14/50 outlet for EV

N

nizak

Senior Member
Would it be a code violation to install 6/2 NM cable to feed a 14-50 EV Receptacle?

The charging device only requires H/H/G.

I don’t intend on wiring them this way just asking the question.

Thanks
 
Just make sure to cap off that unused neutral so it doesn't accidentally short against your hots.

Dumb me... phase tape to mark the conductor as hot. No different than an outdoor a/c condenser, stove, or clothes dryer.
 
zbang said:
OTOH, I think it would be a violation as that doesn't wire the device per the instructions, and while an EV might not need the neutral, that would be a problem if someone plugged an recreational vehicle into it.

(The instruction sheet for a Leviton receptacle clearly shows a neutral on the wiring diagram - https://leviton.com/content/dam/lev...instruction_sheet/Instruction-Sheet_1450R.pdf.)
Click to expand...
100% agree with zbang. The plug can forgo the neutral all day long but the receptacle must have the neutral.
 
I just installed one last week. I ran the neutral and connected it. I did this for two reasons.
1.) Instructions for the receptacle shows the neutral connection
2.) Customer may not keep the house and next owner may have an RV and plug into it
 
nizak said:
Would it be a code violation to install 6/2 NM cable to feed a 14-50 EV Receptacle?

The charging device only requires H/H/G.

I don’t intend on wiring them this way just asking the question.

Thanks
Click to expand...
It just depends on your minimum circuit ampacity. Some require 48 amps. EV charging circuits are continuous loads. If you use NM cable, you have to consider it as a 60 C. conductor. #6-2 NM has an ampacity of 55 amps. 48 x 125% = 60 It is my understanding that you need to size your branch circuit conductors and overcurrent devices for these circuits at 125% above the MCA.
 
Rick 0920 said:
It just depends on your minimum circuit ampacity. Some require 48 amps. EV charging circuits are continuous loads. If you use NM cable, you have to consider it as a 60 C. conductor. #6-2 NM has an ampacity of 55 amps. 48 x 125% = 60 It is my understanding that you need to size your branch circuit conductors and overcurrent devices for these circuits at 125% above the MCA.
Click to expand...
A 48A EVSE will not be cord & plug connected.
 
Rick 0920 said:
It just depends on your minimum circuit ampacity. Some require 48 amps. EV charging circuits are continuous loads. If you use NM cable, you have to consider it as a 60 C. conductor. #6-2 NM has an ampacity of 55 amps. 48 x 125% = 60 It is my understanding that you need to size your branch circuit conductors and overcurrent devices for these circuits at 125% above the MCA.
Click to expand...
The one I just wired had a setting on it and I wired it #8 THHN/THWN ran from the panel to the garage in EMT and set it for 50A breaker and the EVSE said the charge rate was 42A so the 125% was already baked into the EVSE
 
Willie Snyder said:
The one I just wired had a setting on it and I wired it #8 THHN/THWN ran from the panel to the garage in EMT and set it for 50A breaker and the EVSE said the charge rate was 42A so the 125% was already baked into the EVSE
Click to expand...
All the ones I've been involved with are like this. The 125% is already accounted for.

Rob G
Seattle
 
Willie Snyder said:
The one I just wired had a setting on it and I wired it #8 THHN/THWN ran from the panel to the garage in EMT and set it for 50A breaker and the EVSE said the charge rate was 42A so the 125% was already baked into the EVSE
Click to expand...
That would work fine as long as every termination in the circuit was rated for 75 C. heat. The OP stated he was using NM cable which has to be considered as a 60 C. conductor.
 
Rick 0920 said:
That would work fine as long as every termination in the circuit was rated for 75 C. heat. The OP stated he was using NM cable which has to be considered as a 60 C. conductor.
Click to expand...
#6 is good for 55A in the 60*C column I do agree it could be a violation to not install a grounded conductor on a receptacle but the conductor ampacity is sufficient with the information given.
 
marmathsen said:
All the ones I've been involved with are like this. The 125% is already accounted for.

Rob G
Seattle
Click to expand...
Granted they could go into the equipment and change the setting but that would be a code violation LOL
 
retirede said:
A 48A EVSE will not be cord & plug connected.
Click to expand...
For better or worse, they will be.

