FHB Logo Facebook LinkedIn Email Pinterest Twitter X Instagram Tiktok YouTube Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe
Log In
  • How-To
  • Design
  • Tools & Materials
  • Restoration
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
Log In

Discussion Forum

Discussion Forum

those double skinny breakers

hardluckknocks | Posted in General Discussion on April 25, 2009 12:08pm

We have a 200 amp panel. Can anyone tell why I shouldn’t use those skinny side by side 20 amp breakers. Running the older Culter Hammer.

Thanks

Reply
  • X
  • facebook
  • linkedin
  • pinterest
  • email
  • add to favorites Log in or Sign up to save your favorite articles

Replies

  1. alwaysoverbudget | Apr 25, 2009 12:35am | #1

    a lot of boxes just won't except them. if you have a 40 space box,and room for 40 breakers you will find that you can't snap these in and get more spaces. now some boxes will only have 30 lugs/40 spaces thats how you get the 40 spaces.

    all you can do is buy one and see if it will snap in. i don't think there is any problem with functionality with them as long as they match the box.

    YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'T
    MOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THE
    DUCT TAPE.

  2. JTC1 | Apr 25, 2009 12:37am | #2

    Two possible reasons:

    1) Your panel may not be listed for use with the skinny breakers.

    For example (numbers are made up):

    Some panels are listed as 30 spaces / 30 circuits - in this case skinny breakers are a no-no.

    Other panels are listed as 30 spaces / 40 circuits - in this case some of the spaces will accept the skinny breakers.

    Approved listing should be on a paper label inside of the panel.

    2) Those things are pricey!

    It depends on how many skinny breakers you want to add - may be cheaper to install a CH sub-panel or just change the older SEP to another CH panel with more spaces. I would stick with CH so your old breakers will work in new or sub panel.

    Jim

    Edit: alwaysoverbuget types faster than me! 

    Never underestimate the value of a sharp pencil or good light.



    Edited 4/24/2009 5:38 pm ET by JTC1

  3. cap | Apr 25, 2009 12:51am | #3

    Because the panel may be designed not to take 'em.  Otherwise, they work just as well as a full-height breaker. 

    In new construction, I choose a panel with enough full-height spaces to avoid using slim (pancake) or twin breakers, but I use 'em without reservation in retrofit situations.  As long as the panel is designed to accept 'em.

    Why not put pack the breakers in by using pancakes or twins?  The NEC says materials have to be used as intended by the manufacturer, and consistent with the listing (typically, the U.L. listing).

    So if the manufacturer has designed a panel to take only full height (1") breakers, then you can't use the pancake (1/2") breakers or the twins (two independent 1/2" breakers in a 1" case).  Some panels allow pancakes or twins only in some of the spaces.  Some will take pancakes in all spaces.  The idea is that putting too many breakers in a panel may lead to too much heat accumulation. 

    Another point, the bus onto which the breaker seats also may not be the right configuration for a pancake if it's intended for a full height breaker, or the rail onto which the breaker hooks may not hold a pancake securely.

    Most residential panels are "CTL" designated, that means "circuit limited", and that means no more breakers can be installed than the manufacturer intended; there are blocking mechanisms to prevent the use of pancake or twin breakers, or more of them than the panel is designed for.

    I've seen panels where an uninformed or irresponsible person has cut and filed off the blocking tab on the twin breaker so it'll fit.  Of course, I've seen panels where someone has done much worse.

    A side note, the NEC prohibits more than 42 circuits in a lighting panel (defined as a panel where more than 50 percent of circuits are lighting circuits; more meaningful in a commercial situation, where lighting and other loads are kept separate).  This requirement was instituted in the mid-1940s.  A milkbone to the first person to name the tragedy that precipitated the requirement....

    Cliff

    1. User avater
      PeteDraganic | Apr 25, 2009 04:17am | #5

      The Great Lighting Massacre of Chicago?

