My electrician used 6 gauge and was able to get it bent around conduit corners etc. It is thick and difficult to maneuver but manageable - and only has to be done once. 50 amp breaker with 6 gauge wire allows you to charge at 40 amp without fear of damage to wiring. I bought a ChargePoint Home Flex level 2 charger and love it. WiFi searches for lowest electricity rates and charges at night. By the morning, the car is up to the 80% charge limit that I set. Very happy.

 

Thanks, I'm using the OEM Chevy Dual charger. I just found out it runs on a 40 amp dedicated line.
So ..I think I'll use my 8/3 wire and a 40 amp breaker. 8 gauge is suitable for 40 amps and I have all the parts and I'm following GM's spec. Curious...what if I did use a 50 amp and 6/3 wire that wouldn't make any difference for charging rate or time just more protection on the circuit overheating...correct? Thanks

 

I think I'll use my 8/3 wire and a 40 amp breaker.

Don't do that! Breakers must be derated by 80% for continuous use, like an EV charger. You must use a 50 amp breaker if you want to draw 40 amps continuously.
And while I'm at it, don't use an el-cheapo big box store Leviton outlet. Get a robust Hubbell. More expensive, yes, but you don't want a fire as described in the video (post 5 above). I also recommend #6 wire.

 

@Vza Yes that is correct. However, #8/3 and 40A breaker is just fine for the OEM Chevy Dual charger.

 

If you use #8, then yes you need to limit yourself to a 40A breaker. However, #6 isn't all that much more and it future proofs the outlet. It's likely that the OEM EVSE will fail in a year or so. It's under warranty and GM will replace it, but after that happened to me, my OEM went in the trunk and an Autel 40A went on the wall.

Also, when you install it be sure to use an industrial receptacle made for continuous loads such as a Hubbell or a Bryant. There is a huge difference in the quality of those compared to a garden variety Leviton made for occasional use. Here's a good explanation from an engineer.

 

I really suggest you use 6 gauge wire with at least a 50 amp breaker. I have a 60 amp breaker I'm using with the GM provided EVSE. That is over kill now but who knows what's down the road. Not sure what your codes are, but I suggest you try not use a GFI breaker. There have been some bad reports linked to using a GFI breaker with the GM EVSE and the GFI breaker is more expensive.

 

I really suggest you use 6 gauge wire with at least a 50 amp breaker. I have a 60 amp breaker I'm using with the GM provided EVSE.

If you're using that with a 50 amp rated receptacle, that's an NEC violation. A 50 amp rated receptacle may only be on a circuit rated 50 amps or less.

Not sure what your codes are, but I suggest you try not use a GFI breaker.

Again, if the EVSE is connected via a receptacle, and you are under the 2020 NEC or later, then you need to use a GFCI breaker.

Cheers, Wayne

 

If you're using that with a 50 amp rated receptacle, that's an NEC violation. A 50 amp rated receptacle may only be on a circuit rated 50 amps or less.


Again, if the EVSE is connected via a receptacle, and you are under the 2020 NEC or later, then you need to use a GFCI breaker.

Cheers, Wayne

The GFCI's supposedly trip when trying to charge EV's, and thus the circuits.chargers are hard-wired to bypass that GFCI requirement. Cheers.

 

I'm not sure you really need to go the highest speeds. I have survived quite easily on three cars at 24 amp.

 

I also recommend running all 4 wires (L1, L2, N, G), even though an EVSE typically doesn't need a Neutral. An electrician might recommend not running the Neutral, to save a little money.

Running the Neutral can give greater flexibility in the future, should 120V be desired at that location. 120V requires Neutral.

 

Lots of different opinions. BTW in the video he downgrades from a 50 amp to 40 amp breaker to adhere to temp codes. I'm using the OEM Dual Charger which calls for 40 amp breaker drawing 32 to amps to charge which is 80% of what the 40 amp breaker covers. 40amp X 80% = 32 amp draw. So I may still put the 50A breaker w 6 gauge wire if Home depot takes back my 8 gauge wire. If not I'll go with the 40A w 8 gauge. As for the Bryant outlet they are 16.00 online, does that sound correct? Only 5.00 more than I paid for my Home Depot one. I'm assuming the 50A 6/3 only gives me more headroom as far as protection goes. Thanks V

 

You never mentioned if you are using #8 Romex, or #8 in a conduit. If Romex then technically limited to 40A breaker/32A EVSE. If in a conduit, 50/40A is OK.
The Bryant outlets typically run closer to $50. If you found a real one for $16 I'd buy a couple dozen and sell then on Ebay. ;-)

Bryant Electric 9450FR 50 Amp 125/250V NEMA 14-50R Flush Straight Blade Receptacle, Black - Electrical Outlets - Amazon.com

Bryant Electric 9450FR 50 Amp 125/250V NEMA 14-50R Flush Straight Blade Receptacle, Black - Electrical Outlets - Amazon.com

www.amazon.com

 

50 A isn't just more safety headroom. It allows faster charging with an appropriate EVSE. 2022-2023 Bolts AC charge at up to 48 A. With a 50 A circuit you can charge at 40 A (80%). With a 60 A circuit you can charge at 48 A, but that would need to be hard wired.

