Electrical Help - Breaker Panel

[chatyak]

Looking for some advice please.

My breaker panel box is a Siemens. I am planning on installing 2 more circuits on 15 amp single pole Siemens breakers.

How can I tell if my panel can handle the additions? I took the cover off and looked at the info but it wasn't very clear.

The two main breakers in this pic have "100" on them. This is a 100 amp panel correct? I know it has a max # of circuits it can handle, but I don't know what that is.

If it is a 100 amp panel, why the do the numbers on the circuit breakers add up to more than 100? So long as the total amperage does not exceed 100 at any given time, all is well correct?

Ex) You could have ten 15 amp breakers, but each circuit carries much lower total amps than 15.

My other questions are in the following picture:

The person that did this wiring before did it wrong and I had it fixed - but I am curious about the ground wire. When I install new circuits, the different ground wires may touch/overlap due to so much slack. Is this going to cause a problem? Should I snip the ground wire excess and clean it up? What happens if different ground wires touch each other. Is this a concern? What if the ground wire is touching the breaker panel box itself (not just the grounding bar).

 

[Mark Bianco]

Your ground wiring concerns are not an issue yes they can touch and the box as well after all the ground lug is connected directly to the box, grounded boxs are a good thing. If you want to "clean it up" that not a problem but not necessary.

Even though your total amperage rating of breakers load exceeds the maximum of the main breakers this is not a problem either. Breakers are for protecting from shorts, but there main purpose is to protect the wire from being overloaded. Your 15 amp breakers are protecting 14 gauge wire where as your 40 amp protects the 8 gauge wire.

One 15 amp breaker is probably servicing 6 to 8 outlets say two bedrooms, say each has a tv a clock radio and a light generally 1 to 2 amp draw max.

 

[tidalwave1]

Like mark said just make sure you size your breaker to the proper wire size and you will be fine, grounds are fine the way they are.

 

[Coral Dilema]

Agree with all the above. The breaker is to protect the wires from overheating. That is why you have a minimum diameter wire to be used with a specific size breaker.

As to the slack on the ground wires, I always like a little slack in the wires, never know when you may need to move things around a bit to add another circuit or you may decide to replace the main breaker panel with a larger one and need that slack to connect to the new box. You can always make a wire shorter but its kinda hard to lengthen one

 

[cjm5283]

Also agree with all the above. I would like to add if you are having these kind of questions, although easy to install I would ask for some help from a friend that has done this before to verify proper installation.

 

[Redman88]

as i under stand it most newer boxes can handle any combo of circut breakers as long as no single one exceeds the maximum rating for that box/main breaker

 

[bdr]

First its kind of scary to be saying someone else did it wrong you fixed their work and are asking these questions... that aside all advice so far is correct you say 2 100 amp breakers. do you mean a 2 pole 100 or truely 2 100 amp breakers. I cant say ive seen one like that. (been an industrial construction electrician for 11 years maintenance for 3) Either way its a 100 amp panel. When buying new breakers i cant remember who bought out who siemens or ite so if you ask for a siemens breaker and they dont have one ite is the same or vice versa. your panel has lots of space left for a couple 15 amp circuits for an aquarium. main breaker protects the wires to the pole branch circuit breakers protect the wires to your outlets. all circuits can be rated higher then 100 amps but if they draw a total of more then 100 the main breaker trips to protect your main feeder. grounds touching are fine they all go under the same terminal strip in the end anyways. Leave the wire long if you need to more a breaker when the panel fills up you will regret shortening them. Best advice given so far hire someone licensed.

 

[chatyak]

Thank you to all who responded - helps clears up the obvious. Off to the store now to pick up 14-2 romex along with wires, pvc conduit, and GFI outlets. I plan to pigtail the wires to the romex in a junction box with each outlet being independent... will post pics as I go along.

 

[chatyak]

First its kind of scary to be saying someone else did it wrong you fixed their work and are asking these questions... that aside all advice so far is correct you say 2 100 amp breakers. do you mean a 2 pole 100 or truely 2 100 amp breakers. I cant say ive seen one like that. (been an industrial construction electrician for 11 years maintenance for 3) Either way its a 100 amp panel. When buying new breakers i cant remember who bought out who siemens or ite so if you ask for a siemens breaker and they dont have one ite is the same or vice versa. your panel has lots of space left for a couple 15 amp circuits for an aquarium. main breaker protects the wires to the pole branch circuit breakers protect the wires to your outlets. all circuits can be rated higher then 100 amps but if they draw a total of more then 100 the main breaker trips to protect your main feeder. grounds touching are fine they all go under the same terminal strip in the end anyways. Leave the wire long if you need to more a breaker when the panel fills up you will regret shortening them. Best advice given so far hire someone licensed.

Hired someone to fix it long ago before I was learning myself. I believe it is a two-pole 100, not two diff 100's.... highly doubt it would be as the house is from the 50s.

 

[bdr]

where are you running the pvc pipe?

 

[chatyak]

Here you are:

I think I have an issue with the junction box. It says 18.6 cubic inches - but from what I have read here, the # of wires I have will be greater than that amount.

3 outlets + the romex is = 12 wires

12 wires * 2 = 24 cu in. needed


or am I missing something?

I have single wires of #14 gauge to be used inside the conduit and they will all pigtail to the romex at the junction - then the romex goes to the breaker.

