60A Breaker -> 4 gage or 6 gage wire?

[rdlink]

Hope you meant "hot and hot". ;-) The HPWC does not use the Neutral.

Glad you got it worked out! I did 6 AWG and that was difficult enough.

Thanks! Yeah. Should have said that.

I learned a some key things while doing this that might be beneficial to others, and will definitely be beneficial to me, as I have to wire up another, almost identical setup at my stepdaughter's house for her boyfriend's new Model 3:

• The terminals are plenty large enough to accommodate 4 awg wire. I was really concerned that it would be tight after looking at only pictures. As GWord said earlier, these terminals look like they'll accommodate even 2 awg wire (I pity the person doing that work...).
• I have discovered that it seems really difficult to keep the terminals in the "open" position when the charger is mounted on the wall. Gravity is not your friend. I found the terminals stay open for insertion much better if the charger is upside down. Not sure how this would work for some installations, but when I install the one for my stepdaughter's boyfriend I am going to terminate the wires in the charger before I even run the wire into the wall and terminate to the breaker panel. This will work for me because the wire will only need to be about 3 feet. But you should consider terminating the wires prior to mounting the charger, if practical for your installation.
• There are two rear entry holes in the charger base for routing wires. The low profile bracket has a cutout for the top, smaller one, and it seems logical to use it, since it's closer to the terminals. However, I would recommend using the lower, larger hole. This will give you more room to maneuver the wires inside the charger.
• If you have some spare 4 awg wire (only about 6-8 inches necessary) I would consider cutting a short piece, and using a single lead as a "test" piece for the bend. Bend and shape it until you have a piece that fits into the terminal nicely coming in from the rear. Then use that as a template to pre-bend the actual wires that you will be terminating, prior to routing them into the charger. This should make it much easier, since it is difficult to maneuver heavy enough pliers to bend the wires inside of the charger.

I hope this helps anyone who is planning to wire their own charger.

 

[SDRick]

rdlink, great tips, wish I would've had them two years ago!

 

[smsiegel33]

Could be a dumb question but i figure i'll ask it anyway. My electrical panel and garage are on opposite sides of the house so this wire thing is quite an expensive difference for me (looking at around 100' or so). I would like to go 4/3 but already found a great deal on some 6/3 ($1.4/ft) that i pulled the trigger on. Now the best i can find for 4/3 is $4.1/ft which significantly increases the cost. Can someone with more electrical knowledge give me a yah or nah for the following situations:

1. 60 amp breaker, 6/3 wire, NEMA 15-40 outlet (mobile connector limited to 32A). This is the most likely scenario given the costs and needs. A nights sleep should be sufficient to charge 99% of our daily uses.
2. 60 amp breaker, 6/3 wire, HPWC plugged into NEMA15-40 outlet (i assume the HPWC knows it is a 15-40 and limits the amps to 40A)
3. 60 amp breaker, 6/3 wire, hardwired HPWC (capable of 48A) but i reduce the maximum amps in the car to 44A or whatever is allowable for 6/3). I think i have seen in videos that you can reduce the charging amperage on the screen but maybe i am wrong. Cant you also set a dail in the HPWC to reduce the output? I would imagine that since the HPWC is capable of an amperage over the rating that this option would not be allowed.

 

[1.21GW]

1. a NEMA 14-50 outlet can only have a 50 amp breaker MAX
2. I don't think that meets code, I'm not an expert so consult an electrician first.
3. You can set the HPWC at a lower amperage that would work with 6/3

 

[Rocky_H]

Could be a dumb question but i figure i'll ask it anyway. My electrical panel and garage are on opposite sides of the house so this wire thing is quite an expensive difference for me (looking at around 100' or so). I would like to go 4/3 but already found a great deal on some 6/3 ($1.4/ft) that i pulled the trigger on. Now the best i can find for 4/3 is $4.1/ft which significantly increases the cost. Can someone with more electrical knowledge give me a yah or nah for the following situations:

