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Wire size for wall charger

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Curious why you are not using MC wire as no conduit would be required.
I like the look (clean) and structure of EMT conduit and I have installed several thousand feet of it in the past 30 years so the labor is not that big a deal. It makes a good ground and protects the wire very well. I only use MC wire or flexible conduit for short runs where the flex is needed. Like motor hookups where there might be a bit of vibration. And I am a perfectionist and MC runs generally look sloppy and temporary to me. Like I didn't have time to do it right. 😀
 
Great discussion everyone; I've (mostly) read the thread and learned some great info here.

I'm having a gen 3 Tesla charger installed soon and I would like to have it charge at the max capacity. I've requested a 60A breaker and will keep an eye out for the wiring that will be used by the installer.

My questions is: are any of you familiar with the Canadian codes? I'm assuming that there is similar language in that Romex 6/3 is not allowed and Romex 4/3 NM-B gauge wiring is required to achieve desired charging amperage of 48A.

Thanks!

*edit*

Of course I go and read another thread and see this post (post #28):


My understanding is that this installation is incorrect (60amp, hardwired in, 6 AWG )?
 
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Of course I go and read another thread and see this post (post #28):

My understanding is that this installation is incorrect (60amp, hardwired in, 6 AWG )?
Sigh. No. That installation IS proper and correct. This is why it is really really REALLY important to ALSO specify what wire type people are talking about and NOT just the wire gauge. You hear people shouting loudly to not use 6 gauge Romex for 60A circuits, because it is only rated for up to 55A. And that is true. But that installation you linked to is using 6 gauge individual wires in a conduit, and 6 gauge of that type is rated for up to 65A, so it is proper for a 60A circuit. Here is an ampacity table that shows this:

Look at the first column, which is Romex, and then the second column, which is the wire in conduit.
 
Sigh. No. That installation IS proper and correct. This is why it is really really REALLY important to ALSO specify what wire type people are talking about and NOT just the wire gauge. You hear people shouting loudly to not use 6 gauge Romex for 60A circuits, because it is only rated for up to 55A. And that is true. But that installation you linked to is using 6 gauge individual wires in a conduit, and 6 gauge of that type is rated for up to 65A, so it is proper for a 60A circuit. Here is an ampacity table that shows this:

Look at the first column, which is Romex, and then the second column, which is the wire in conduit.

Gotcha, thanks. I assumed Romex which was my mistake.

Thanks again.
 
Gotcha, thanks. I assumed Romex which was my mistake.
Well, yeah, the person who posted it didn't specify either way in the text of the post, which was irritating, but I clicked into the pictures to look at the wall connector mounted between the garage doors, and you can see the grey conduit coming across the wall and then down into the wall connector with those little metal clips attaching it to the wall.
 
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Sigh. No. That installation IS proper and correct. This is why it is really really REALLY important to ALSO specify what wire type people are talking about and NOT just the wire gauge. You hear people shouting loudly to not use 6 gauge Romex for 60A circuits, because it is only rated for up to 55A. And that is true. But that installation you linked to is using 6 gauge individual wires in a conduit, and 6 gauge of that type is rated for up to 65A, so it is proper for a 60A circuit. Here is an ampacity table that shows this:

Look at the first column, which is Romex, and then the second column, which is the wire in conduit.
My Model S pickup appointment is next Saturday Dec 18 so I spent my spare hours this weekend planning and installing my gen 3 Wall Connector. I finished the 3/4" EMT run this weekend. It is a nice clean run, about 40 feet with three - 90 degree bends.

I just returned from Home Depot with the THHN wire. I'll pull it when I get time later in the week. I bought 50 feet AWG#6 red, 50 feet AWG#6 black, and 50 feet AWG#10 green. This is 90 degree Celsius wire and is rated at 75 amps. It is the Cerrowire from your chart. #6 was $1.18 a foot, #10 was $0.54 a foot. I also bought 4 wire hangers for the conduit. $161.34 total including tax. My total materials investment for the install is about $250 including the 60 amp Square D breaker, conduit, and fittings. Permit not required and I have the experience so I am not using an electrician.
 
Huh--really? I know there are many different colors of wire you can use for hot lines, but I thought there would be some provision in code that you can't have the same color for both sides of a circuit.
That would be news to me. Please let me know if you find a code reference forbidding L1 and L2 both being black. I'm always looking to learn more; your advice on these forums has been very helpful.
 
That would be news to me. Please let me know if you find a code reference forbidding L1 and L2 both being black. I'm always looking to learn more; your advice on these forums has been very helpful.
Yeah, I said "I thought" because I wasn't sure about that but was guessing. However, I did just go do some Googling for code sections, and I think I have found the section that specifies that. It's a section for designating ungrounded conductors in a branch circuit, which means hot wires.

It's 210.5(C)


(1) Branch Circuits Supplied From More Than One Nominal Voltage System
Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit shall be identified by phase or line and by system voltage class at all termination, connection, and splice points in compliance with 210.5(C)(1)(a) and (b). Different systems within the same premises that have the same system voltage class shall be permitted to use the same identification.
(a) Means of Identification. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means.

(b) Posting of Identification Means. The method utilized for conductors originating within each branch-circuit panelboard or similar branch-circuit distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment. The label shall be of sufficient durability to withstand the environment involved and shall not be handwritten.

----------------------------------

Specifically look there in (1) (a). It lists four possible ways of identifying, and the first one says "separate color coding". There is a list I have seen somewhere before of allowed colors for ungrounded conductors, which includes black, red, orange, blue, and some others, but I think this place saying "separate color coding" means that they do need to be two different color wires for the different wires in the circuit.

