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HPWC Installed

ATPMSD

Member
Mar 12, 2021
459
442
Atlanta, GA
The EVSE will draw the maximum current from the circuit for the duration of the charging period that could last more than 8 hours.

Do you have a source you can share? Every place I look sells extension cords designed for EVSEs, and of course the TWC will use of 80% of the circuit rating which is well within specs. And the OP just noted it passed inspection. Maybe the code is much sticker where you live?
 

jcanoe

Active Member
Oct 2, 2020
3,873
3,954
Maryland
As to whether the power plug pigtail is a) allowed by code or b) too long (more than 12 inches total length) I don't have a source, rely on what others with more experience have stated.

You could use a handheld digital thermometer (under $20 on Amazon) and measure the approximate temperature of the power plug, cord and charging cord connector. Check this when charging at 40A and also when charging at 32A (you can set this on the Tesla charging screen.) You might decide that the setup runs sufficiently cooler at the lower amperage setting to permanently configure the Wall Connector for a 40A circuit and 32A charging.
 

jcanoe

Active Member
Oct 2, 2020
3,873
3,954
Maryland
Do you have a source you can share? Every place I look sells extension cords designed for EVSEs, and of course the TWC will use of 80% of the circuit rating which is well within specs. And the OP just noted it passed inspection. Maybe the code is much sticker where you live?
Extension cords with NEMA 14-50 plug and receptacle connectors could be used for RVs. All of the EV vehicle manufacturers state that extension cords should not be used to charge the vehicle.
 
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jcanoe

Active Member
Oct 2, 2020
3,873
3,954
Maryland
Respectfully there is a difference between should not and can not. The reason they say should not is for legal reasons.
You stated "Every place sells extension cords designed for EVSEs." Extension cords are not designed for EVSEs, I don't believe an extension cord manufacturer would make this claim.

You can stand above the second step on a step ladder too but that does not make it smart or safe.
 

TMYP

Member
Aug 28, 2021
6
1
california
I just installed my WC (with a cord) and the install was super easy on an existing NEMA 14-50 outlet, wired a 50 amp appliance cord to it, and set the amps to 50. Charges at 9 kWh/40 amps @ 36 mph and I keep my NEMA 14-50 outlet.

UMF2qJO.jpg


I do wish the cord was longer than 18', where I originally had the outlet installed was based on a Clipper Creek EVSE that had a 24' cord. My parking is now limited. Oh well, first-world problems.

I am confused by one thing, the included Quickstart Guide indicated the LED lights correspond to the amperage settings, 5 LEDs = 60A, 4 LEDs = 50A etc. But when my unit is charging ALL 5 led's light up. The unit was successfully commissioned via WI-FI and set to 50A and the car's display shows it's pulling 40A/9 kWh @ 36 mph.
Do you have a link to the cord that you used, i am assuming any 14-50 nema cord with at least 6g wire will do the job
 

MY-Y

Active Member
Mar 4, 2020
1,158
1,302
MD
...

You could use a handheld digital thermometer (under $20 on Amazon) and measure the approximate temperature of the power plug, cord and charging cord connector. ...
Many will be surprised if they measure Temps.

At 48 amps, the loop cord of my Tesla HPWC hits 125. The top, if two coils touch, hits 141 degrees. (I use only a single big loop now.)
20200719_143509.jpg
20200923_125617.jpg


With my 14-50 on my Juicebox for my other EV, the plug would hit 186 degrees at 32 amps with my cheap Leviton plug, and 154 when I took Rocky's advice to install a Hubbell outlet. Clearly, charging an EV isn't something to push the limits of code with.
20200922_210338.jpg

20200922_210228.jpg
 

ATPMSD

Member
Mar 12, 2021
459
442
Atlanta, GA
@TomServo

Here is an idea, but first also consider that on page 2 of TWC manual it states

WARNING: The Wall Connector must be grounded through a permanent wiring system or an equipment-grounding conductor.

this means you cannot use just a plug, at least that is how I read it. Here is my suggestion:

Relocate the TWC to where you would really like it to be. Then hire an electrician to run a line from the TWC to the outlet box and make it a hardwire connection instead of a plug. I suggest an election for three reasons: 1) it really should not cost much, 2) you can ensure it is done to code and 3) I would have the electrician check the wiring from the breaker box to the outlet to see what wire was used. If you are very lucky they will have used a wire capable of supporting a 60-amp circuit, which would mean you will get full power from the TWC. This is a long shot.