1. 60 amp breaker, 6/3 wire, NEMA 15-40 outlet (mobile connector limited to 32A). This is the most likely scenario given the costs and needs. A nights sleep should be sufficient to charge 99% of our daily uses.
2. 60 amp breaker, 6/3 wire, HPWC plugged into NEMA15-40 outlet (i assume the HPWC knows it is a 15-40 and limits the amps to 40A)
3. 60 amp breaker, 6/3 wire, hardwired HPWC (capable of 48A) but i reduce the maximum amps in the car to 44A or whatever is allowable for 6/3). I think i have seen in videos that you can reduce the charging amperage on the screen but maybe i am wrong. Cant you also set a dail in the HPWC to reduce the output? I would imagine that since the HPWC is capable of an amperage over the rating that this option would not be allowed.

First off, let's establish what you actually have. Since you say 6/3, is that bundled cable in a black rubber sheath? That's I think officially called NM-B cable. According to the ampacity tables that show how many amps are allowed for each gauge and type of wire, it says 6 gauge of that type is only rated up to 55A. So all three of your suggestions of using 60A circuits cannot be done.
Ampacity Charts

Now more specifically, as @1.21GW pointed out, you can't put a 14-50 outlet on a 60A breaker anyway, so that's not happening. The 6/3 cable (at a great price) can go as a 50A circuit. You can put a 14-50 outlet on it, but the mobile charge cable does limit it to 32A. I would probably suggest to install the wall connector hard wired (since that is how it is intended to be installed) on the end of that circuit.

Yes, the wall connector does have a switch inside it where you set what level of circuit it's on. So you would set it for a 50A circuit, providing 40A output.

 

[smsiegel33]

Yes i have the black wrapped southwire romex cable i got from Lowe’s. If you are interested in 6/3, shop at the Hibbings, MN store and have it shipped to your house.

Thanks for all of the input. I think I rushed in some of the typing. Obviously 50 amp outlet should have a 50 amp breaker.

The decision I guess I need to make is to either be ok with 32 amps, put money into wire, or put money into a HPWC, or both. I guess I am more inclinded to do wire and hope I can refer someone and get the free HPWC down the road. From what I hear, routing that 4 gauge wire ~100 feet, up through a wall, and into the charger would be a beast. Electrician I know said they would come bless everything, or tell me things i needed to do differently. He’s not exactly excited about routing all that wire and his price shows it.

 

[Skione65]

I think what size charging ability you deploy all comes down to each individuals situation and goals. I would say there is no right or wrong solution here.

I will call out a couple data points:

• After only owning a Model 3 for a few weeks I have had a couple of occasions where I came home after work and wanted to top off before going on a long trip. So I was glad to have the full 48a charge capability (I still did not get it as full as I would have liked - charged to 90% the night before, then got home after commute at 80% and wanted to take it to 100%, but only got it back to 90%)
• My commute is very reasonable (about 30 miles round trip) and I have been able to bring myself back up to an 80% state of charge (which I charge to every night) with an hour or a little more of charging each evening. This is clearly overkill, but it is nice to know I am back to 80% quickly in case I need to make an unexpected trip somewhere, the power goes out, or we have a natural disaster.

My personal feelings are that the capital costs for a large charger are a drop in the bucket compared to the cost of the car, and much of the installation (the conduit and wire) likely has an extremely long useful life (beyond that perhaps of this electric car) so it is kind of a no brainer. But to each their own, there is no right answer here.

@eprosenx,

Agree totally. I’m putting in a Tesla Wall Charger for my 3. I want to future proof for possibility of another 3 or maybe an S. Therefore I’m putting in dual pole 100A breaker at the main...in the basement and about 50’ either 2 AWG or 3 AWG (prob 2) through the garage and over 2 garage doors (opposite side of garage) in 1” EMT.
My main question is due to code I’m putting in a GE 100A disconnect switch above my Wall Charger due to Main Panel being in the basement. I’m not sure if I want a “fused” or “non-fused” disconnect. At first I wanted fused (100A) because a felt it would add an “extra layer of protection” between the Main Panel and Wall Charger for circuit faults and/or overload. However, I read (attached above) on TMC, which is a valid argument....but if you have spare fuses on hand it’s not.
So in your opinion would you recommend a fused or non-fused disconnect? I realize a non -fused would be better for simplicity but a fused I feel would add another layer of protection but is that warranted or not necessary?