      <!----><!----><!----> 

      I refuse to accept that there are limitations to what we can accomplish.        Pete Draganic

       

      Take life as a test and shoot for a better score each day.          Matt Garcia

    2. User avater
      jonblakemore | Apr 25, 2009 05:28am | #6

      Cocoanut Grove? 

      Jon Blakemore RappahannockINC.com Fredericksburg, VA

    3. User avater
      BillHartmann | Apr 25, 2009 05:33am | #7

      "A side note, the NEC prohibits more than 42 circuits in a lighting panel"I understand that this changed in the 2008 NEC, but have not seen it.And that Canadian code allows much better.But I don't think that the larger panels are yet common available in the US.BTW, I had never seen a 42 breaker panel, single phase. Although I know that they exist.But I saw one one of the home horror stores the other day as a value pack. It might have been a Murry, but not sure..
      William the Geezer, the sequel to Billy the Kid - Shoe

      1. JTC1 | Apr 26, 2009 01:58am | #12

        >>BTW, I had never seen a 42 breaker panel, single phase. Although I know that they exist.<<

        The main panel in my house is a 200a, Cutler Hammer, CH breakers - has a cover marked for 42 spaces.  Notice I said the "main panel" as there are 2 sub-panels pulled off of it, a 60a and a 100a - all Cutler Hammer, all CH breakers - have never had any problems with any of them.   All installed circa 1994.

        The humorous detail is that there are 42 spaces marked and twist-outs provided for 42 slots on the cover ( yes, the cover is the one specified for this panel).

        However, there is no buss connection bar available for slot #41 or #42 inside of the panel - they are too short!

        So the reality is that it is a 40 slot panel.  I have the bottom two twist-outs marked with a red X and the word NO - just as a reminder for my failing memory!

        Glad we did not start the single pole breakers at the bottom and work up and blindly removing twist-outs from the cover as we went.

        Would have been humorous - "hey, this cover doesn't fit right" ; snap out two more twist outs; "that's better ----hey, now there's two holes at the bottom!" "Aw man, now I gotta get those plug'em up thingys." I hate when that kind of stuff happens.

        JimNever underestimate the value of a sharp pencil or good light.

        1. User avater
          BillHartmann | Apr 26, 2009 02:57am | #14

          I wonder if that box was orginally designed for 3 phase service? 42/3 gives 14 breakers on each leg. split left and right 21 breakers on each size.And then they decided to change the guts for single phase..
          William the Geezer, the sequel to Billy the Kid - Shoe

          1. JTC1 | Apr 26, 2009 10:24pm | #20

            Don't know what the story is / was.

            Panel and cover bought by licensed pro from a large electrical supply house here in town.  We worked together on the whole project, I did 99% of rough and trim - he taught me a lot - he checked my work, lent advice, pulled permits and made arrangements with POCO.

            Just glad we did not snap out those two bottom tabs in the cover.

            JimNever underestimate the value of a sharp pencil or good light.

  4. user-253201 | Apr 25, 2009 01:00am | #4

    Hardluck,

    If you want to be code compliant, you can only use the twins if the box is specifically labeled for twins.

    Will the twins fit in your box?............I know they will in a GE box, not sure about CH.

    Will it work with out problems?..........Probably

    Will it be code compliant?.................. NO, because if its not labeled for twins, the box was not tested with twins, the manufacture won't sign off on it with out the testing and the AHJ will not sign off on it without the manufacture's blessing.

    Is it often done anyway?............... I've seen it done more than once, but it would not have passed an inspection.

    Regards Rich

  5. RFM 2 | Apr 25, 2009 05:54am | #8

    The older Cutler-Hammer type CH panels are not able to accept a twin/skinny/tandem/piggyback breaker they did start manufacturing one but the panels they fit are limited & if a panel is not marked to accept a twin it violates the listing to use it, I was POed when they did introduce the CHT breaker, as that is one of the nice features of that line of loadcenters: NO FREAKING TWINS!

