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How hard is it to install NEMA 14-50 by myself?

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How hard is it to install nema 14-50 by myself?
And also, what things should I prepare for it?
The panel are inside the house, but there are already hole on the wall, just wonder how hard is it to do it myself as no experience in those kind of electricity work. But I am a engineer major.
I already bought, 50A breaker, 6/3 nm-b cable, receptacle. Wire cutter already have, screwdriver also.
Been reviewed some Youtube video for how to install it, for me no in the wall wiring requirement, it really looks like plug the breaker in, plug the cable in both cable and receptacle, and done.
The total amp for the board is 100A I think, and there are likely 4 window 6000 BTU AC run at same time at night while charging.
By the way, is UMC water proof?, should I unplug it if in the rain?
 
I ran service to my detached garage in an afternoon. It's no big deal. Make sure the lugs are torqued down right. They'll get really hot if they're loose.

Watch the load on your panel though. 100A is kind of small. Don't forget you can set the current draw on the car. So you can limit it to 25A or whatever to make room for the AC units
 
I ran service to my detached garage in an afternoon. It's no big deal. Make sure the lugs are torqued down right. They'll get really hot if they're loose.

Watch the load on your panel though. 100A is kind of small. Don't forget you can set the current draw on the car. So you can limit it to 25A or whatever to make room for the AC units

Because this is a muti family house, there are a main panel outside the house, and there are disconnect breaker which labeled 100A, and each unit have one, for basement/1st floor and 2nd floor. I guess this means the limit to my 2nd floor is 100A?
 
The work itself is not too hard. Doing it the right way to comply with electric code can be the tricky part, since you (and I) just don't deal with all of the hundreds of rules it has. In this case, I also have a little reservations about just putting in an extra 50 amp circuit into a main panel that's only 100 amp. Have you run a load calculation to see if that is even allowed? I would not want to just do that and have it be an illegal installation. If you aren't allowed to fit a 50 amp circuit, you might want to get a wall connector on a 20 or 30 amp circuit, if that will fit in the calculation.
 
Ok, so it really looks like the work is not hard. Lets discuss it is possible to add 50A breaker in my floor.
The outdoor panel have 3 100A disconnect breaker, for basement, 1st floor and 2nd floor. I live in the 2nd floor, so does this mean my panel have only 100A limit whether how I upgrade it? And consider 4 6000 BTU window AC running at the same time, and probably another 4 computer for 300W each also, is it possible to charge my Tesla also? Or it is not even possible for me to charge at 4 mi/hr?
 
I just installed a circuit couple of weekends ago. The enclosure came with a 50a receptacle which I replaced with a 30a receptacle & breaker since my panel is also only 100A service. I've got 2 x 12000BTU AC units aside from the usual fridge and freezer. My run was only 5' from indoor panel to outdoor enclosure, using 6/3 UF-B cable. Took me about 2 hours. Most of that time (80%) was running the cable and drilling the hole.
 
Because this is a muti family house, there are a main panel outside the house, and there are disconnect breaker which labeled 100A, and each unit have one, for basement/1st floor and 2nd floor. I guess this means the limit to my 2nd floor is 100A?
Beware that in many (most?) jurisdictions it is only legal to do your own electrical work in an owner-occupied single family home. In a multi family home, the work would need to be done by a licensed electrician to be legal.
 
Ok, so it really looks like the work is not hard. Lets discuss it is possible to add 50A breaker in my floor.
The outdoor panel have 3 100A disconnect breaker, for basement, 1st floor and 2nd floor. I live in the 2nd floor, so does this mean my panel have only 100A limit whether how I upgrade it? And consider 4 6000 BTU window AC running at the same time, and probably another 4 computer for 300W each also, is it possible to charge my Tesla also? Or it is not even possible for me to charge at 4 mi/hr?
4 AC plugged into what capacity outlets? Probably 20A each, so how much load do they draw? If they are 20A rated, they could draw 16A each = 64A load, not counting refrigerator and other devices; clearly an overload if you are charging at 40A. Maybe the ACs don't draw that much, but you will have to find out before you do anything else.

I think it would be wise to get a professional to calculate load limits on your panel. Pay for an hour's time and know what is safe, even if you plan to do the install on your own. I use a 10-30 and can charge overnight in 10 hours from 15% SOC.
 
It's free to have an electrician come out and give you an estimate. The higher the estimate, the more likely you will get into trouble if you do it yourself. ;)

Keep in mind, a lot of the cost can be in labor. I asked to contribute my time (labor), and saved a bunch of money. Zero issues with the resulting inspection, and all is working as desired. And, I learned a lot in the process. You will need a cooperative electrician, of course. Not all will do this.
 
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There are load calc spreadsheets on the Internet (some are quite good, seriously), and in some jurisdictions, you can do your own work and have the inspector for your permit (which you still need) inspect it. They will usually go over it with the proverbial fine toothed comb, since you are an amateur. I'm an ex-Electrical Engineer, and have done of wiring job on boats and small stuff on houses, but when it comes to putting in 50 Amp (or a shared 100 Amp circuit in my case, see sig!), I definitely wanted the pros to do it.

Another consideration is that this isn't a normal circuit, it's a high-use, continuous rated draw circuit, so, it's derated to 80% (or overrated 125%, same thing). Another reason to not do it yourself. See the first link in my sig where it says that if the work isn't completely to code (inspected and permitted), many insurance company can use it as an out to not pay on any fire damage. Something to think about!
 
I did it myself and it is not that hard. Of course care must be taken and not sure if you are normally a handy man. So easy for a handy man but if you have not done much of this type of work then call an electrician. It should NOT be $1500 at least not in East TN. Heck even $500 would border on a rip-off.
 
You can do it yourself, but research, research, research. You are asking us questions that we cannot possibly answer. You THINK the panel is 100A. How are we supposed to help with information like that? As you can see from some of the answers, we are all guessing at what you have. Only you can can find out.

So, for the panel your new 50A breaker is on - what is the panel rated at and/or what is the breaker for it? The other 240V loads - look at the serial/model number plate of each unit and read what the amperage draw is of each. You can also buy a clamp on ammeter for $60 or so and measure the current of each of the two legs when all AC units are running to see what the actual panel load is. I too suspect that drawing 40A from that panel is asking too much. It might be better to get a 14-30 adapter from Tesla, install a 14-30 receptacle and then charge at 24A at night. Unless you drive a lot, that should work fine.
 
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Get an electrician or two out for a free estimate, preferably Tesla recommended. They will do a load calc and let you know what will fit your panel and your best wiring options. For example, one of the electricians I had out for an estimate noticed we had an unused 50A cooktop circuit that we could disconnect and use that panel space for the car charger. Both electricians did load calcs that said we could (barely) add a 100A car charging circuit to our panel. I paid one of them to let me keep an "official" load calc.

Then my commercial electrician brother-in-law did most of the work to my specs (all from the HPWC manual). I took care of the city permit and inspection. When Model 3 arrives we'll add a second HPWC sharing the same 100A circuit. No extra panel load, and the wiring is ready to extend over to the other side of the garage.