Things to consider when DIY installing a wall charger / outlet

ClaudeMach-E

Well-Known Member
First Name
Claude
Joined
Mar 28, 2020
Threads
9
Messages
1,076
Reaction score
828
Location
Quebec Canada
Vehicles
Mustang Mach 3- Tempo- Malibu(3)-Actual Kia Sportage AWD
Occupation
Retired
Country flag
The problem I have with some of those multimeters is the probes aren't long enough
On mine the protective cover on the tips are removable so once you remove them the actual probe is longuer.
Sponsored

 

CHeil402

Well-Known Member
First Name
Chris
Joined
Sep 21, 2020
Threads
8
Messages
723
Reaction score
1,314
Location
King of Prussia, PA
Vehicles
2017 Audi A4, 2021 MME
Occupation
Electrical Engineer
Country flag
I am a Licensed Electrician retired. I do not agree with you. Neither you or I can
always be right. So when you draw your electric prints do you state :
"I want two 120 volts lines at this location"
"I want one 240 volt line at this location"
Which statement is correct ?
I have made the call to Inspect. Dept. I am done trying to explain as I have
contacted the proper people. My 50 amp 6 awg 240 volt charger circuit
will have a disconnect.
First of all, it would depend on the system. That's why I keep specifying residential service which is typically split-phase, so 120 V to ground. If we're talking about commercial, then it would typically be three phase 208 V to ground. In your example, I would specify I want a "NEMA 14-50 outlet". That would clearly define that I want a +120 V, -120 V, neutral, and ground connection.

If this were 208 V to ground (commercial) then it would be required. Also, there is nothing that prohibits a disconnect, so there is no harm in adding one if you want, it's just not required.

Also, if you read the Tesla wall charger install manual: "NOTE: External disconnect switches are neither required nor recommended.". And they have lots of engineers and lawyers who wouldn't publish that if it weren't true.
 

RonTCat

Well-Known Member
First Name
Ron
Joined
Jul 21, 2020
Threads
27
Messages
1,110
Reaction score
2,927
Location
USA
Vehicles
Mach-E wannabuy
Country flag
First of all, it would depend on the system. That's why I keep specifying residential service which is typically split-phase, so 120 V to ground. If we're talking about commercial, then it would typically be three phase 208 V to ground. In your example, I would specify I want a "NEMA 14-50 outlet". That would clearly define that I want a +120 V, -120 V, neutral, and ground connection.

If this were 208 V to ground (commercial) then it would be required. Also, there is nothing that prohibits a disconnect, so there is no harm in adding one if you want, it's just not required.

Also, if you read the Tesla wall charger install manual: "NOTE: External disconnect switches are neither required nor recommended.". And they have lots of engineers and lawyers who wouldn't publish that if it weren't true.
Yes, if I had a 3-phase feed I would install a service disconnect per code. But residences rarely, almost never, have 3-phase power feeds.
 

timbop

Well-Known Member
First Name
Tim
Joined
Jan 3, 2020
Threads
63
Messages
6,729
Reaction score
13,758
Location
New Jersey
Vehicles
Solar powered 2021 MME ER RWD & 2022 Corsair PHEV
Occupation
Software Engineer
Country flag
It's pretty clear:



It states 150V *to ground*. Each leg of a residential 240V outlet is 120V to ground. They are only 240V relative to each other.

Level 2 chargers are fine without it. Would be happy to hear from an electrician.
The reason is for safety with someone turning it on because the device (when being worked on) is not visible from the breaker. This is how my electrical inspector explained it to me when he required me to get a lockout to go on my water heater breaker (single phase 240). If the panel and outlet are in the garage, you don't need one. Conversely, it is standard practice to have a disconnect outside by an air conditioner compressor.

