Electrical panel labeling or numbering standard

Discussion in 'Electrical Forum discussion & Blog' started by Gurrenteed, Jul 29, 2020.

  1. Gurrenteed

    Gurrenteed New Member

    Joined:
    Jun 22, 2017
    Location:
    Shawnee, KS
    Hi. I’ve googled trying to find the answer to this but the more I search, the less confident I get.

    I am hoping that someone can help me answer a question. I live in the US - specifically Kansas - and I am a firefighter by trade. I’m fairly certain that there’s an answer for this in the NEC, but I can’t find it.

    Recently, we had an apartment fire that involved some appliances. One of the fireground tasks is to secure utilities - or DC power to the involved occupancy. Most of the time this is simply flipping the main breaker at the circuit panel. Sometimes, there is no “main” on the panel (which I’d assume technically makes it a sub-panel?) and we have to switch everything in the panel to the off position. Either way, we always have to pay very close attention to the position of the breakers as found because this needs to be clearly communicated to the fire investigator. On this particular fire, the smoke was thick enough that I had to go into an adjacent apartment to figure out the layout and location of the electrical panel so I could find it in the fire apartment. It ended up being in the back wall of a kitchen pantry with no “main” on the panel. After finding it, I saw all breakers “on” except for two that appeared to have tripped - a 240 circuit and 120 circuit. They were the 2nd, 3rd, and 4th space on the right column. Smoke staining and visibility prevented me from reading any labels or numbers. I turned off the other breakers and left these in the tripped position as an additional form of evidence for the investigator. I have very limited knowledge of electrical code, but I have always assumed that the left column is odd and the right column is even, but now I’m wondering if this is even a standard or if it’s just how most electricians in my area do this?

    When I reported this to the investigator, I described the location of the tripped breakers: right column - 240V in the 2nd/3rd space and a 120V in the 4th space. I also referred to the breakers as number 4, 6, and 8 during our discussion, which I’m now wondering if I was wrong for assuming it was labeled this way since I couldn’t actually see the labels. After considering that I couldn’t actually see the labels, I found the investigator on scene and clarified my report on the findings so there wouldn’t be any confusion.

    Since this fire I’ve been curious... I have asked a few fire investigators but I’ve had some conflicting answers on this. Anyone know the answer? Thanks.
     
    Reach4 likes this.
  2. WorthFlorida

    WorthFlorida The wife is still training me.

    Joined:
    Oct 28, 2009
    Occupation:
    Retired
    Location:
    Orlando, Florida
    There is no order for breakers. For 240v circuits, by the amp rating and the wire type you can come up with a good guess but a licensed electrician or an fire investigator must make the determination. On the breaker panel the circuit numbers are etched into the steel faceplate. Odds numbers on the left, even on the right.
    I'm surprised a fire investigator has not made this determination. A tripped breaker doesn't mean the source of the fire. A wire nearby in the wall or a table lamp cord melting can trip a breaker.
     
    Speedy Petey likes this.
  3. Sponsor

    Sponsor Paid Advertisement

     
    Speedy Petey likes this.
  4. Gurrenteed

    Gurrenteed New Member

    Joined:
    Jun 22, 2017
    Location:
    Shawnee, KS
    I realize that a trip doesn’t equal cause (and believe me, the investigators definitely realize this and their reports go into great detail when it is an electrical cause... not just saying “yep, oven was tripped so the fire started there”) but preserving all evidence for the investigators is extremely important.

    Some investigators have said its fine to report circuit spaces such as: 2nd, 3rd, 4th space on the right column. Some have said they don’t mind it being reported as what I would consider a standard number for the panel as long as I describe the layout: #4, 6, and 8 with left column odd, right column even, smallest numbers on top.

    I was just hoping there would be a standard... that’s alright though. Thanks for the answer!

    Edit: also, the panel was labeled and the numbers were stamped on the panel... but many times these things are not visible during firefighting operations.
     
  5. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    Depending on the actual CB installed, they can take anywhere from 1/2 of a slot to 2, and if it's commercial and potentially multiphase, maybe even more.

    If there isn't a main breaker, there probably is a main shutoff for the unit somewhere, maybe the end of the building
     
  6. Stuff

    Stuff Well-Known Member

    Joined:
    Mar 7, 2013
    Location:
    Pennsylvania
    Here is a panel that goes 1-20 on the left and 21-40 on the right: https://structuretech1.com/wp-content/uploads/2012/02/panelboard-diagram-4-356x500.jpg (notice it doubles up at the bottom). You can see how half size breakers can really throw the numbering off (as a twist GE labels a and b for half each space).

    Since there are no universal standards you need to report what you see and document it. If you say "3rd breaker down from the top on the right (#6)" then you can legitimately call it #6 in the rest of your report.
     
Similar Threads: Electrical panel
Forum Title Date
Electrical Forum discussion & Blog Buried/Recessed Electrical Box w/ Access Panel Apr 3, 2020
Electrical Forum discussion & Blog Zinsco Electrical panel question Mar 3, 2019
Electrical Forum discussion & Blog In ground Pool removal- Electrical panel options Sep 7, 2018
Electrical Forum discussion & Blog Electrical panel- no ground Feb 1, 2017
Electrical Forum discussion & Blog Electrical Panel in closet. A no no but what if... Oct 29, 2013

Share This Page