Square D QO Main Breaker Back-...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$18.27
Square D QO Main Breaker Back-Fed Load Center Accessory

Square D QO Main Breaker Back-Fed Load Center Accessory

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Model: PKSB1QOBF

In Stock (leaves warehouse same day if ordered before 3pm ET)

$18.27
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Square D QO Main Breaker Back-Fed Load Center Accessory

The Square D QO Main Breaker Back-Fed Load Center Accessory is engineered for use with the QO family of load centers, enabling a main breaker to be installed in a back-fed configuration within compatible QO enclosures. Finished in the recognizable Square D yellow, this accessory supports residential-grade electrical distribution systems where QO breakers, ground fault interrupters, and surge protection devices are used to protect equipment and occupants. As part of the QO range, it is built to help contractors and OEMs complete panel configurations that meet code-driven installation requirements.

Key Features

  • QO Series Compatibility: Designed for use with the QO range of load centers for a consistent, engineered fit.
  • Main Breaker Back-Fed Application: Supports back-fed main breaker mounting configurations within compatible QO load center enclosures.
  • Finish: Yellow color for easy identification within the panel assembly.
  • Residential Market Segment: Designed for residential electrical distribution and load center applications.
  • Country of Origin: Manufactured in the United States.
  • Packaging: Supplied 1 each per package for straightforward job-site handling.

Certifications & Compliance

  • ROHS EUR Compliant
  • Mercury Free and Toxic Heavy Metal Free construction
  • Prop 65 Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Technical Specifications

  • Toxic Heavy Metal Free: Yes
  • Take Back: No
  • Tier: 2
  • Returnability: Yes
  • Sustainable Packaging: No
  • Mercury Free: Yes
  • Packaging Without Single Use Plastic: No
  • Reach Free Shvc: Yes
  • ROHS Eur In Scope: Yes
  • Recycled Metal Content At Cr Level: 0 %
  • Legacy WEEE Scope: In
  • Packaging Made With Recycled Cardboard: No
  • China ROHS Label: 1
  • With Recycled Cardboard: No
  • WEEE Product Category: 5
  • Range Of Product: QO
  • Without Single Use Plastic: No
  • Product Availability: Stock - Normally stocked in distribution facility
  • ROHS Exemption Information: Yes
  • Reach Free Of Svhc: Yes
  • H And D Domain: Safety
  • H And D Enrichment Class 4: Enclosure accessory

Typical Applications

  • Residential Load Center Panel Configurations
  • QO Load Center Main Breaker Installations
  • Contractor and OEM Panel Assembly
  • Residential Electrical System Protection
  • New Construction and Panel Retrofits

Why Square D?

Square D backs its QO load center accessories with Mercury Free, Toxic Heavy Metal Free, and ROHS EUR compliant construction, reflecting a commitment to safe, code-compliant electrical products. Manufactured in the United States and built to integrate with the trusted QO load center platform, this accessory helps contractors and OEMs deliver reliable, professional-grade residential panel installations.

Manufacturer Resources

Product Specs

Product Type:
Panelboard Accessory
Series:
QO
Country Of Origin:
United States
Configuration:
Main Breaker Back-Fed
Product Color:
Yellow
Department:
Electrical
Product Group:
Power Distribution
Product Subgroup:
Panelboards & Load Centers
Product Height:
2.8 in
Product Depth:
0.95 in
Product Width:
1.75 in