 

Romex either #8 or #6 depending on whats available to me by the foot.
Leaning to 40A w/ #8/3 as LoneR stated is good w/ OEM GM dual charger.
I found this https://www.amazon.com/Bryant-Elect...BhBtEiwAq5aX2BiFwR9w2c0bjl6ImlHxJqfgmzcnU3pcHsHuTlp53UcSv3CCo696rhoCLRMQAvD_BwE

 

I found this https://www.amazon.com/Bryant-Elect...BhBtEiwAq5aX2BiFwR9w2c0bjl6ImlHxJqfgmzcnU3pcHsHuTlp53UcSv3CCo696rhoCLRMQAvD_BwE

That's the one I purchased to replace my HD Leviton. It's definitely a Bryant, with the clamps to secure the wires. I think the metals used may not be the same as the $50+ Bryant/Hubell units, and it may not be quite as deep as the more robust versions, but it's running cool. I'm happy with it.

 

Check Grainger for Bryant. $32?

 

As for the Bryant outlet they are 16.00 online, does that sound correct? Only 5.00 more than I paid for my Home Depot one.

That's the one I purchased to replace my HD Leviton. It's definitely a Bryant, with the clamps to secure the wires. I think the metals used may not be the same as the $50+ Bryant/Hubell units, and it may not be quite as deep as the more robust versions, but it's running cool. I'm happy with it.

That is the cheap residential version. Note the Phillips head screws and wire mangling terminals. It's also much less massive.

It's nothing like the recommended one.

You want the 9450FR: https://www.amazon.com/gp/product/B07R4LVX18/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

The quality of the 240v outlet is not an issue since I live in Los Angeles and the local code requires a hard-wire installation. Fine with me - I would not be plugging and unplugging the charger's power cord anyway and I saved money not having to buy a receptacle. Win, win!

 

Hard wiring is generally the way to go whenever possible.

 

Vince
Pretty sure you need 6ga wire for a 50a breaker

Dave

 

Vince
Pretty sure you need 6ga wire for a 50a breaker

Dave

True for Romex/NM-B... for THHN in a conduit you can use the 90C ampacity and 8 gauge will suffice for a 50 amp circuit (40 amp continuous).

The annoying thing is we all know it's the same wire as THHN inside that Romex rubberized jacket.

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

 

I used 6 gauge.

 

Trust the 6-gauve. It can carry more amps a longer distance with no power loss. Have a sub panel installed in the garage and you can get your money's worth from a few more circuits. And look out for anyone who say they save money. Especially for the ground wire. My charger loves running at 9.8 kw

 

The vast majority of EVSEs don't need the Neutral wire. They do need a Ground, though.

Regardless, run all four wires.

 

You need 6 gauge at a minimum, 6/3 Romex plus ground, and a 40 amp breaker for a max of 32 amp continuous load. Eight gauge Romex is good for 24 amp continuous, which will give you 18 mi/hr charge rate, vs 25 mi/hr for the 6 gauge. Good luck.

 

Not correct. 8 gauge romex is good for 40 amps, 32 continuous, while 6 gauge is is good for 55 amp or 44 amp continuous.

 

I wound up using 6/3 with the heavy duty Bryant and 50A breaker. BUT I'm confused ...the gauge wire and amperage of the breaker dosen't determine the charge amount? The OEM dual charger uses 32A with the 240V outlet ....its not going to go beyond that correct? That's if I use a different rated charger that charges at a higher rate. V

 

Correct. The OEM charger will draw 32 amps max. Your circuit is capable of supporting 40 amps if you buy an aftermarket charger. You're car (Bolt) is capable of handling 32 amps max (2017-21) or 48 amps max (22-23).

 

Cool Thanks V

 

When close I say go big.

 

I have to assume that everybody here talking about wire ampacity is using THHN or Romex Copper wire and not aluminum. That change requires a step up in wire size for most amperage ratings.

 

I bought a 2022 bolt in Dec 13 2023. I live in double wide with telephone pole near home I have 100 amp box on pole and ran 8 gauge wire to 240 receptacle mounted on pole beside box weather proof plug I have 60 amp breakers and run grizzl-e type 2 charger. This works great I have no problem charging. Cold weather below 32 runs 170 t0 175 charge and if warmer runs 185 to 208 charge hot weather runs 230 to 240. I charge at 100 percent

 

Careful!

Those double-wides are well-known tornado-attractors, and more recently, crashing-plane attractors.

 

You're running a 60 amp breaker to a 50 amp receptacle (presumably NEMA 14-50r)? Also, you have 100 amp service and 60 amps going to your EV charger? Have you ever tripped the main breaker?

My question would be are you melting the 8 gauge wire?

No melting charger is on breaker and wire by itself runs straight off meter to box
No tripping

 

But... why? Why put a 50 amp receptacle on a 60 amp breaker with wire that is appropriate fro a 40 amp circuit?

 

But... why? Why put a 50 amp receptacle on a 60 amp breaker with wire that is appropriate fro a 40 amp circuit?

No breaker tripping

60 amp breakers are too large for 8 gauge wire. You are not wired per code and if you loaded the circuit to the max you risk a fire.

It is only plug on circuit

60 amp breakers are too large for 8 gauge wire. You are not wired per code and if you loaded the circuit to the max you risk a fire.

It is only plug on circuit

 

No breaker tripping

It is only plug on circuit

It is only plug on circuit

Dedicate line