legacy Square D MH panelboards to keep existing distribution systems operational. Facility engineers can also use the QOB320 as a verified substitute when replacing components in these specific older enclosures.

Specifications

Brand Square D
Series MH
Part Number MH320
Amperage 20A
Voltage 240VAC
Poles 3
Phase 3
AIC Rating 10kA @ 240VAC
Mounting Style Bolt-On
Terminal Type Box Lugs
For Use With Legacy Square D MH Panelboards
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed
Wire Gauge 14-8 AWG (Al/Cu)
Max Wire 8 AWG
Min Wire 14 AWG
Accessories Load Side Lugs Included
Standards UL 489, CSA C22.2 No. 5
Approval UL
Temp Rating 40C
Construction Features Visual Trip Indicator

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Warranties

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When shopping with SuperBreakers, you’ll have peace of mind knowing that every single item you purchase includes a 60 day warranty, free of charge. Why such confidence? Because only the highest quality electrical parts have a place on our shelves, and we stand by every single one we sell.

If anything goes wrong with your item that is not a result of misuse or normal wear and tear, we’ll gladly replace it at no cost to you.

Click here to read our full warranty details

Shipping

Free Shipping Policy

Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.

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Same Day Shipping

We strive to ship out your items the same day the order is placed. In rare circumstances SuperBreakers may reserve up to 5 business days to consolidate orders for complete shipment.
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Orders being shipped via Next Day Air, 2 Day Shipping or 3 Day Shipping must be received by 3 PM EST to guarantee same-day shipments. Expedited orders only ship on normal business days. Shipments will NOT be sent out on Saturdays and Sundays.
International Shipping

All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.

5.0
Rated 5.0 out of 5 stars
Based on 3 reviews
Total 5 star reviews: 3 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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3 reviews
  • SB
    Steve B.
    Verified Buyer
    Reviewing
    Square D MH36600 - 600A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    1/23/26
    Square MH36600

    Breaker was as advertised excellent condition

    Was this helpful?
  • SA
    Stewart A.
    Flag of United States
    Reviewing
    Square D MH38 Panel Board Enclosure
    I recommend this product
    Rated 5 out of 5 stars
    3/25/19
    not at local supply

    got what I needed, because it was not available at my local supply house.

    Was this helpful?
  • WW
    William W.
    Flag of United States
    Reviewing
    Square D MH32 Panel Board Enclosure
    I recommend this product
    Rated 5 out of 5 stars
    7/1/18
    INSIDE THE BOX

    Great Buy ! Shipped on time. No Damage. Just what we ordered Thanks

    Was this helpful?

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