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Kevin, Licensed Electrical Contractor
Category: Electrical
Satisfied Customers: 3665
Experience:  30 years Licensed Electrical Contractor in Illinois, Adjunct College Electrical Instructor, Former Electrical Inspector, Diploma: Digital Electronics, FCC Technician License
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Hello again Norm,,Customerhere i asked you question earlier

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Hello again Norm,,Customerhere i asked you question earlier about isolating bad 400 AMP service breaker.. And thanks again for you help.. Now i have another problem it appears I have no idea what kind or manafacture Breaker or switch it is and i go label off side but so old unreadable...
Thought maybe you had see one of these before and if i described it to you, you might be able to tell me who makes it or if that isn't important because i will have to replace entire dual switch anyways.. name is XXXXX XXXXX I will be happy to assist you with your electrical question. My goal is to exceed your expectations on Just Answer!


1) Hello... the expert that you requested is not logged-in to the site at this time. I will be happy to assist you and answer your electrical question.


2) Since the label of the 400 amp main breaker is not visible, the panel directory door located on the left-hand side should have a printed label as to the manufacturer of the electrical panel. There should be a sticker located on the door.


3) If the panel directory label/sticker has been removed, I assume this panel is a main breaker panel and has individual branch circuit breakers along with the main 400 amp breaker? If so, take a look at the individual branch circuit breakers as those should have either a label or some identification as to who the branch circuit breaker manufacturer is? If the majority of the branch circuit breakers are of the same manufacturer, this will give you a good idea as to who the panel manufacturer was.


If you have a separate main service disconnect breaker and the panel is a main lug sub-panel, check the branch circuit breakers for identification and/or labeling. If the meter socket and the main service disconnect are co-located on the same enclosure, look and see if you can locate if "Milbank" is labeled anywhere. The Milbank company is the most widely used meter socket/disconnect used in the residential market.


4) If you can post a picture here, that would be most helpful. You should have a "paper-clip" icon that you can attach a picture. Please note that sometimes, posting a picture here does not work as the site is experiencing intermittent problems with posting a picture. If not able to post a picture here, go to the website and post your picture there. Once the picture is posted, reply back to me with the URL link from the website so that I may be able to view it..............Thanks.............Kevin

Customer: replied 4 years ago.

Hello Kevin,,


I have taken a picture of panel and breakers if this will help and have more if needed didn't mean for picture to be so large once insert here so hope you can use it...


400 amp Circuit main breaker


It's a old one I am almost thinking might be easier and best to replace entire breaker with newer SquareD Bolt in main kit with 2 single lug 200 amp breakers .

Good Evening Tim............thanks for the pic.


1) Any idea as to how old the breaker is or approximately what year the home was built?


2) Do you have any nearby neighbors that may have a similar breaker where the home is a similar age that you can cross check with them if similar?


3) Nothing labeled or etched on the sides of the main breaker disconnect?

Customer: replied 4 years ago.

Hello Kevin,,


I would probaly guess the breaker to be at least 40 years old, and none of the old homes that were around back then are left in the area any more.. And i looked for anything etched or labeled anywhere on Panel or breaker, and since it is the Main disconnect can't go much deeper than to say.


The cables that feed into top of each of the 200 AMP breakers are very large and come directly from power meter above it.. I would say at least good 1/2" in size each and then have Loop lugs on each one and are screwed down in place on each breaker and Breakers appear to be just bolted or screwed down into the box.


Tim..... thanks again for your replies.


1) A 200 amp breaker will require either 2/0 copper or 4/0 aluminum which is a large conductor as you mention, approximately 1/2" diameter.


2) Based upon the picture, it is difficult to determine the manufacturer of the breaker based upon the breaker outline. It does not appear to be a Federal Pacific or a Zinsco breaker as those were very common in the 1960's and 1970's and I am familiar with those manufacturers. If I had to take an educated guess, the breaker outline appears to be either GE, Westinghouse or Siemens. The reason I mention these 3 manufacturers is that they all have a similar shape and common handle tie. Other manufacturers such as Eaton Cutler-Hammer and Square-D have more distinctive features such as the tie handle color, tie handle shapes, etc.


3) I would recommend to take your picture to a local electrical supply store and perhaps they can match up the picture of the breaker outline/form/shape to a manufacturer they have in-stock.



Hope this helps.........If you have any additional questions, let me know and I'll be glad to answer them for you.


Otherwise, don't forget to rate me before you log Off.

The next time you have an electrical question, you can also request for me at:

Kevin and 2 other Electrical Specialists are ready to help you

Hello Tim......... Thank you for the excellent service rating as well as the bonus......... much appreciated.


If you have any other questions or follow-up questions, just reply back to me at this question and I will be happy to answer them for you. No need to create a new question.


Take care and have a great weekend............Thanks..................Kevin!