One bus bar in Subpanel

[desert4wd]

It's been a little while since I've done circuit breaker work so I picked up a home wiring book yesterday. After comparing pictures/notes I came to the conclusion I didn't understand what I was seeing from my own subpanel . I have both ground and neutral wires going into one bus bar- what gives? What can you tell me about this picture?

Digressing, I'm in a "new" place. The main breaker panel is strange enough, but in any case, it has two 30A feeder breakers that go 150' down to the shop. The subpanel has a double "sub" main breaker. All this is a bummer because I was hoping to add 240V at 50A for a welder before I finish the walls. Perhaps the Hobart Handler 187 or something equivalent. 30 amps appears to be borderline but unless I have separate power strung up or dig a new line, that's what I have to work with. - - Thanks for your comments.

 

[sneezer41]

neutral is ground, but yet is not ground........anyway, they are tied at the box

 

[Junkman]

Re: One bus bar in Sub panel

neutrals and grounds are only separated on sub panels based on the old code. Don't know how they are treated in the 2008 NEC code book. When the panel requires a separation of grounds and neutrals, you purchase another buss bar to install into the panel on the left side.

 

[Tscott]

As the others have said Neutral is ground. There is no effective difference in the two. The neutral is designed to carry current to the bus bar in the main panel whereas the ground is nothing more than a safety measure in the event there is a short of some type. This holds true in high voltage as well. If you have a power pole near by you will notice a copper wire running up the pole and connecting to one of the wires suspended from the pole. The suspended wire is effectively the neutral and the copper wire on the pole in a "Pole Bond" AKA ground. All this system does is to limit potential differences between the neutral wire and the ground.

Tom

 

[desert4wd]

Thanks everyone for your comments and information, and for clearing that up. It just struck me as a strange arrangement because I hadn't seen it before. Again, I appreciate your help.

 

[mt05450]

Is it legal to splice inside the sub-panel? Someone please clarify.

 

[aarcuda]

in the panel, it shows that you are feeding the panel bus by connecting the supply to the 30 A breaker's load side (ie the panel supply goes into the goes outtas) instead of going into a main breaker that connects to the terminal lugs from the breakers. (or by connecting the supply directly into the supply lugs on the breaker buss)

is that legitimate?

 

[porcupine73]

A couple things I see that triggered memories of some things I think I saw in NEC.....
1. That sub panel in the pic appears to be an MLO (main lugs only). Your incoming power is supposed to go to the lugs right above that 2-pole braeker. What is being done in that pic is backfeeding the power through the 2-pole breaker onto the bus. I think that is allowed, but it is supposed to be bolt on breaker for that purpose, not just a snap on.

2. AFIAK in the system, ther eis supposed to be only ONE point where the neutral is bonded to the ground. All sub panels are supposed to have a separate neutral bar and separate ground bar and may require a ground rod at the out building too. Maybe that changed in the 2008 NEC I haven't gotten my copy yet. I am pretty sure i saw in 2008 NEC that all outlets in garages etc now require GFCI the only exception now I think is fire alarms.

3. What size cable is that coming into this sub panel? Is it going to be good for the 50 amps for a welder?

 

[aarcuda]

A couple things I see that triggered memories of some things I think I saw in NEC.....
1. That sub panel in the pic appears to be an MLO (main lugs only). Your incoming power is supposed to go to the lugs right above that 2-pole braeker. What is being done in that pic is backfeeding the power through the 2-pole breaker onto the bus. I think that is allowed, but it is supposed to be bolt on breaker for that purpose, not just a snap on.

2. AFIAK in the system, ther eis supposed to be only ONE point where the neutral is bonded to the ground. All sub panels are supposed to have a separate neutral bar and separate ground bar and may require a ground rod at the out building too. Maybe that changed in the 2008 NEC I haven't gotten my copy yet. I am pretty sure i saw in 2008 NEC that all outlets in garages etc now require GFCI the only exception now I think is fire alarms.

3. What size cable is that coming into this sub panel? Is it going to be good for the 50 amps for a welder?

thats exactly what I thought too. separate breaker which is bolt in and not back fed. Separate ground bus with a ground rod outside the shop, and will the cable to the shop support 50 Amps

 

[desert4wd]

Thanks a bunch. Everything I've seen/read here is making things clearer. I appreciate the help I got as PM's also.

The wire sez - "8 Type THW OR MTW 600V E14656K UL" It didn't have CU marked on it, but it is. It should be good to go for a 40A / 240 circuit which boosts the welder possibilities a little.

I don't have a clue to why this box is wired as it is. Perhaps the service wires were cut too short in the beginning?- lol. Anyways, I see a little box re-arranging in the near future.

 

[porcupine73]

Is it just me or does that white/neutral wire coming in look like a smaller gauge than the incoming black leads going to the 2-pole breaker?

hehe yah who knows why the box is wired like that; I have seen some strange things like that myself. It's kind of late now but if it is because the incoming leads were too short, I think many of those boxes you can flip the other way around to feed from the bottom?

