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NEMA 14-50 install advice

Cyclone

Cyclonic Member ((.oO))
Jan 12, 2015
5,212
1,295
Charlotte, NC
I almost revived this old thread, but went ahead and started a new one and could always ask a mod to collapse it in there if its better served there given the info in that thread. Wire Gauge Size for 50 Amps

I am finally getting around to having a 14-50 added in the garage so I can get off 119/120v charging. I got a quote from an electrician another Tesla owner used for $400 to switch some circuits in my panel to make room for a 50 amp GFCI breaker. The electrician would then run 6 gauge aluminum about 25 feet from the panel in the basement upstairs to the garage. The kitchen is directly above the basement panel and the kitchen and garage share a wall.

I was half tempted to go ahead and run Romex 6-3 NM-B through so an electrician only needs to create the receptacle box and add in a new breaker at the panel, but I'm confused on that process for running that through conduit (or not) because the basement is finished in on the walls with an exposed ceiling and the garage is finished in on the wall the cabling would run up (but exposed on the wall the outlet would be installed on, so wiring would run along beam where wall/ceiling meet alongside the current 120v run). The existing circuits for 120v 15amp outlets in the garage and the exterior lighting + outlets runs up the same wall.

Anyways, he said 6-gauge aluminum is fine for my run, but I thought to ask here. He also stated I would not need a permit, so I thought I would ask here for a second opinion. I've had bad luck with electricians multiple times in the past, so I'm concerned. What do you all think?
 
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A few notes:

You don't need a 50A GFCI breaker for a 14-50 if you don't want to place it in there. It provides some safety for you but is not required.

NM/Romex cannot be exposed where subject to damage. If running within your finished walls, you'll be fine without it and it can be exposed in the ceiling (unless local code prohibits, mainly Chicago and some NY jurisdictions). If you want to run it on the surface, you'll need to "sleeve" it in EMT (thin conduit) up to about 7' off the ground, then it can exit that conduit and run exposed through the joists. #6 should not be affixed to the bottom of the joists, but instead should be run in drilled holes.

If your jurisdiction requires permits, it likely will require one - anything beyond replacing a receptacle or switch generally does. Call your municipal or county inspector, depending upon which one applies, and ask (or look it up).

#6 aluminum is fine. I prefer copper for #6 because it's not that much of a price difference and is easier to obtain.
 
I explicitly asked him about copper. He said it would be "twice as much". I didn't however, clarify if that was $800 or twice as much for a specific component. FlasherZ, honestly, I trust your advice more than his. He did say "technically, code says I should put a GFCI on this, but some people don't". He said that breaker is near $100.

Part of me would be happy to find another electrician that would give me a written quote rather than verbal, but after 3 electricians coming to look at the job, this is the only one that ever followed back up!
 
I explicitly asked him about copper. He said it would be "twice as much". I didn't however, clarify if that was $800 or twice as much for a specific component. FlasherZ, honestly, I trust your advice more than his. He did say "technically, code says I should put a GFCI on this, but some people don't". He said that breaker is near $100.

Part of me would be happy to find another electrician that would give me a written quote rather than verbal, but after 3 electricians coming to look at the job, this is the only one that ever followed back up!

Code only requires that for 120V/15-20A circuits in damp/wet areas (kitchen, laundry, garage, outdoors, etc.) and/or swimming pools/hot tubs. It is NOT required by code, technically or otherwise, for larger circuits - not even outdoors. Now, *should* it be? I would support GFCI protection for RV outlets outdoors as a member of the CMP's, but not sure it'll happen for the next few cycles. $100 cost on those breakers tends to sway public opinion. :)

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Part of me would be happy to find another electrician that would give me a written quote rather than verbal, but after 3 electricians coming to look at the job, this is the only one that ever followed back up!

That's the nature of residential electricians. Many of them will come look at a job, but will happily GTFO if it looks like it's going to be difficult/complex. If it's just a matter of punching a hole through a wall and mounting a box, they can milk that for profit.
 
I explicitly asked him about copper. He said it would be "twice as much". I didn't however, clarify if that was $800 or twice as much for a specific component. FlasherZ, honestly, I trust your advice more than his. He did say "technically, code says I should put a GFCI on this, but some people don't". He said that breaker is near $100.