But that's if you are relying on just the wire insulation color. The next methods listed are "marking tape" and "tagging". So I think you could go ahead and use black insulated wire for both, but then you would need to pick one and mark it with red tape or something at every end or junction point to mark which one is being used as NOT black.

So I think that's my best guess. You can't leave them looking exactly alike, so either the colors need to be different or need to mark one to show it's different. The (b) section seems to be about how if you needed to use some system of marking or identifying that wasn't the obvious black/red, then you need to leave a printed legend explaining what the markings are.
 
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We must have some lawyers here. I try not to read the code books but then I am not a lawyer nor an electrician by trade.

I pulled the wire this morning. I had 40+ feet of EMT and my metal fish tape reel is only 25 feet. I own a 75 foot fiberglass tape reel but could not find it and didn't want to spend $75 to $100 for another one. My plan was to fill the conduit with zip line and use that to pull the wire. So without a fish tape I used the AWG#10 ground wire and pushed it through the conduit. It worked like a charm. I had to wiggle it a bit when it hit the bends but it was pretty easy.

Then I taped the zip line to the ground wire and pulled it back out so the zip line was now inside my EMT ready to pull my wires. I had some 2 inch electrical tape handy that I used to tape the red AWG#6 to the zip line. The a bit lower I tapped the black, then a bit lower I taped the green ground wire. I folded the cut end of the zip line back and taped it again so it would slip out from my wire. Then I wiped dish soap around the taped areas so it wouldn't stick inside the conduit. I fed the taped area into the conduit at the Tesla connector box and pulled the zip line down from the other end. I was pretty easy and I was able to do this without an assistant feeding the wire.

I terminated both ends tonight after work. I powered it up and saw 5 green lights which means working at 48 amps. Was able to connect to it with my cell and turn on WiFi. Then connected it to my AP and the Internet I assume to get updates.

Job done. I can cross it off my list.

I guess I am ready for my car!
 

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Yeah, I said "I thought" because I wasn't sure about that but was guessing. However, I did just go do some Googling for code sections, and I think I have found the section that specifies that. It's a section for designating ungrounded conductors in a branch circuit, which means hot wires.

It's 210.5(C)


(1) Branch Circuits Supplied From More Than One Nominal Voltage System
Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit shall be identified by phase or line and by system voltage class at all termination, connection, and splice points in compliance with 210.5(C)(1)(a) and (b). Different systems within the same premises that have the same system voltage class shall be permitted to use the same identification.
(a) Means of Identification. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means.

(b) Posting of Identification Means. The method utilized for conductors originating within each branch-circuit panelboard or similar branch-circuit distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment. The label shall be of sufficient durability to withstand the environment involved and shall not be handwritten.

----------------------------------

Specifically look there in (1) (a). It lists four possible ways of identifying, and the first one says "separate color coding". There is a list I have seen somewhere before of allowed colors for ungrounded conductors, which includes black, red, orange, blue, and some others, but I think this place saying "separate color coding" means that they do need to be two different color wires for the different wires in the circuit.

But that's if you are relying on just the wire insulation color. The next methods listed are "marking tape" and "tagging". So I think you could go ahead and use black insulated wire for both, but then you would need to pick one and mark it with red tape or something at every end or junction point to mark which one is being used as NOT black.

So I think that's my best guess. You can't leave them looking exactly alike, so either the colors need to be different or need to mark one to show it's different. The (b) section seems to be about how if you needed to use some system of marking or identifying that wasn't the obvious black/red, then you need to leave a printed legend explaining what the markings are.
This rule doesn't apply. Read the first clause: "Where the premises wiring system has branch circuits supplied from more than one nominal voltage system". How many voltage systems ya got in your home? :)

Anyway, from my memory of reading the code book, it only requires specific identification for grounding and grounded conductors (and prohibits those methods/colors from being used for other uses). Also for high-leg delta systems you have to identify the high leg differently (this ain't in your home). Beyond that, the only time phasing really matters is for motors. Some will argue that it's nice to know which wire is which for troubleshooting, which I can get behind, but that's not part of code.

You can 100% have both wires be black. I've done it in half the installations I've done, just because HD was out of red that day. Inspector passed 'em all.
 
I have also seen the use of black used for neutral with white tape at the ends in residential. Not sure if that is allowed by code but discovered it in the addition on a house I was refurbishing. I was replacing all outlets and switches after someone else had started the project and then quit. Many of the duplex outlets were split with one switched and the other not. They had a 30 year old remodeled edition and we had some dead circuits. Very confusing when I came across that black neutral with dirty white tape on it. I called in my electrician for some troubleshooting to help figure out where the wiring problem was.

I would have pulled a new white wire to replace that but it was not in conduit and not possible without opening up the wall. I call that horsesh1t wiring and don't approve but we re-wrapped the white tape to make it more obvious. Yuck!
 
This rule doesn't apply. Read the first clause: "Where the premises wiring system has branch circuits supplied from more than one nominal voltage system". How many voltage systems ya got in your home? :)
Yes it does apply. I have two and so do you. I found several pages that were discussing this, which were electricians talking about it for regular residential home wiring systems, which are split phase and have two "nominal voltage systems", 120V and 240V. Therefore the need to designate the different wires because you can have more than one hot phase that need to be identified in some way.

You can 100% have both wires be black.
...if you mark one of them with tape or some such, which is mentioned in that code section.
 
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Brought my new Model S home tonight. Only had a 35% charge when I arrived in Rockford. Plugged in my wall connector. It reported about 4 hours and 30 minutes at 48 amps required to charge up to 90%. I dropped the charge max level to 80% which might help the battery longevity. It has been charging so far for about 2 hours. The conduit is still cold. The flexible cable from the Wall Connector to the car is only slightly warm. I'm calling my Wall Connector install a success!