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How far off the floor should my circuit breaker box be? I'm changing from a 100 to a 200 amp. The lead in wires are underground and come into the bottom of box making them too short to connect.

  • In MN. Service panel yes. In MN. Tried finding that out without luck. Thanks for the reply. – Pete Oct 24 '15 at 23:25
  • @PJMahoney, this is not something to be guessing at or assuming. There is NO national minimum code height, and this is not something I have ever heard of there being a local amendment on either, although it's certainly possible. – Speedy Petey Oct 25 '15 at 1:16
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I don't think there's a minimum height, but there's a maximum height for breaker handles.

240.24 Location in or on Premises.

(A) Accessibility. Overcurrent devices shall be readily accessible and shall be installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft 7 in.) above the floor or working platform...

So for a main breaker panel, where the main breaker is at the top. The center of the main breaker handle, cannot be higher than 6' 7".

Check with the local building department, as they may have a minimum height.

Practically speaking, you'll want it at a comfortable height to work in. You're not going to want to sit, or kneel on the floor while working in the panel.

  • Thanks for the explanation. The code I read said 6.5" but nothing related to the handle. This makes more sense. – Pete Oct 24 '15 at 23:30
  • @Pete, if what you read did not reference the operating handle and said 6.5', then what you read was not the actual code. – Speedy Petey Oct 25 '15 at 16:18
  • You're right, it didn't so that's what lead me here. I'll call a local electrician tomorrow. Thanks again. – Pete Oct 25 '15 at 19:45
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You say you are replacing a 100A panel with a 200A, but the wires won't reach??? It is almost a certainty that you will need to replace the wires. It is extremely unlikely that they originally ran wire large enough for a 200A service, yet only installed a 100A panel.

Also, with pretty much all new main-breaker panels, the breaker can be mounted top or bottom, meaning there is no such thing as an "upside down" panel. Having the main breaker on the bottom will make for a cleaner and simpler installation where the feeders come in the bottom.

  • 1
    @Pete, any comment on upgrading just the panel, or is this a complete service upgrade? – Speedy Petey Oct 25 '15 at 16:19
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You should check if your new panel (or return it and buy a new panel that) can have the main at the bottom. My 200 amp panel (Sq D QO - evidently "convertible") is labeled/listed for both directions. My habit-following electrician (I do many things, but hired a pro for the main service connection) was about to complicate life considerably by trying to put them at the top when I pointed out that not only could they be installed main-on-bottom, but the customer wanted them that way ;-) and it simplified the installation considerably, since power was entering at the bottom. On that particular panel there's no potential confusion about "where's the main", since it's 4 times the size of a regular breaker and extends across both rows of regular breakers. You might look on top first, but you'd see it on the bottom right quick.

You'd still have to respect the 79" height to the center of the last row of regular breakers (which are the top with the main on the bottom.)

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There is a minimum height from the floor to the bottom circuit breaker. I thought it wa 3'9". But I can't find it in the NEC yet.

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  • 2
    No there isn't, that's why you're not finding it anywhere in the NEC. An 84-space, main breaker, NQ panelboard uses an 80" high cabinet -- with a bottom feed, you'd basically need to have the cabinet bottom at the floor in order to keep the uppermost spaces within the 6'7" limit on breaker handle heights. – ThreePhaseEel Dec 4 at 5:47
  • What @ThreePhaseEel said. You could mount the panel on grade if you wanted to, indeed some large panels you pretty much have to. Nice explaination from EC magazine. – bishop Dec 4 at 5:55

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