The inspector said I should have put in a disconnect by the water heater, but said I could put the lockout on the breaker so he wouldn't have to come back to reinspect the connections. The lockout is just a guard that goes on top of the breaker, so no rewiring
 

sockmeister

Well-Known Member
Joined
Sep 24, 2020
Threads
6
Messages
1,879
Reaction score
2,992
Location
Pennsylvania
Vehicles
2021 Mustang Mach-E4x
Occupation
SW Engineer
Country flag
The reason is for safety with someone turning it on because the device (when being worked on) is not visible from the breaker. This is how my electrical inspector explained it to me when he required me to get a lockout to go on my water heater breaker (single phase 240). If the panel and outlet are in the garage, you don't need one. Conversely, it is standard practice to have a disconnect outside by an air conditioner compressor.
Makes logical sense. Mine are both in the garage within a foot of each other.
 


All Hat No Cattle

Well-Known Member
Joined
Oct 24, 2020
Threads
19
Messages
446
Reaction score
564
Location
Las Vegas
Vehicles
2023 Genesis GV-80 , 2017 Edge Titanium
Country flag
This disconnect will not meet NEC code. In the new code ALL conductors must
be disconnected. The 2 Hots and 1 neutral. This will need a 3 Phase Non fused
disconnect.
Sweetwater, were you by any chance a commercial electrician?

Do 230 volt, single phase, EV chargers require 2 hot wires, plus a neutral wire, plus a ground wire?

If so, then I stand corrected. If not, then there is nothing wrong with the disconnect from Home Depot.
 

timbop

Well-Known Member
First Name
Tim
Joined
Jan 3, 2020
Threads
63
Messages
6,729
Reaction score
13,758
Location
New Jersey
Vehicles
Solar powered 2021 MME ER RWD & 2022 Corsair PHEV
Occupation
Software Engineer
Country flag
Sweetwater, were you by any chance a commercial electrician?

Do 230 volt, single phase, EV chargers require 2 hot wires, plus a neutral wire, plus a ground wire?

If so, then I stand corrected. If not, then there is nothing wrong with the disconnect from Home Depot.
single phase does not include the neutral, just 2 hots and a ground so no need for the neutral on a hardwired EVSE. Some would argue that putting in a nema 14-50 you SHOULD still have the neutral, but for every EVSE I've seen there is no connection to the neutral pin.

And for information, the ground and neutral are electrically the same; they are both connected to the same bus in the service panel.
 
Last edited:

timbop

Well-Known Member
First Name
Tim
Joined
Jan 3, 2020
Threads
63
Messages
6,729
Reaction score
13,758
Location
New Jersey
Vehicles
Solar powered 2021 MME ER RWD & 2022 Corsair PHEV
Occupation
Software Engineer
Country flag
or look at your own diagram; the green ground is tied to the neutral:
Ford Mustang Mach-E Things to consider when DIY installing a wall charger / outlet Screen Shot 2020-12-05 at 10.04.16 PM
 

janitorjim

Well-Known Member
Joined
Jul 19, 2020
Threads
27
Messages
658
Reaction score
1,603
Location
plano
Vehicles
ford f150 2001, explorer xlt 2013
Country flag
no need for the neutral on a hardwired EVSE. Some would argue that putting in a nema 14-50 you SHOULD still have the neutral, but for every EVSE I've seen there is no connection to the neutral pin.

...the ground and neutral are electrically the same...

or look at your own diagram; the green ground is tied to the neutral:
Screen Shot 2020-12-05 at 10.04.16 PM.png
this is why I wrote NOT exactly. They are connected there but NOT the same. Watch the video for more in depth info

plus the plugs do have a neutal "pin" for the exact reason stated in the video, if you do watch it, the "pin" is not for show.

Ford Mustang Mach-E Things to consider when DIY installing a wall charger / outlet unnamed


here is another video that specifically talks about the ground and neutral usage (go to 5:43)

 
Last edited:

CHeil402

Well-Known Member
First Name
Chris
Joined
Sep 21, 2020
Threads
8
Messages
723
Reaction score
1,314
Location
King of Prussia, PA
Vehicles
2017 Audi A4, 2021 MME
Occupation
Electrical Engineer
Country flag
single phase does not include the neutral, just 2 hots and a ground so no need for the neutral on a hardwired EVSE. Some would argue that putting in a nema 14-50 you SHOULD still have the neutral, but for every EVSE I've seen there is no connection to the neutral pin.