 

[sfsuphysics]

your pigtails should be in the outlet box, not in a separate junction box.

also you don't typically use conduit for Romex (NM) wire. edit: didn't see you were running exposed wires, in which case yes conduit is required. However I would never run NM wire in conduit, instead I'd get stranded wire and pull it.


That said there are levels of anal retentiveness that electricians will have. I had one guy when they hooked up my solar who was super clean with everything, his boss however who was paying him by the hour wanted him to get it done right, and not be so worried that it looks perfect.

 

[chatyak]

I am not using romex inside the conduit. The romex ends at the junction box and pigtails inside there, with the wires coming from each GFI outlet. I haven't heard of pigtailing inside the outlet box itself. I am using individual single wires (red,white,black) of 14 gauge - THHN I believe - made by southwire. I'll have to check the name again.

Regardless though - what size junction box is required to handle this situation?

 

[bdr]

well for box fill you dont count grounds. yes they take up space and you would think they would but they dont. so its only 8 wire they do count the marettes. that being said with that oct box your all good. Pvc pipe indoors is a no no in ontario and is against code. emt (thin wall metal) with rain tight twist on compression fittings are what should be used in this situation. That aside every thing looks good. only one wire per connector into the oct box and you cant use L16s any more on romex. they pretty much all come from china and the screws quite often go through the clamp and into the wire to make a short. need the ones with two screws. #14 thhn is fine


edit i went though my code book and i cant find find where it forbids pvc conduit inside. just working in the trade for the last 14 years ive always just been told its a no no

 

[Paul B]

You can put about a dozen more breakers in that box, forget about the grounds, they are fine.
(electrician 40 years)

 

[chatyak]

well for box fill you dont count grounds. yes they take up space and you would think they would but they dont. so its only 8 wire they do count the marettes. that being said with that oct box your all good. Pvc pipe indoors is a no no in ontario and is against code. emt (thin wall metal) with rain tight twist on compression fittings are what should be used in this situation. That aside every thing looks good. only one wire per connector into the oct box and you cant use L16s any more on romex. they pretty much all come from china and the screws quite often go through the clamp and into the wire to make a short. need the ones with two screws. #14 thhn is fine


edit i went though my code book and i cant find find where it forbids pvc conduit inside. just working in the trade for the last 14 years ive always just been told its a no no

Could you share the math equation for the junction box-fill rule? Just so I understand it properly.

If I have a total of 12 wires (3*3 outlets + 3 romex) but the grounds do not count.... that is 8 wires. So 8 * the standard of 2 (for 14 gauge) would be 16.

Is that correct? Hmmmm that is bad news about the pvc.... now I'm not sure.

 

[chatyak]

You can put about a dozen more breakers in that box, forget about the grounds, they are fine.
(electrician 40 years)

Thank you Paul. I'm still a bit confused about the junction box limit even though BDR explained it.

My understanding was that all grounds together count as one - which would push me over the safe limit for the box. I'll look again to verify the cubic inches, but it seems just shy of what I need. I would feel safer getting a larger box that has no holes in it - and simply drilling my own holes and then siliconing the pvc conduit into it.

 

[Paul B]

Forget the fill capacity of the circuit breaker box. The rules are different for a circuit breaker box than a regular junction or splice box. You are allowed to fill all the spaces with breakers as that is what the panel is designed for. You are not allowed to make splices in there but you can fill it with breakers and their associated wiring as 99.9% of all circuit breaker boxes are. You should see mine. Forget about it.
There are rules for fill in junction boxes (although no one bides by them)
For junction boxes it gets a little confusing. I am also an electrician (retired) in Manhattan, not Canada which may be different. A wire passing through a box counts as one wire but if it is spliced, it counts as two. For my professional advice, I would put the wires in the box that you need, put the cover on the box, go out to dinner and have a nice glass of merlot.

 

[chatyak]

Hi Paul. Thank you for the insight. Sorry to clarify - my question was regarding the PVC junction box I have layed out there on the wooden panel along with my conduit for the outlets. Since this isn't something I do everyday I'd like to be on the safe side.

I was going to go out and replace the octagan junction box with a large square PVC one and drill a hole in the bottom then silicone the bottom conduit piece into it.

No wires will be spliced inside the junction - just 3 hots, 3 neutrals, 3 grounds, being wire-nutted to the hot, neutral, ground on the romex - for a total of 4 wires in each wire nut.

Junction box said 18.6 from what I remember but will check again to verify.

 

[Paul B]

OK, don't silicone anything to the junction box or the new square junction box. (I assume PVC boxes are legal in Ontario) The box you buy has female holes already in it where you connect the conduit. Just buy a box with the size holes already in it for the conduit you are using. They are cheap. You need PVC solvent that you can get when you buy the box.
Besides, silicone does not stick very well to PVC even though many fish Geeks think it does.
For what you are doing I would get a 1900 PVC box which is just a 4"X4" box. You will see the different size holes in it. Get the box for the conduit size you are using and if there are any empty holes in the box, get plugs there to close them.
I can't tell from the picture but you are using either 1/2" or 3/4" conduit.
If you want to use a larger box (which I don't feel you need) you can drill that and buy a fitting that goes on the end of the conduit then that goes into the hole in the box. Don't put any silicone on that. Forget silicone.
If you were here I would give you all that material as I probably have it laying around.