Any advice would be appreciated.

Ski

 

[mongo]

View attachment 324473

@eprosenx,

Agree totally. I’m putting in a Tesla Wall Charger for my 3. I want to future proof for possibility of another 3 or maybe an S. Therefore I’m putting in dual pole 100A breaker at the main...in the basement and about 50’ either 2 AWG or 3 AWG (prob 2) through the garage and over 2 garage doors (opposite side of garage) in 1” EMT.
My main question is due to code I’m putting in a GE 100A disconnect switch above my Wall Charger due to Main Panel being in the basement. I’m not sure if I want a “fused” or “non-fused” disconnect. At first I wanted fused (100A) because a felt it would add an “extra layer of protection” between the Main Panel and Wall Charger for circuit faults and/or overload. However, I read (attached above) on TMC, which is a valid argument....but if you have spare fuses on hand it’s not.
So in your opinion would you recommend a fused or non-fused disconnect? I realize a non -fused would be better for simplicity but a fused I feel would add another layer of protection but is that warranted or not necessary?

Any advice would be appreciated.

Ski

I'd say unfused, less contact surfaces.
Double check code on the disconnect, I had thought they were needed, but my most recent reading makes it appear that, as long as you can lock out the breaker (and the lock out device is permanently attached) , you do not need a local disconnect. NEC 625.23 for EVSE.

 

[tga]

@Skione65 -

@Solarguy has a great post here - Post Pictures of HPWC Installations (Residential and Commercial) (actually, that whole thread is great).

Another advantage to a disconnect (or garage subpanel) is that most are AL rated. You can run 1ga or 1/0 AL to the panel/disconnect, then only a few feet of 2ga Cu to the HPWC.

A long run of 2 or 3 ga copper is insanely expensive. Larger AL is a fraction of the cost, but you can't run AL straight to the HPWC; it's terminals aren't AL rated.

 

[mongo]

@Skione65 -

@Solarguy has a great post here - Post Pictures of HPWC Installations (Residential and Commercial) (actually, that whole thread is great).

Another advantage to a disconnect (or garage subpanel) is that most are AL rated. You can run 1ga or 1/0 AL to the panel/disconnect, then only a few feet of 2ga Cu to the HPWC.

A long run of 2 or 3 ga copper is insanely expensive. Larger AL is a fraction of the cost, but you can't run AL straight to the HPWC; it's terminals aren't AL rated.

Or you can add a junction box for the splice.

 

[tga]

Or you can add a junction box for the splice.

True - you can get "pre-gooped" Polaris-style connectors that are rated for splicing Al to Cu. The electrician used them to extended the 6 ga Al SEU feeding my range 10-50 when upgrading my main panel.

 

[mongo]

True - you can get "pre-gooped" Polaris-style connectors that are rated for splicing Al to Cu. The electrician used them to extended the 6 ga Al SEU feeding my range 10-50 when upgrading my main panel.

Those are some nice looking connectors.

 

[tga]

Those are some nice looking connectors.

The specific ones he used were Brundy Bit4 14-4 AWG - http://ecat.burndy.com/Comergent/en...geType=catProductDetailMob&showAddButton=true

 

[Skione65]

I'd say unfused, less contact surfaces.
Double check code on the disconnect, I had thought they were needed, but my most recent reading makes it appear that, as long as you can lock out the breaker (and the lock out device is permanently attached) , you do not need a local disconnect. NEC 625.23 for EVSE.

@mongo,

Even though the Main Panel is not “Line of sight” in the garage and is in the basement? I have seen photos of a lockout put on breakers in panels. Those disconnects are sure ugly and it’d be a much cleaner/sleeker install without for sure.

Ski

 

[Skione65]

@Skione65 -

@Solarguy has a great post here - Post Pictures of HPWC Installations (Residential and Commercial) (actually, that whole thread is great).