    Cutler-Hammer makes 2 lines of panels: Their original line, the type CH "classic",and the former Bryant/Westinghouse type BR line, the type CH is the last decent residential/light commercial loadcenter that has not been cheapened to the same extent like SQ D QO has been & the BR line is the mark of a low end/trunk slammer job.

    1. hardluckknocks | Apr 25, 2009 02:55pm | #9

      Glad i asked. thanks for all the replies.That's funny, i put a twin in and the inspector didn't catch it last time he was here when i put a 100 amp sub for the barn. And i'm sure as it was pointed out that my box isn't designed for them - they're 20 ampsas i'm just a dyi-er, are those 'arc fault' breakers worth the money?

      1. Scott | Apr 25, 2009 06:56pm | #10

        I don't know what some of the other posters mean by "older" CH panels, but I've been using the skinny ones since 2000. Everything was bought new at Home Cheapo. No problems so far.Scott.

        1. RFM 2 | Apr 26, 2009 01:29am | #11

          Your using the Cutler-Hammer garbage line which is the former Bryant/Westinghouse residential/light commercial load center line it became part of the C-H lineup when C-H's parent Eaton bought the electrical portion of Westinghouse Electric Corporation.The "BR" frame breaker is 1" wide & the other C-H line "CH Classic" is 3/4" wide per pole.On another note: The BR line is advertised as "Engineered Value" which in plain English means "cheap".

          1. Scott | Apr 26, 2009 05:51am | #15

            For "garbage" (your words, not mine), it has performed well. No nuisance trips from AFI or GFI, reasonable fit and finish, no stripped threads or broken mounts, no loose lugs after almost 10 years, and no defective breakers. I've got nothing to complain about. Have you?Scott.

          2. RFM 2 | Apr 26, 2009 07:31am | #16

            It's a bottom feeder panel picking up where Zinsco left off, I judge a building by the electrical gear, & when one finds cheap gear in place, do not usually have to look much farther to see poor construction elsewhere because if folks don't care about the electrical, they don't care much about anything else either.

          3. alwaysoverbudget | Apr 26, 2009 04:30pm | #17

            so give me your opinon on whats a good box.

            seems to me most boxes seem good when new then 20 years down the road the problems show up.

            just yesterday i replaced a fedral pacific box. i'm sure when this box was new it was considerd a good box back in the 50's.they are probably the most popular box around here from that time period.now they are bad news,some insurance companies won't write ins with them.

            just for disscusion i put in a semiens [?] seems good ,but we'll know in 20 years.

            i have a ge box in my house and 3 semiens sub paneled off,everything seems fine so far........................YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'TMOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THEDUCT TAPE.

        2. hardluckknocks | Apr 26, 2009 02:38am | #13

          ours was put in 1998 so the doubles don't have the same 'tail' on the opposite side of the place where it snaps on and gets its juice.but they've been working for the last couple years - but i think now that i know what the scoop is i'll change them back.

  6. danski0224 | Apr 26, 2009 05:23pm | #18

    I have a Cutler Hammer CH12M100 panel in my house- probably 1967 ish vintage.

    The double breakers fit in mine, and there have been no problems.

    It would be nice if I could get new "guts" for the box, as there are 3 or 4 exposed mounting locations for the bus bars.

    I will be installing a few more double breakers to gain room for a small, but useful, garage feed.

    As to code issues regarding the double breakers, I don't know. I do not have everything on at the same time, so the load capacity is never approached, and I understand that is separate from code compliance issues.

    1. User avater
      BillHartmann | Apr 26, 2009 08:40pm | #19

      FWIW I don't know when the CTL system came into being. But I am sure that it was well after 67. I am guessing in the 90's maybe even this century.But for older panels they made tandems without the exclusion feature. It used to be common that the box stores and hardware stores only stocked those.But that might be a local bases of which type they stock. Don't know.2nd FWIW Cutler Hammer has a series of retro-fit panels. They consists of the guts and a new cover. You reuse the old box.They come in several standardized sizes and both BR and CH series.They are special order and hard to find the info on their website.And probably most distributors don't know about them either..
      William the Geezer, the sequel to Billy the Kid - Shoe

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Video Shorts

Categories

  • Business
  • Code Questions
  • Construction Techniques
  • Energy, Heating & Insulation
  • General Discussion
  • Help/Work Wanted
  • Photo Gallery
  • Reader Classified
  • Tools for Home Building

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Up Next

Video Shorts

Featured Story

FHB Podcast Segment: Efficient HVAC for a New Build

Self-installing an HVAC system requires a lot of thought and planning.