Good luck!
 
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TomServo

Active Member
Apr 10, 2014
1,663
1,096
Belleville IL
I'm not an electrician nor have I stayed at a Holiday Inn but I still have unanswered questions, please bear with me.

The entire circuit (breaker to wall plate) is wired with 6 awg wire. Here's a look at the wall plate after the power cord was installed. It's exactly 24" from the connectors to the plug.
XGCvnnQ.jpg


Wouldn't that be exactly the same had it been "hard-wired"? If so how would that impact the WC? How is the better?

Re the plug, I purchased a 4 ft GE 50 amp appliance cord (made in the Philipines and not China if that matters) plugged into a NEMA 14-50 wall plug and protected by a 50 amp breaker installed 2.5 years ago when my house was built.

Can someone please explain where and how ANY issue will manifest itself?

How would this be different if I call the electrician and have him remove the plug and "hard-wire" the WC to my circuit? He'll still need to run 6 awg wire from the former outlet (making some kind of joint at that point I assume) and connect that wire to the wall plate.

Lastly, I'm prepared to call my electrician back and either: shorten the cord to 12" or hard-wire it to the outlet box. But I'm struggling to understand how hardwiring with a second junction is any safer than the cord?

Thanks in advance.
 

EVer Hopeful

Member
Jul 7, 2021
599
472
Texas
Well for one thing, you've got a bottom entry but feed the connectors also from the bottom. The book says run them up the side and use the top of the connectors

1630506866534.png



And remember that a 50A power cord is really meant for an appliance that cycles on and off, not for an EV with several hours of continuous charging

but probably what they're really getting at is that an outlet and a plug are an interface, whereas hardwiring is no-interface. Sure an outlet and a plug are a normal way of connecting things, but they're not as 'solid' as a wire nut or a kearney or a bus bar
 
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ATPMSD

Member
Mar 12, 2021
459
442
Atlanta, GA
Wouldn't that be exactly the same had it been "hard-wired"? If so how would that impact the WC? How is the better?
This really all boils down to electrical "code." what the TWC manuals says and, lastly, what you as the owner find as acceptable. Some will point out that if you have a fire caused by the installation, and it is not code, an insurance company can deny a claim. But if the outlet was installed by a builder or an electrician then perhaps you have a good case.

How would this be different if I call the electrician and have him remove the plug and "hard-wire" the WC to my circuit? He'll still need to run 6 awg wire from the former outlet (making some kind of joint at that point I assume) and connect that wire to the wall plate.

Same comment as above. Note that 6-guage wire is limited to 55-amp unless the wire used is rated to 90°C, in which case it will support 60-amps+. But this is the domain of a qualified electrician.
 

Sophias_dad

Active Member
Supporting Member
Jul 29, 2018
1,710
1,802
Massachusetts
Thanks, I'm calling the electrician and will remove the cord and hard wire it. Am thinking I should have just kept the Clipper Creek.
While its not supposed to be done, I myself would be fine with the cord at 40 amps continuous(assuming the 14-50 was really wired for 50 amps!) Just sayin'.

Regarding the HPWC manual saying the conductors should go up and around or down and around, I suspect that is to have some extra conductor in case it needs to be redone at some point. For your corded case, it doesn't matter at all because you can just buy another cord if it gets too short in the base. The only other reason I can think of that they might want the extra conductor is to give the conductor some 'wiggle' room as it heats/cools during charging, rather than forcing it back through conduit.
 

with_raiden

Member
Apr 11, 2021
227
199
NYC
I refuse to deal with the ~18.5 ft charging cord.
The Wall Connector is now available in 24 ft 😊.

 

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