Another advantage to a disconnect (or garage subpanel) is that most are AL rated. You can run 1ga or 1/0 AL to the panel/disconnect, then only a few feet of 2ga Cu to the HPWC.

A long run of 2 or 3 ga copper is insanely expensive. Larger AL is a fraction of the cost, but you can't run AL straight to the HPWC; it's terminals aren't AL rated.

@tga,

Thanks. I’d rather keep it all Cu. I can do the run for around $180 for just the #2 Cu. Not too bad. After the cost of a P3D+ it’s a pittance.

I’ll check out his thread. I’ve read some really good ones the past few days.

Ski

 

[okii]

I have received a few quotes to install my Tesla Wall Connector for my model 3. The biggest difference between the quotes is wire size. All electricians have their reasons, i’d like to know what you think

My setup:
60A circuit breaker
48A max charging amps (wall connector setting #9)
35 ft. From breaker box to connector location

Wire Ampacity Ratings
6/3 Romex = 55A
4/3 Romex = 70A

Contractor #1
6/3 Romex
NEC 240.4(B) exception allows rounding to next highest breaker size if wire ampacity is in between breaker sizes.

Contractor #2
4/3 Romex
+$220 more expensive

As a side note, what wire size are you running to your Tesla Wall Connector (HPWC)? Also I am doing the 3 wire so I can replace my HPWC with a NEMA 14-50 when I move.

Hello

 

[okii]

Hello-

I'm new to all this, but my Model 3 long range is being delivered in 2 days. When I bought they said 4-6 weeks. That was a 2 weeks ago.
I have a 200 amp panel in my garage and I have two options for the $500 wall charger (HPWC?).

I could place a 14-50 NEMA outlet directly below the main breaker panel with 6/3 NM-B romex wire (about 2 feet) and install a 50 amp breaker. Very simple to do....No drilling studs, etc.. I would mount the HWPC a short distance (3 feet) to the side of the main breaker panel. I would wire a 50 amp rated appliance cord with a NEMA plug to the HWPC and the use that to connect to the NEMA outlet. I realize that only gets me 40 amp max charging capacity. However, I could easily take charger if I move, or replace if faulty.

Second option is to drill through stud next to panel and run 4/3 copper wire to where the HPWC is to be mounted. I would connect the wires directly to the HWPC and use a 60 amp breaker. This will provide me 48 amp max charging.

Couple questions I have:

The Ampcity chart lists different amperage for the same gauge wire depending on temperature. What temperature are they referring to? Ambient room temp? What is the correct temp to be using to determine the wire gauge/amperage capacity?

I can find 6/3 Romex at my local HomeDepot. I don't think they carry 4/3 romex. Is that even available? Do I need 4 gauge NM-B wire for a 60 amp circuit???

The Ampcity chart says you can use 6 gauge THW or THWN type wire (at 75 degrees) for 65 amps. I believe that type of wire comes as individual wires, not bundled like Romex. If so, would I need to place those in a conduit within the wall. Does the conduit need to be emt? Can I use plastic conduit?

Thanks,

Okii

 

[P85_DA]

If so, would I need to place those in a conduit within the wall

Yes THHN must be run in conduit

 

[GWord]

Hello-

I'm new to all this, but my Model 3 long range is being delivered in 2 days. When I bought they said 4-6 weeks. That was a 2 weeks ago.
I have a 200 amp panel in my garage and I have two options for the $500 wall charger (HPWC?).

I could place a 14-50 NEMA outlet directly below the main breaker panel with 6/3 NM-B romex wire (about 2 feet) and install a 50 amp breaker. Very simple to do....No drilling studs, etc.. I would mount the HWPC a short distance (3 feet) to the side of the main breaker panel. I would wire a 50 amp rated appliance cord with a NEMA plug to the HWPC and the use that to connect to the NEMA outlet. I realize that only gets me 40 amp max charging capacity. However, I could easily take charger if I move, or replace if faulty.

Second option is to drill through stud next to panel and run 4/3 copper wire to where the HPWC is to be mounted. I would connect the wires directly to the HWPC and use a 60 amp breaker. This will provide me 48 amp max charging.