And for information, the ground and neutral are electrically the same; they are both connected to the same bus in the service panel.
If you're hardwiring an EVSE then you would need to connect it according to the installation manual of the EVSE. If it needs 120 V for internal operation (for smart functions) then you need the neutral. But as you point out, many don't need it. However, a NEMA 14-50 outlet MUST have the neutral. Any appliance that uses a NEMA 14-50 outlet may be counting on the neutral and might need it. Otherwise, there are 240 V outlets that specifically don't include the neutral.

However, ground and neutral are not at all the same thing. While they may be at the same electrical potential they are not the same. Otherwise, again, why would there be NEMA outlets with and without neutral?

or look at your own diagram; the green ground is tied to the neutral:
Screen Shot 2020-12-05 at 10.04.16 PM.png
@janitorjim is absolutely correct. While neutral and ground are tied together, this is for bonding purposes. Your ground and neutral need to be at the same potential but for safety grounding. Technically, grounding is never needed for anything other than safety. The reason you tie them at one point, and only one point, is so there is no complete circuit to ground unless there is a fault. If you start connecting them at multiple places, you'll create ground loops which are bad.
 

Accord07

Well-Known Member
Joined
Dec 5, 2020
Threads
4
Messages
543
Reaction score
707
Location
Pennsylvania
Vehicles
Star White Mach-E Premium AWD ER
Country flag
For what it is worth, the two EVSE I have looked at - Ford Connected Charge Station and ChargePoint Home Flex - have only three terminals on their input side, two hot wires and one ground. However, if there is any chance that the EVSE might be removed later and the wiring is re-used for a NEMA 14-xx receptacle, then you might as well run the fourth wire (neutral) now as Ford's installation guide suggests.
 

shutterbug

Well-Known Member
First Name
Joseph
Joined
Nov 5, 2020
Threads
8
Messages
1,113
Reaction score
1,549
Location
AZ
Vehicles
Grabber Blue FE
Country flag
Not sure that I should take advice from a guy who writes this:

Coal-powered cars, commonly called "EV" or electric vehicles, are the dirtiest, most energy-consuming form of personal transportation in existence today. The common wisdom, or lack thereof, is that somehow electric power is free and is generated without any pollution whatsoever, if it's stored in toxic batteries (the lithium for which is energy-intensive to obtain) and then used to power a vehicle. Due to this utter nonsense, politicians are touting electric vehicles as some sort of solution to a host of problems they merely exacerbate.
So instead of using electric vehicles only in the limited applications for which they make sense, schemes are now underway to use them in place of internal combustion engine cars. This means more electrical vehicle charging system work for electricians. It also means faster depletion of worldwide oil reserves and more pollution...
 

macchiaz-o

Well-Known Member
First Name
Jonathan
Joined
Nov 25, 2019
Threads
168
Messages
8,157
Reaction score
15,299
Location
🔑 ]not/A/gr8'Place.2.store-mEyePassword[ 👀
Vehicles
MY21 J1 Premium RWD SR
Country flag
@janitorjim is absolutely correct. While neutral and ground are tied together, this is for bonding purposes. Your ground and neutral need to be at the same potential but for safety grounding. Technically, grounding is never needed for anything other than safety. The reason you tie them at one point, and only one point, is so there is no complete circuit to ground unless there is a fault. If you start connecting them at multiple places, you'll create ground loops which are bad.
Great explanation, both of you.

And happy to hear I did this correctly. ;) I installed a load center in my garage about 15 years ago and read the NEC at the public library while working through that... But definitely didn't understand everything. (Nor do I remember much now.)

Looks like my secondary load center has a fiber board to the right of the neutral bus/bar, which I assume is there to help prevent accidental ground loops, per your explanation.

Ford Mustang Mach-E Things to consider when DIY installing a wall charger / outlet PXL_20201128_201655766
Sponsored

 
 




Top