Double Pole Across Left And Right Side of Box? - Page 1
Forum section: electronics / beginners

author: tommygdawg
author_rank: Contributor
timestamp: August 24, 2016, 12:20:36 am
content: Hey, allLooking at my breaker box in the basement, there's all sorts of single and double pole breakers in there. I was wondering though, why are double pole breakers always on top of each other, rather than across the box? That is to say, one pole on left and one pole on right.I'd like to have another double pole installed in my box, but it's only got two slots free at the bottom...to the left and right, but not on top of each other like the typical double pole. Any thoughts? Thank you!

author: Shock
author_rank: Super Contributor
timestamp: August 24, 2016, 01:52:36 am
content: The breakers sound like two rows vertically mounted. Which explains why the double breakers look like they are on top of each other (when in fact they are probably side by side vertically). It's likely you can move a single breaker across and install another double breaker in the gap. Talk to your electrician.Example below if they are a similar style, they are modular and can be moved about, it's just code you need to worry about, don't do this yourself if you die or burn the house down no insurance for you.

author: tommygdawg
author_rank: Contributor
timestamp: August 24, 2016, 01:56:17 am
content: Oh cool, that's exactly how mine is setup! That makes life easier. Thanks for the responseIs the separation into two vertical rows just for organizational purposes, then?

author: Monkeh
author_rank: Super Contributor
timestamp: August 24, 2016, 02:29:58 am
content: Quote from: tommygdawg on August 24, 2016, 12:20:36 amBecause they need to be mechanically linked.

author: ConKbot
author_rank: Super Contributor
timestamp: August 24, 2016, 04:15:38 am
content: Quote from: tommygdawg on August 24, 2016, 01:56:17 amLook at the bus bars in the center, the one on the left is one leg, the one on the right is the second leg, the bus "stabs" (the metal fingers sticking up) alternate, left leg, right leg as they go down, and the breakers straddle the stab with a clip to make the connection.So breakers horizontally adjacent are on the same leg, vertically adjacent are on different legs. So for your 240v circuits, 2 vertically adjacent breakers with a linked handle are used. The breakers have to be linked, otherwise opening the breaker on phase 1 but not phase 2, with a load connected would end up with 120v still being present on the wire you thought you made safe by turning off the breaker.For your situation, just move a breaker from one side to the other so you have 2 vertically adjacent slots to use.Another gotcha, (for US only, other stuff can vary by country) if you happen to be installing a subpanel because your main panel is running short, is that neutral and ground wires can only be tied together at the main panel. A subpanel will have an isolated/insulated neutral bus, and a ground bus which is tied to the metalwork.There may be exceptions for external buildings with subpanels, I.e. Detached garages and sheds, where the panel gets its own ground stake, so check up on your local code if that's what you're doing.

author: tommygdawg
author_rank: Contributor
timestamp: August 24, 2016, 05:14:34 pm
content: ConKbot, thanks so much for the detailed response. It's incredibly helpful. A quick question, will it affect anything drastically if I move one single pole breaker to the left and then down one? I've attached a photo of my box. As you see I'll have to move the bottom 40A breaker down one and then move a single pole from the left side over to the right. That shouldn't be an issue I'd imagine? It might affect the load balancing I guess?

author: ConKbot
author_rank: Super Contributor
timestamp: August 25, 2016, 12:07:36 am
content: Quote from: tommygdawg on August 24, 2016, 05:14:34 pmMoving one breaker will change the load balance slightly, but it won't be causing any problems unless you had one to begin with.In a typical US residential panel, it is hard to get an imbalance large enough to be problematic without almost comical amounts of negligence since the heavy loads are generally 240v. Something like managing to put all the kitchen, bedroom and living room outlets on the same leg, with lights on the other.