Part of me would be happy to find another electrician that would give me a written quote rather than verbal, but after 3 electricians coming to look at the job, this is the only one that ever followed back up!

FlasherZ is the expert here, but I have never seen a 14-50 on a GFCI. 50 Amp feeds to a hot tub need a GFCI, but not a 14-50. There may be some confusion about a garage location where GFCI's are needed for 15 and 20 Amp outlets. BTW, the Tesla UMC as well as the HPWC have GFCI's built in.

As a point of reference a Siemens, 50-Amp, GFCI circuit breaker is $60 on Amazon, but the non-GFCI is $10.
Siemens QF250 50-Amp 2 Pole 240-Volt Ground Fault Circuit Interrupter - - Amazon.com
Siemens Q250 50-Amp 2 Pole 240-Volt Circuit Breaker - - Amazon.com
 
NM/Romex cannot be exposed where subject to damage. If running within your finished walls, you'll be fine without it and it can be exposed in the ceiling (unless local code prohibits, mainly Chicago and some NY jurisdictions). If you want to run it on the surface, you'll need to "sleeve" it in EMT (thin conduit) up to about 7' off the ground, then it can exit that conduit and run exposed through the joists. #6 should not be affixed to the bottom of the joists, but instead should be run in drilled holes.

So, if I am understanding correctly, I can use Romex through drilled holes in the wooden beams along basement ceiling (holes already there from other wiring), and I'd be fine running behind the finished walls to ceiling of garage (yay, no need to rip open the drywall and staple the Romex to the joists), but then I can't run the Romex over the front or bottom surface of the wooden beam running across the top of the garage at the ceiling? Instead, I would have to run it slightly below and drill through the joists?

This photo is not the wall where the outlet would go, that wall is behind the Tesla in this pic. However, it has the same beam across the top and has the current orange wiring stapled to it.
guJMWbo.jpg


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That's the nature of residential electricians. Many of them will come look at a job, but will happily GTFO if it looks like it's going to be difficult/complex. If it's just a matter of punching a hole through a wall and mounting a box, they can milk that for profit.

Yeah. Meanwhile, during the kitchen remodel, the remodelers had to switch electricians when one just left and didn't return. He said the circuit was overloaded on that run when they put the microwave over the stove and just left. They hired a different guy to run a new circuit for that and the disposal. A different person came and installed a motion light in the back corner of the house and the light flickers and drips water out of it. Never came back to fix whatever weatherproofing it needs -- though, he never came back to get paid in the first place either.

This is why sometimes I am tempted to do the work myself, not because I am trying to be cheap, but because I'm willing to actually do the work to get it done right!
 
I explicitly asked him about copper. He said it would be "twice as much". I didn't however, clarify if that was $800 or twice as much for a specific component. FlasherZ, honestly, I trust your advice more than his. He did say "technically, code says I should put a GFCI on this, but some people don't". He said that breaker is near $100.

Part of me would be happy to find another electrician that would give me a written quote rather than verbal, but after 3 electricians coming to look at the job, this is the only one that ever followed back up!

6-3 nm-b is only $2.79 a foot at home depot, which is practically the most expensive place to buy it. If he wants to charge twice $800 for that, you should probably look for a new electrician.
 
6-3 nm-b is only $2.79 a foot at home depot, which is practically the most expensive place to buy it. If he wants to charge twice $800 for that, you should probably look for a new electrician.

And HD is where I priced it out for doing it myself. About $70 for the wiring. Charlotte has a $64 permit fee for Homeowners doing their own electrical work. I'd still come out ahead! But the price isn't as big of a deal as doing it right! But I suspect the $400 wouldn't be double because part of the quote's costs is to "make room" in my panel because there is no open space now and about 1/3 of my breakers are already half-height.
 
Apologies for the partial thread steal, but since we're talking about residential electricians and requiring a permit. I'm curious, what happens if the electrician doesn't apply for a permit (and therefore doesn't get it inspected?) Who's on the hook when something goes wrong? Is it the home owners responsibility or the electrician to get the permit and have it inspected?
 
