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enter image description hereMy house was built in the late 1970's. The breaker box does not have a main breaker but it does have a double throw with two 60 amp breakers which kills power to everything in the house except for the electric stovetop. The stove top is controlled by a double throw with two 30 amp breakers. It this normal or do I have a problem?

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Richard Duncan
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    A picture of the box would help and/or the name/make of the box. You do have smaller breakers for the house circuits for lights and outlets, don't you? – crip659 May 29 '21 at 00:10
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    Can you post photos of the breaker box in question, including the label on the inside of the door, please? – ThreePhaseEel May 29 '21 at 00:15
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    Sounds like a common "rule of six" panel - but some of those happen to be brands/models that are a problem, just being there (as in they fail to work as intended and can help burn your house down) while others are perfectly fine. [edit] to include clear pictures of your panel and its labeling. – Ecnerwal May 29 '21 at 02:04

2 Answers2

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You likely have a "split-bus" panel. The NEC allowed no more than 6 switches to disconnect all power from a building. The top of the panel has space for not more than 6 two-pole breakers, one of which fed the lower section of the panel. Was legal.

Bigger issues are brand, age, and capacity to add circuits.

First brands. Zinsco and Federal Pacific have history of defects, you should consider replacing ASAP.

Second, the 2nd law of thermal dynamics, everything goes from order to disorder, things wear out. Your panel is aging to the point that a critical failure could happen at any time.

Third, many split bus services were only 100A, it sounds like you have some capacity (if you described all the significant breakers accurately), but adding a EVSE or air conditioner may be out of the question.

Also it is a bit odd to have a range on a 2p30 breaker, may be inadequate supply to Code standards, but not likely to cause any damage, just limited power available to be used at the range.

Edit: We can see it is a split-bus panel, maximum rated for 125A. It looks old enough (and since I don't see markings indicating otherwise) that the line connections are probably 60°C, it's quite possible the feed is rated less than 125A. It is still unlikely big enough for a charger or AC unit. GE panels and breakers of that era are not known to be a problem, but because of age if you were to call me and ask for a quote to replace I wouldn't ask why. An upgrade or update may also require a meter and mast replacement.

NoSparksPlease
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    @SteveSether I have some cable from 100 years ago that was never flexed and still works but the insulation is cracking and crumbling... so it has « worn out » btw it is no longer used as I replaced it and kept some as an example, actually has lead sheathing and needs external clamps for eath connections. – Solar Mike May 29 '21 at 05:02
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    @SteveSether Yes, all metal has resistance, and the heat generated by the thermal element in the thermal magnetic breakers are both elements of a thermal process. Even moisture present will cause a galvanic breakdown of dissimilar metals, which are almost always present. – NoSparksPlease May 29 '21 at 06:17
  • @Steve Sether thermodynamics is considered to apply to chemical reactions as well as to simpler systems like macroscopic heat engines. – Jim Stewart May 31 '21 at 02:09
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Yeah, that's a rule of six panel alright

What you have is a smaller split-bus panel, with a 125A top (power) section that maxes out at 4 separate 240V breakers + a submain, and a bottom lighting section that can be fed anywhere from 60 to 100A. This was used historically as a cost-saving measure before cost-effective breakers in the 125-200A range became available, but is no longer permitted by the NEC due to the difficulties it causes to folks working in the panel.

ThreePhaseEel
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  • Thanks ThreePhaseEel for your response. Would you suggest having this panel replaced? If so, any idea how much that would cost? – Richard Duncan Jun 01 '21 at 02:16
  • @RichardDuncan -- costs aren't really something that we can discuss here due to local variations. As to getting a replacement, your panel is a rather odd duck due to being made in a period where GE was transitioning breaker styles, and thus may not be able to accept current production GE THQL breakers (it's complicated), so that's the best reason I can give to replace it – ThreePhaseEel Jun 01 '21 at 02:37