Couple questions I have:

The Ampcity chart lists different amperage for the same gauge wire depending on temperature. What temperature are they referring to? Ambient room temp? What is the correct temp to be using to determine the wire gauge/amperage capacity?

I can find 6/3 Romex at my local HomeDepot. I don't think they carry 4/3 romex. Is that even available? Do I need 4 gauge NM-B wire for a 60 amp circuit???

The Ampcity chart says you can use 6 gauge THW or THWN type wire (at 75 degrees) for 65 amps. I believe that type of wire comes as individual wires, not bundled like Romex. If so, would I need to place those in a conduit within the wall. Does the conduit need to be emt? Can I use plastic conduit?

Thanks,

Okii

The temp rating refers to the insulation rating on the wire. Romex style cable is rated from the 60C table. If you want the full 48A from an HPWC you will need something other than Romex 6/3.

 

[eprosenx]

Hello-

I'm new to all this, but my Model 3 long range is being delivered in 2 days. When I bought they said 4-6 weeks. That was a 2 weeks ago.
I have a 200 amp panel in my garage and I have two options for the $500 wall charger (HPWC?).

I could place a 14-50 NEMA outlet directly below the main breaker panel with 6/3 NM-B romex wire (about 2 feet) and install a 50 amp breaker. Very simple to do....No drilling studs, etc.. I would mount the HWPC a short distance (3 feet) to the side of the main breaker panel. I would wire a 50 amp rated appliance cord with a NEMA plug to the HWPC and the use that to connect to the NEMA outlet. I realize that only gets me 40 amp max charging capacity. However, I could easily take charger if I move, or replace if faulty.

Second option is to drill through stud next to panel and run 4/3 copper wire to where the HPWC is to be mounted. I would connect the wires directly to the HWPC and use a 60 amp breaker. This will provide me 48 amp max charging.

Couple questions I have:

The Ampcity chart lists different amperage for the same gauge wire depending on temperature. What temperature are they referring to? Ambient room temp? What is the correct temp to be using to determine the wire gauge/amperage capacity?

I can find 6/3 Romex at my local HomeDepot. I don't think they carry 4/3 romex. Is that even available? Do I need 4 gauge NM-B wire for a 60 amp circuit???

The Ampcity chart says you can use 6 gauge THW or THWN type wire (at 75 degrees) for 65 amps. I believe that type of wire comes as individual wires, not bundled like Romex. If so, would I need to place those in a conduit within the wall. Does the conduit need to be emt? Can I use plastic conduit?

Thanks,

Okii

I do *not* recommend doing a pigtail from a Wall Connector. In addition to limiting you to 50a (40a usable) and being against the install instructions / code, it also bypasses a key safety feature (the temp sensor in the plug end). I recently helped someone else on the forum that did this and they nearly had a fire since the receptacle was wired wrong (insulation pinched in the terminal). Luckily he was monitoring his new install closely and detected excessive heat.

Note that even if you hard wire you can absolutely still take it with you when you leave... Just cap the wires and wall plate over them (or replace with a 14-50 or 6-50 receptacle with a 50a breaker).

You are right about needing 6 AWG wire for a 50a circuit if it is NM cable (Romex). 4 AWG would be required if you wanted to support a 60a breaker and still use Romex. Note that the Wall Connector has zero use for a neutral wire and it would just be in the way. They do make 4awg romex. 4-3 W/G NM-B Wire Black

I installed my Wall Connector with conduit which allows you to use the 75c insulation rating which gives you the ability to do 60a on 6 AWG (that is what I did). Though now that I think about it only has 5 amps of headroom to use on a 60a circuit (48a continuous draw by Model 3). So technically my install is only good to about 100 degrees Fahrenheit ambient temp.

THHN is what you want for use in conduit (usually dual rated as THWN or THWN-2).

The conduit could be EMT or plastic. Many people find the plastic easier to work with, but I vastly prefer EMT. I used EMT.

You could just use "flex" as well. Just make sure to use the proper fittings on the end with bushings to make sure the sharp Flex ends don't cut the wire.