2026 NEC Sections 625.44(A), 625.44(B)
(A) Portable Equipment.
Portable equipment shall be connected to the premises wiring system by one or more of the following methods:
  1. A nonlocking, 2-pole, 3-wire grounding-type receptacle outlet rated at 125 volts or 250 volts, single phase in accordance with one of the following:
    1. 15 or 20 amperes
    2. 30 or 50 amperes listed and marked for EVSE and WPTE use
  2. A nonlocking, 3-pole, 4-wire grounding-type receptacle outlet rated at 125/250 volts, single phase in accordance with one of the following:
    1. 15 or 20 amperes
    2. 30, 50, or 60 amperes listed and marked for EVSE and WPTE use

Which means you have to run a neutral for your 60 amp EVSE, even though that neutral will not be useful.
And you're pretty much forced into the NEMA 14-60 connector despite the downsides of that connector.
But at least you can saw the neutral off and interchange with the NEMA 14-50.

The finger safe IEC 60309-2 connectors cannot be used (e.g. XLE-PA-IP67-309.NA-1PH-60A-250V-2P3W-C )
 
A long long time ago I did a Google search on the topic of wiring a typical residential 120/240 V panel for 120 V only, since I saw it at a customers house that day for the first time and it messed up a job I was about to install. I remember that this forum came up in the results with multiple threads discussing it and it seemed like everyone agreed that you can do it.

Why can you do that if it is specified as a 120/240 V panel? It definitely doesn’t say in any instruction or listing or labeling that you could do that. And if someone connected to that panel expecting 240 V, it could be disastrous for that equipment.

So my question is, why is that different than this topic of the 120/240 V 14-50 receptacle?
 
JohnHess said:
A long long time ago I did a Google search on the topic of wiring a typical residential 120/240 V panel for 120 V only, since I saw it at a customers house that day for the first time and it messed up a job I was about to install. I remember that this forum came up in the results with multiple threads discussing it and it seemed like everyone agreed that you can do it.

Why can you do that if it is specified as a 120/240 V panel? It definitely doesn’t say in any instruction or listing or labeling that you could do that. And if someone connected to that panel expecting 240 V, it could be disastrous for that equipment.

So my question is, why is that different than this topic of the 120/240 V 14-50 receptacle?
Click to expand...
Wiring up 240V equipment to a panel that was wired for only 120V won’t be disastrous. The voltage between the two busses will be zero. The equipment won’t function, but will not be damaged.
On the other hand, a 14-50 with no neutral will subject 120V loads with anywhere between 0 and 240V depending on what loads are present on each leg.
 
retirede said:
Wiring up 240V equipment to a panel that was wired for only 120V won’t be disastrous. The voltage between the two busses will be zero. The equipment won’t function, but will not be damaged.
On the other hand, a 14-50 with no neutral will subject 120V loads with anywhere between 0 and 240V depending on what loads are present on each leg.
Click to expand...
That depends on the equipment and what one considers disastrous, which is arbitrary. In a discussion of code I don’t think that comes into play. Further, multiple people have said that you have to use the neutral in the 14-50 receptacle because the instructions show it being used. The instructions for a 120/240 V residential panel shows two different legs being used, it definitely doesn’t show any type of connection between the two separate buses.
 
JohnHess said:
That depends on the equipment and what one considers disastrous, which is arbitrary. In a discussion of code I don’t think that comes into play. Further, multiple people have said that you have to use the neutral in the 14-50 receptacle because the instructions show it being used. The instructions for a 120/240 V residential panel shows two different legs being used, it definitely doesn’t show any type of connection between the two separate buses.
Click to expand...
How can you energize both buses in a 120V-only panel without the bus to bus voltage being zero?
 
retirede said:
How can you energize both buses in a 120V-only panel without the bus to bus voltage being zero?
Click to expand...
Again, different people have different definitions of what “disastrous“ is, and it’s all arbitrary. This is a discussion of code, conjecture on people’s opinions on what may or may not be disastrous results doesn’t come into play.
 
You must log in or register to reply here.
Top