 

[porcupine73]

Also in the pic, at the bottom, to the left of where the incoming wires are, near the knockout, it appears the black wire insulation is stripped or missing near that yellow tape or whatever that is?

 

[sneezer41]

Yeah, my first post I was assuming that this was your panel with the breaker going out to the subpanel. I would not see the breaker business as dangerous per se, as long as there was an appropriate breaker on the other end. I think others are right, that ground and neutral float on subpanels

 

[dipper]

didn't see an answer to your question about splicing inside the panel box, but
yes it is allowed by NEC code.

 

[Aceman]

This subpanel looks fine to me. There is nothing wrong with running a 3 wire feed(2 hots, neutral) although I believe the 08 code just changed that to requiring a 4 wire feed.

You DO NOT have to use the lugs at the top of the panel, as long as you're using a breaker with a hold-down device. See the screw through it?

 

[Charles (in GA)]

This subpanel looks fine to me. There is nothing wrong with running a 3 wire feed(2 hots, neutral) although I believe the 08 code just changed that to requiring a 4 wire feed.

You DO NOT have to use the lugs at the top of the panel, as long as you're using a breaker with a hold-down device. See the screw through it?

Code does require the hold down device to be approved by the panel/breaker manufacturer (408.36(F)) and that screw may very well be the approved retention method.

Charles

 

[desert4wd]

Well...- lol. It's good to have several pairs of eyes looking at this thing. It appears to be just as interesting as when I first posted it. I'm not in the garage, so I'm looking at the original photo. 1.) The neutral/white wire doe's appear to be smaller, but it also looks like it's wrapped "around" in the white sheathing. (Picture wrapping a wire with electrical tape except white). 2.) The yellow is the sheathing of one of the cables going out and the wire insulation is ok- the photo resolution isn't that terrific and probably isn't helping. 3.) There are also two 30A breakers in the main panel for the cables going down to the shop. 4.) Thanks for the clarification on the splicing and the hold down device. 5.) I should have labeled the "incoming" breaker- sub main. At that point, I was still scratching my head. Whoops.


I'm going out tomorrow or the next day (asap) and will shut things down, cut the drywall opening for a 240V receptacle and I'll dive into all that's going on a little more.
Thank you.

 

[Junkman]

Re: One bus bar in Sub panel

Well...- lol. It's good to have several pairs of eyes looking at this thing. It appears to be just as interesting as when I first posted it. I'm not in the garage, so I'm looking at the original photo. 1.) The neutral/white wire doe's appear to be smaller, but it also looks like it's wrapped "around" in the white sheathing. (Picture wrapping a wire with electrical tape except white). 2.) The yellow is the sheathing of one of the cables going out and the wire insulation is ok- the photo resolution isn't that terrific and probably isn't helping. 3.) There are also two 30A breakers in the main panel for the cables going down to the shop. 4.) Thanks for the clarification on the splicing and the hold down device. 5.) I should have labeled the "incoming" breaker- sub main. At that point, I was still scratching my head. Whoops.


I'm going out tomorrow or the next day (asap) and will shut things down, cut the drywall opening for a 240V receptacle and I'll dive into all that's going on a little more.
Thank you.

Wrapping a black wire with white tape to identify it as the neutral / ground wire is a common electrical practice. The Romex that is yellow indicates that it is a 14 gauge wire. I don't know all the new color codes, but all Romex being manufactured today, is color coded as to its wire size. That way, you know the wire size at a quick glance. Makes you wonder why it wasn't done 30 years ago...

 

[porcupine73]

Oh yah there is a screw holding down that breaker, it was hidden in plain sight.

Interesting. I have some yellow nm-b, not sure if it's romex brand, I bought maybe two years ago at the despot that is 12awg. That was right around the time they started selling that orange colored as well, though I don't recall seeing the orange recently......

 

[Charles (in GA)]

Re: One bus bar in Sub panel

The Romex that is yellow indicates that it is a 14 gauge wire. I don't know all the new color codes, but all Romex being manufactured today, is color coded as to its wire size. That way, you know the wire size at a quick glance. Makes you wonder why it wasn't done 30 years ago...

Current Southwire manufactured Romex I see in Lowes and HD that is yellow sheathed is 12 gauge. Not sure about the other sizes.

Charles

 

[CalGeo]

White sheathing = #14 thhn
Yellow sheathing = #12 thhn
Orange sheathing = #10 thhn

They may also be rated as thwn, which is good for wet locations @75 degrees Celsius. Thhn is good for dry locations @90 degrees Celsius. Both are good for oil locations. I believe the change in color was for simpler inspections and easy identification.

 

[rburke65]

If you wanted to attach the #8's to the lugs, you could remove the 2 mounting screws on the "guts" rotate 180 degrees and reinstall. This would put your lugs at the bottom of the panel, and the the #8's would be long enough. The cover should even fit without rotating it.

 

[desert4wd]

Thanks for that suggestion. I pondered that earlier but didn't know for sure I could do that until looked at the unit again.

*The wrapped neutral wire is a #10 so it looks like I'm back to square one. Maybe square two since I know what's going on now- haahhaha.