author: tommygdawg
author_rank: Contributor
timestamp: August 25, 2016, 02:26:57 am
content: Quote from: ConKbot on August 25, 2016, 12:07:36 amThanks again, ConK. Makes a lot of sense! So, in keeping with the load balancing topic...is there an issue with placing two double breakers right next to each other? I've attached another photo of how I see my new 100A breaker fitting into the box.This is my main plan. I have a light draws 55A on it's electric ballast and 68A on it's magnetic ballast. Lowes/Home Depot only had breakers at the 60A level or the 100A. So I got the 100A and will be running AWG 2 wire (hot, hot, ground) that ends in camlocks that can plug into my ballast. I've attached that photo as well.Now, I don't see the 100A being on the same poles as the 40A stove a problem because I can't ever imagine a time when I'd run the stove *AND* the 12,000 watt light on the 100A breaker at the same time.

author: ConKbot
author_rank: Super Contributor
timestamp: August 25, 2016, 06:33:46 am
content: Load balance is purely about not having excess neutral current going out of your panel back to the transformer, 240v loads don't have a neutral current.2AWG is protected sufficiently with a 100A breaker, so that is acceptable. I'm not sure if camlocks would be an allowable receptacle for meeting disconnect requirements (this may be more of my commercial experience bleeding over, but all loads other than lighting should be able to be made safe from the room they are in, either by a plug or a disconnect switch. ) since you can easily run it without the ground, and one of the line plugs will be live when you disconnect it, until you disconnect the other line plug.A disconnect switch between the breaker and cam lock sockets would probably be required by code, and you could put 70 or 80A fuses in it to protect the equipment in case if a fault. But if your cam lock sockets are adjacent to the panel and you want to switch them with the breakers, and aren't using it that much, it wouldn't be the end of the world(unless the inspector came out). Just be aware that breakers are only good for a couple hundred manual actuations, and a dozen or so fault trips. So if you're going to be flipping the breaker often, plugging and unplugging the camlocks, you may get nuisance trips, or you may get a breaker that didn't break until the wire was on fire.Plus it's easy to lock the disconnect switch off, if the cam lock sockets aren't finger safe and little ones are around.

author: amyk
author_rank: Super Contributor
timestamp: August 25, 2016, 10:24:35 am
content: I'm curious what the main breaker is rated at if you're putting a 100A one in the subcircuit.

author: tommygdawg
author_rank: Contributor
timestamp: August 25, 2016, 09:39:50 pm
content: Quote from: ConKbot on August 25, 2016, 06:33:46 amThank you so much. I really appreciate all of your indepth explanations. It's made everything very clear. I'll probably just do as you said and get a big 'ol disconnect switch and wire it up before the camlocks. Then when I need the power I can just flip the switch on.Quote from: amyk on August 25, 2016, 10:24:35 amThe main breaker is rated at 150A, though I don't ever plan to run my 100A subcircuit at it's max capacity. I may run it at 90A in very special circumstances, but it will in almost all circumstances be in the 50-70 range.

author: ConKbot
author_rank: Super Contributor
timestamp: August 26, 2016, 12:58:34 pm
content: Quote from: tommygdawg on August 25, 2016, 09:39:50 pmIts easier to convince some people (the kind of people that would be installing a 12 kw lamp on their own) to do something if they know why, rather than just "code sez"A lot of things to NEC come into play under fault conditions, that normal common sense may not make clear to a person who doesn't see the big picture, or for safety considerations that aren't that unreasonabe. I.e. The breakers on 240v circuits being tied together. (One will stop the fault current why turn off both? ) Or not using breakers as a switch everyday. (Looks like a switch, sounds like a switch, functions like a switch, why expect it not to be)That and disconnects aren't that expensive if they aren't 600v rated models, and they have a satisfying thud when you operate it.Also, when a generator inevitable gets plugged into the camlocks, cut the main breaker. You dont have a good way to power a load from the cam locks, but also have an interlock on the MCB, so it'll never meet code. But if it does happen, always remember to open the MCB, it could be the life of a linesman if you don't.