Apologies for the partial thread steal, but since we're talking about residential electricians and requiring a permit. I'm curious, what happens if the electrician doesn't apply for a permit (and therefore doesn't get it inspected?) Who's on the hook when something goes wrong? Is it the home owners responsibility or the electrician to get the permit and have it inspected?

Well, I don't know about the permit, but I read that some electricians are allowed to self-inspect. Now, I cannot recall if I read that about rules here in Charlotte, or just a general thing about "some jurisdictions". But I would be interested in hearing other responses to this as well!
 
So, if I am understanding correctly, I can use Romex through drilled holes in the wooden beams along basement ceiling (holes already there from other wiring), and I'd be fine running behind the finished walls to ceiling of garage (yay, no need to rip open the drywall and staple the Romex to the joists), but then I can't run the Romex over the front or bottom surface of the wooden beam running across the top of the garage at the ceiling? Instead, I would have to run it slightly below and drill through the joists?

I had to go back and look at my code book. :)

Yes - fishing cable behind finished walls is legal without attaching the cable to the studs, if the wall already exists. And after looking some things up in the code, it will be legal for you to run along this beam. The restriction I was thinking of is in basements and crawlspaces is for smaller than 2 #6 conductors, but because you'd use 6/3 NM cable, it may be attached to the bottom of joists without a problem. And since this is a garage, you're fine. My preference would be to take it in the attic and drill through the top wall-plate to send the cable down, if you can do that, less potential for damage.

This is why sometimes I am tempted to do the work myself, not because I am trying to be cheap, but because I'm willing to actually do the work to get it done right!

It's tough. I'm the type that prefers good conduit work with appropriate sweeps and angles. Some electricians go as cheap as they can and use FMC or liquid-tite and don't care how the conduit looks.

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Apologies for the partial thread steal, but since we're talking about residential electricians and requiring a permit. I'm curious, what happens if the electrician doesn't apply for a permit (and therefore doesn't get it inspected?) Who's on the hook when something goes wrong? Is it the home owners responsibility or the electrician to get the permit and have it inspected?

Generally, licensing laws determine this. In Illinois and Missouri, there is no licensing of electricians. In Virginia, there is state licensing of electricians - and if an electrician fails to get a permit and have something inspected when required, he/she risks losing the license in a disciplinary hearing and a fine of $10,000. I outlined it here: FAQ: Home Tesla charging infrastructure QA - Page 23 . Typically, an electrician's agreement says they will obtain any necessary permits and inspections and the homeowner can use that contract as a reliance upon them for the service.

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Well, I don't know about the permit, but I read that some electricians are allowed to self-inspect. Now, I cannot recall if I read that about rules here in Charlotte, or just a general thing about "some jurisdictions". But I would be interested in hearing other responses to this as well!

I've found it very rare that electricians are allowed to self-inspect their own work. I have seen where electricians are permitted to inspect homeowners' work, but never their own. Bottom line - every jurisdiction is different. Contact your local (municipal or county) building office and ask what's required.
 
I had to go back and look at my code book. :)

Yes - fishing cable behind finished walls is legal without attaching the cable to the studs, if the wall already exists. And after looking some things up in the code, it will be legal for you to run along this beam. The restriction I was thinking of is in basements and crawlspaces is for smaller than 2 #6 conductors, but because you'd use 6/3 NM cable, it may be attached to the bottom of joists without a problem. And since this is a garage, you're fine. My preference would be to take it in the attic and drill through the top wall-plate to send the cable down, if you can do that, less potential for damage.

The garage has pull-down steps and a standing room attic that I keep our Christmas decorations and large empty boxes (tv, computer, etc.) in. I can definitely run it through there to not be exposed at all and then run just a straight line down into the garage. Assuming I can run the Romex over the joist for this run straight to the plug, I would be covered the entire way.

This may be how I go about doing this. At least I would know the right wiring was used and b/c of the kitchen remodel, I know exactly which spot to run fishing wire through to help guide the Romex through.

Sadly, I do not have a picture of my panel readily available (maybe one tonight once I get home). Otherwise, I would be asking if this looks doable for me. The reason I started down the path with an electrician was because I thought I would need a sub-panel. But this one said no sub-panel would be needed - just need to make room in the existing panel. And I also learned that I have 200 amps of service at the house. So it wasn't a completely worthless visit!
 