 

[desert4wd]

OK. Maybe I should do a little more research before asking this question, but what the heck.
So I have 40A service to the sub panel and I'm interested in something like the Miller 180 or 212 welders. (I think I'm pushing my luck here but...?) The Miller plug looks like a NEMA 6-50 but I what I'm curious about is that I've read that a/the sub panel needs four conductors. How is this arrangement possible while still using the NEMA 6-50 and how would the wires be situated? Advice, comments, warnings appreciated!

 

[zj96sc]

i'd stick with the 200 series welders, and between lincoln and miller, i say miller. I've got a lincoln 175, and I think you'll be happier the long run with a miller, and a 200 series. even though the 180 and 212 are both "220" welders, they are not even close to being in the same category....if the price didn't give it away.

you just need a hot/hot/ground to wire up a 6-50


newb question...how can that panel 'safely' run 120 with a neutral wire smaller than the hot wire?

 

[desert4wd]

Thanks for pointing me in the right direction with the welders and 6-50 hook-up. I've been eye-balling the Miller 212 , but don't want to actually over extend the max. amps (40)

Yesterday I talked with a local "reputable" electrician and he said no worries with the smaller neutral, at least when it comes to 220V. As far as 120V, I don't see why not, since the hots are #8 and the neutral is#10 wire powering regular 20A and 15A breakers. Some of the other folks here have the math on this I'm sure. I might also add here that I don't have any high-draw equipment.

Today I visited a local Welding store- AirGas- and at first the guy was hesitant about me having 40 amps to work with (gotta have 50A) but he came around after a minute and started promoting the 220 Welders.
Thanks.

 

[RoscoeJ]

Is it legal to splice inside the sub-panel? Someone please clarify.

You cant" shave" the wire and wrap new wire arround it. They used to do this with the old knob and tube . You can join two wire together in the panel , but is seldom done. What do you have, to splice into in the panel box?

 

[zj96sc]

is 40 the best you can do with #8 over 150'? I dont know the size:distance numbers.

what kind of work are you going to be using the welder for?

 

[desert4wd]

Going by a wire size/capacity/use chart, that is what I'm limited to. Increased resistance over the 'longer' distance will lower that figure also. I looked on the net for a decent photo, but couldn't find one. You may want to give it a search.

I have a number of different home and Jeep fabrication projects (brackets/skids etc) plus various repairs in mind. If your young and don't have one, my advice is to add a good welder to your arsenal of tools early- you wont regret it . I've spent too many years bolting metal together- lol.

 

[eljefino]

Have read you can "cheat" the needed wire size/ampacity with welders due to their intermittent nature.

My lincoln buzz box has either 10 or 12 (eek) gauge wire in its own pigtail, but the 50 amp plug.

Also plug sizes/ampacity is only "approximate" in 220 land, odd, wierd.

My garage is wired with 3 conductor, 8 gauge, plus ground. 40 amp breaker feeding the sub-box and another 40 amp feeding the welder plug. A seperate 110/20 amp line feeds the lights. Would hate to be welding, catch something on fire, and have the lights go out all at once.

 

[Junkman]

Have read you can "cheat" the needed wire size/ampacity with welders due to their intermittent nature.

My lincoln buzz box has either 10 or 12 (eek) gauge wire in its own pigtail, but the 50 amp plug.

Also plug sizes/ampacity is only "approximate" in 220 land, odd, wierd.

My garage is wired with 3 conductor, 8 gauge, plus ground. 40 amp breaker feeding the sub-box and another 40 amp feeding the welder plug. A seperate 110/20 amp line feeds the lights. Would hate to be welding, catch something on fire, and have the lights go out all at once.

The glow of the flames will help you find the exit...

 

[desert4wd]

Ha, I was thinking the same thing exactly- lol.

The shop here is now wired up for 40A.

I haven't read or heard anything directly about the cheating/intermittent theory because this is a rather new development for me, but I've been thinking about it , duty cycle in mind.

 

[zj96sc]

I'd get the 212 welder and do what you've gotta do to get the wiring to handle it. You're also not going to be operating the welder at max current all that often either. I've got a 30amp on my 175 and have never popped it. I started primarily on jeep fabrication, and now moved to full out chassis fab and kind of wish i had the bigger welder. If you're anything like me, you'll end up tubing out yer jeep too....hehe

Paul

 

[desert4wd]

Ya, I'm kind of falling in love with the 212. But I do that with a lot of equipment- lol. We'll see about tubing the Jeep. It's possible though. Or should I say, it will be possible now.

 

[desert4wd]

This thread started originally because I wanted to get a 230v welder. I finally did buy one last week and it's a Miller 180. The decision was primarily based on the $$ available. Anyways, I lit it up last night after getting the associated requisite gear and all is well.... except for my ability to MIG weld perhaps- ha. Anyways, it appears success is at hand. What ever money I saved by buying a smaller unit is now being spent on more welding/metal work stuff. (No one told me!- hahahaa) Just kidding. Grinders, clamps, safety gear. Next the drill press and a dry saw- if I can afford one. In conclusion, I'm a happy camper with lots of projects.