Featured Video

How to Install Exterior Window Trim

Learn how to measure, cut, and build window casing made of cellular PVC, solid wood, poly-ash boards, or any common molding material. Plus, get tips for a clean and solid installation.

Related Stories

  • Podcast Episode 686: Brick Steps, Ground-Source Heat Pumps, and Greenhouses in Nova Scotia
  • FHB Podcast Segment: Efficient HVAC for a New Build
  • Affordable Scans, Accurate Plans
  • FHB Summit 2025 — Design, Build, Business

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Fine Homebuilding Magazine

  • Issue 331 - June 2025
    • A More Resilient Roof
    • Tool Test: You Need a Drywall Sander
    • Ducted vs. Ductless Heat Pumps
  • Issue 330 - April/May 2025
    • Deck Details for Durability
    • FAQs on HPWHs
    • 10 Tips for a Long-Lasting Paint Job
  • Issue 329 - Feb/Mar 2025
    • Smart Foundation for a Small Addition
    • A Kominka Comes West
    • Making Small Kitchens Work
  • Issue 328 - Dec/Jan 2024
    • How a Pro Replaces Columns
    • Passive House 3.0
    • Tool Test: Compact Line Lasers
  • Issue 327 - November 2024
    • Repairing Damaged Walls and Ceilings
    • Plumbing Protection
    • Talking Shop

Fine Home Building

Newsletter Sign-up

  • Fine Homebuilding

    Home building tips, offers, and expert advice in your inbox.

  • Green Building Advisor

    Building science and energy efficiency advice, plus special offers, in your inbox.

  • Old House Journal

    Repair, renovation, and restoration tips, plus special offers, in your inbox.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters

Follow

  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X
  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences
  • About
  • Contact
  • Advertise
  • Careers
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2025 Active Interest Media. All rights reserved.

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

  • Home Group
  • Antique Trader
  • Arts & Crafts Homes
  • Bank Note Reporter
  • Cabin Life
  • Cuisine at Home
  • Fine Gardening
  • Fine Woodworking
  • Green Building Advisor
  • Garden Gate
  • Horticulture
  • Keep Craft Alive
  • Log Home Living
  • Military Trader/Vehicles
  • Numismatic News
  • Numismaster
  • Old Cars Weekly
  • Old House Journal
  • Period Homes
  • Popular Woodworking
  • Script
  • ShopNotes
  • Sports Collectors Digest
  • Threads
  • Timber Home Living
  • Traditional Building
  • Woodsmith
  • World Coin News
  • Writer's Digest
Active Interest Media logo
X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Project Guides
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Online Learning

  • Courses
  • Project Guides
  • Reader Projects
  • Podcast

More

  • FHB Ambassadors
  • FHB House
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • X
  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 70%

Subscribe

Enjoy unlimited access to Fine Homebuilding. Join Now

Already a member? Log in

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in

Privacy Policy Update

We use cookies, pixels, script and other tracking technologies to analyze and improve our service, to improve and personalize content, and for advertising to you. We also share information about your use of our site with third-party social media, advertising and analytics partners. You can view our Privacy Policy here and our Terms of Use here.

Cookies

Analytics

These cookies help us track site metrics to improve our sites and provide a better user experience.

Advertising/Social Media

These cookies are used to serve advertisements aligned with your interests.

Essential

These cookies are required to provide basic functions like page navigation and access to secure areas of the website.

Delete My Data

Delete all cookies and associated data