I explicitly asked him about copper. He said it would be "twice as much". I didn't however, clarify if that was $800 or twice as much for a specific component.

Copper wire costs twice as much as aluminum. Roughly $2/ft vs $1/ft for 6-3 w/gnd. So if your run is 50 feet, a $50 difference. Labor should be about the same for either and is likely the vast majority of the cost.

Copper is worth it in my opinion. my house, built in 1975, was wired with a mix. a lot was built sloppily, and I got trouble with both, but more with the Aluminum. I've put contact grease on all the connections that seemed to be giving trouble (including in the breaker box, which has aluminum bus bars) and that's helped.

--Snortybartfast
 
The garage has pull-down steps and a standing room attic that I keep our Christmas decorations and large empty boxes (tv, computer, etc.) in. I can definitely run it through there to not be exposed at all and then run just a straight line down into the garage. Assuming I can run the Romex over the joist for this run straight to the plug, I would be covered the entire way.

If there is likely to be traffic in the attic to get at stored items, you would do well to put down at least a 1x2 across the joists next to the Romex to protect it from damage from stuff being moved around or from feet.

The mention of running "Romex over the joist for this run straight to the plug" is confusing to me. Will the plug be in the ceiling?
 
The mention of running "Romex over the joist for this run straight to the plug" is confusing to me. Will the plug be in the ceiling?

Look back at the picture in post 7. The wall behind the Tesla is where the outlet would be. But the wall in the pic (beside the Tesla) has a light switch in the middle of the wall (for the exterior motion lights) with the wire for it coming down from the attic along the face of that wooden beam. This is what I am talking about doing against the back wall for the bit of wiring run from the attic down to the receptacle.
 
Cyclone: regarding doing the work yourself: I wanted to do to the work myself too, I'm big on DIY stuff, and bugged Flasherz with a thousand questions. Parts + permit would have cost me (HD prices) about $250-$300.

In the end, the electrician charged me $395 for the job (our agreed upon price), but what I thought would be a 1-2 hour job, took two guys 3.5 hours. I have no idea what took so long or how he made any money, but that's not my problem either. I'm glad I didn't do it myself.
 
I'll give the electrician a call tomorrow about using a non-GFCI circuit and using 6-guage THHN or 6-3 NM-B Romex. As was pointed out by snort, even if the wiring is double the cost, I'm only using about 25 feet and with the switch to a non-GFCI circuit, this should be a net reduction in price.

I also have to call the city and ask if this job would require a permit.
 
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Code only requires that for 120V/15-20A circuits in damp/wet areas (kitchen, laundry, garage, outdoors, etc.) and/or swimming pools/hot tubs. It is NOT required by code, technically or otherwise, for larger circuits - not even outdoors. Now, *should* it be? I would support GFCI protection for RV outlets outdoors as a member of the CMP's, but not sure it'll happen for the next few cycles. $100 cost on those breakers tends to sway public opinion. :)


I'll throw in against GFCI. I've noticed these devices are powerhogs. Both the breaker and the outlet types. You get a house full of them and you get a constant background draw, for no reason. I even test tripped a whole bunch of outlets that don't get used, and they still draw power. As long as the outlet is high enough so the UMC can't be in standing water I think it's fine because the UMC has GFCI built in.
 
I'll throw in against GFCI. I've noticed these devices are powerhogs. Both the breaker and the outlet types. You get a house full of them and you get a constant background draw, for no reason. I even test tripped a whole bunch of outlets that don't get used, and they still draw power. As long as the outlet is high enough so the UMC can't be in standing water I think it's fine because the UMC has GFCI built in.

They use power, but I would not call them power hogs.

http://forums.jlconline.com/forums/forum/jlc-online-expert-forums/the-electric-shop/49110-afci-gfci-power-consumption shows at least one example where GFCI's draw 0.6 Watts each and AFCI's draw 2 Watts each.

I may have become numb from the Tesla Vampire drain, but 0.6 Watts per GFCI does not seem too piggish...