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Zinsco QC55 Molded Case Circuit Breaker

  • 55A
  • 2 Pole
  • Plug-On
Zinsco QC55
Molded Case Circuit Breaker
Brand Zinsco
SKU QC55
Select Item Condition
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  • 55A
  • 2 Pole
  • Plug-On

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Zinsco QC55 2 Pole Circuit Breaker

Zinsco QC55 - 55A 2 Pole Molded Case Circuit Breaker

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$32.36 No Stock

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Description

Sourcing exact replacements for discontinued electrical systems is critical, and this 55A molded case breaker fulfills that need for vintage properties. It supplies essential thermal-magnetic protection for 120/240V branch circuits. This component installs into classic Zinsco and Sylvania load centers without requiring adapter hardware. If utilizing the UBIZ250 substitute, users must downsize the circuit to 50 amps. It features a 10kAIC rating and common trip functionality for safety.

Specifications

Key specifications
Brand Zinsco
Part Number QC55-R
Series QC
Amperage 55A
Poles 2
Mounting Style Plug-On
Voltage 120/240VAC
Phase 1
AIC Rating 10kA @ 120/240VAC
Fit and installation
Frame Type QC
Terminal Type Lugs
For Use With Zinsco Load Centers, Sylvania Load Centers
Wire Gauge 8 AWG - 1/0 AWG
Max Wire 1/0 AWG
Min Wire 8 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed
Standards and features
Standards UL 489
Approval UL
Temp Rating 40C
Construction Features HACR Rated, Common Trip

Product FAQs

4 answers
Which load centers are compatible with the Zinsco QC55 circuit breaker?

The QC55 is designed for use in classic Zinsco and Sylvania load centers that accept Type QC plug-on breakers. It installs directly onto the bus bar without the need for adapter hardware.

What are the alternate catalog numbers for the Zinsco QC55?

This 55A breaker serves as a direct replacement for legacy part numbers including QC255, QC-55, and Q255.

Is there a modern Connecticut Electric UBIZ replacement for the 55A QC55?

Connecticut Electric does not manufacture an exact 55A UBIZ replacement. If utilizing a modern substitute, users must downsize the circuit to 50 amps using the UBIZ250, provided the application allows for the reduced amperage.

Does the Zinsco QC55 include common trip functionality?

Yes, this 2-pole breaker features an internal common trip mechanism. If one pole experiences a fault, both poles will trip simultaneously to disconnect power across the 240V circuit.

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Reviews

5.0
Rated 5.0 out of 5 stars
Based on 15 reviews
Total 5 star reviews: 15 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Rating
Ratings
15 reviews
  • DS
    Denise S. A.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer QC3070H - 70A 3 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/4/25
    Great turn around!

    My experience was great. I had the item quickly; and it was more reasonably priced than other places I checked. Not having to pay freight was an absolute bonus.

  • DM
    Douglas M.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer QC1020 - 20A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/28/25
    Just what I needed

    Ordering was easy and the processing was immediate. The beakers I ordered was exact. I recommend this company for your needs.

  • GL
    Gianna L.
    Flag of United States
    Reviewing
    Eaton / Cutler-Hammer QC1015 - 15A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    11/27/23
    Great

    as advertised!

  • ED
    Elmer D.
    Flag of United States
    Reviewing
    Zinsco QCAL100 - 100A 2 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/28/23
    Very accurate, delivered on time

    Very accurate, delivered on time and fixed my problem good job

  • RB
    Rawle B.
    Flag of United States
    Reviewing
    Eaton / Cutler-Hammer QC1015 - 15A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/8/23
    SuperBreakers had the parts I

    SuperBreakers had the parts I needed in stock, was shipped and delivered on time. Great service!