Square D PKSB1QOBF – Frequently Asked Questions

1) What does the Square D PKSB1QOBF back-fed kit actually do in a QO load center?
PKSB1QOBF is the hold-down (back-fed breaker retainer) accessory for QO load centers. When you use a plug-on QO breaker as the main rather than feeding it from the bus, code requires that breaker be secured so it can't be pulled off the bus. This kit provides that mechanical retention inside compatible QO enclosures. It's a single accessory, 1 each per package, and it does not include the breaker itself.
2) Will the PKSB1QOBF fit a Homeline or QOB bolt-on panel?
No. The kit is built for the QO plug-on load center range only. Homeline panels use the HOM breaker platform and a different interior, and bolt-on QOB breakers in panelboards are already fastened to the bus, so no back-fed retainer applies. For a Homeline panel you need the Homeline-specific back-fed hold-down, not this one.
3) I'm converting a QO main lug panel to a main breaker. Is this part all I need?
The hold-down is one piece of it. PKSB1QOBF retains the back-fed breaker; you still have to supply the QO breaker itself at the correct amperage for the panel, and the panel's bus and interior have to accept a back-fed main breaker in that position. The kit is the retention hardware, nothing more.
4) Can an ABB THQC 1-pole front mounting plate be used in place of the Square D PKSB1QOBF back-fed accessory?
No. The PKSB1QOBF is a Square D QO series accessory for a main breaker back-fed configuration, so it is matched to QO load center enclosures. The ABB TQCFMP1 is a front mounting plate built for the ABB THQC breaker series, a different manufacturer's platform. Mounting hardware for load centers is series-specific, so a THQC plate is not an interchange for a QO back-fed accessory.
5) How much room does the Square D back-fed breaker hold-down take up inside the panel?
Small footprint: 2.8 in by 1.75 in by 0.95 in. It mounts within the enclosure at the breaker position, so it doesn't consume a circuit space the way an added breaker would. Worth checking clearance if your gutter space is already crowded with feeder conductors.
6) Is this a residential part or can I use it in a commercial panelboard?
It's built for residential load center applications on the QO platform. Commercial panelboards generally use bolt-on breakers and a different interior design, so a QO plug-on back-fed retainer isn't the right part there. For a commercial panelboard rating or conversion kit you're looking at something like the Eaton Pow-R-Stock series rating kit for PRL1X/2X and PRL1A/2A panels, which is a different class of accessory entirely.
7) What's the difference between this QO back-fed kit and a breaker mounting plate like the ABB THQC 1-pole front mounting plate?
Different jobs. The Square D PKSB1QOBF secures a QO breaker that's being fed from its load-side terminals so it can't be removed from the bus. The ABB TQCFMP1 is a front mounting plate for the THQC breaker line, which is about how the breaker mounts and is covered, not about back-feed retention. They aren't interchangeable, and neither crosses platforms.
8) What is the difference between the Square D PKSB1QOBF and the Eaton SRK series rating kit?
They do different jobs. The PKSB1QOBF is a QO enclosure accessory that supports installing a main breaker in a back-fed configuration in a compatible QO load center. The Eaton SRK is a Pow-R-Stock series rating kit for PRL1X/2X and PRL1A/2A panel systems, which addresses the panel's series rating rather than back-fed breaker mounting. Choose by the function you need and by the panel brand you are working in.
9) I am working in an Eaton panel, not a Square D QO panel - what accessory applies instead?
The PKSB1QOBF is engineered for the Square D QO load center family, so it is not the part for an Eaton enclosure. For Eaton Pow-R-Stock panels in the PRL1X/2X and PRL1A/2A families, the Eaton SRK series rating kit is the accessory offered for those panel systems. Confirm the specific panel catalog number before ordering either part.
10) Why is the Square D back-fed kit yellow?
Yellow is Square D's identification color for this accessory, and it makes the retainer obvious at a glance during an inspection or when someone later opens the panel. An inspector looking for a back-fed breaker hold-down can see it without pulling the deadfront apart.
11) Is the Square D QO back-fed accessory made in the USA?
Yes, it's manufactured in the United States. That matters on jobs with domestic sourcing requirements, including some government and institutional work.
12) Does the Square D QO back-fed kit meet RoHS requirements?
It is ROHS EUR compliant and built mercury free and free of toxic heavy metals. There is a California Prop 65 warning for cancer and reproductive harm (www.P65Warnings.ca.gov).
How fast can I get the Square D PKSB1QOBF delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Square D PKSB1QOBF come with a warranty?
Absolutely. The Square D PKSB1QOBF is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Square D PKSB1QOBF?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
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