I’ve ran into this recently and would like some clarification; I’ve seen two panels and each has a main breaker. One is clearly the distribution panel as it contains the breakers for all the components, and the bus bars are separate as they should be in a distribution panel, but it also has a main breaker. The other panel also has a main breaker and the bus bars are connected as they should be, if it’s the actual main panel. So, which is the main panel? The presence of two main breakers but with the bus bars configured correctly is throwing me.
Hi Steve, first off some photos would be helpful for accuracy. Based on what you’ve said, the first panel downstream from the service entrance would be the ‘main disconnect’ the second panel should be configured as a sub-panel even with it’s own disconnect. Post some photos if you can.
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Apologies, I’ll get some pictures uploaded for clarification. Your explanation makes perfect sense. I was circling that same conclusion but wanted feedback. I’ve only ran into that situation twice, so far anyway… Thank you!
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The main breaker at the subpanel appears to be for convenience.
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A main breaker does not determine if the panel is a service panel or simply a distribution panel. It is also possible to have 2 service panels like a typical 400 amp service.
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Sub-panels frequently need their own disconnect so it’s pretty common (not just the overcurrent breaker that feeds them in the service panel). A common example would be a sub-panel in a detached garage that served multiple circuits.
I think there was a thread on here a few months back discussing this with respect to condos where the service panel and disconnect is next to the meters in a locked room that wasn’t readily accessible to the condo owner.
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Sounds like you mean that the first panel contains the service disconnect and feeds the second panel. The conductors between the two panels would be feeder conductors if they are protected by an OCPD in the service panel. The main breaker is the second panel is likely not required.
In commercial installations sub-panels often have main breakers for convenience because the OCPD ahead of the feeder can be very far away and the single main allows the sub-panel to be easily shut down.
Should this situation be addressed in the report? If so, how should it be stated? Or simply mark the item as inspected (providing there are no notable issues)?
What is there to actually report? A second circuit breaker being used as a panel main is permitted at the end of the feeder so there is nothing abnormal to report.
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Excellent, thank you!
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What does your SoP have to say about it? Likely nothing, but double check. Your SoP does have reporting requirements beyond defects. It is always best to start there.
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Good point. Do SOP’s typically require a sub-panel to be reported as with or without a main?
It’s unlikely. But when ever someone says “Should I report on this and how?” provided there are no issue present (his words), then the only proper answer is to review the SoP.
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From Google
Safety and control purposes
In Florida, both the exterior distribution panel and the main electrical panel have main disconnect breakers. This is not typical, but it can happen due to additions or other reasons. The main disconnect breakers are used for safety and control purposes, allowing firefighters to disconnect power without pulling meters
This is not unusual in Florida homes.
No. There’s nothing to address.
Sometimes an electrical contractor will install a panel with a main breaker instead of MLO because panels with a main breaker may cost less than an MLO if they are buying them in bulk. I used to buy a lot of the same size and type panels for that reason. I could get a 200A panel at a lower cost than a 125A, 150A, or MLO.
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Morning, George. Hope to find you well.
main breaker instead of MLO?
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MLO is a common electrical term for describing a type of panel. Main Lug Only is a panel that has main lugs instead of a main breaker. Some MLO panels can be converted to a main breaker panel with a field installed main breaker kit.
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