[US] - Over the Top - the well equipped EV home garage…for those that wish to "over do it"…

[daveo4EV]

At what length does "longer run" roughly start, where 3-wire cable and NEMA 6-50 receptacle should be considered?

cost - purely cost - copper wire is expensive these days - and your electrician will pull either 3 wire 6/8 gauge wire (hot, hot, ground) or 4 wire 6/8 gauge wire (hot, hot, neutral, ground) - depending on time of day, supply chain issues, wholesale vs. retail, inventory, time, temperature, DJ industrial averages, and number of butterflys in your garden - the cost for wire may vary wildly - and less wire tends to be cheaper than more wire so - given that there is infact 25% less wire in a 3 wire pull vs. a 4 wire pull - if you’re planning for 50 feet or more and there is a $1 difference per-foot - then you’ll save at least $75 pulling 75 ft of 3 wire bundle vs. a 4 wire bundle…

I have NO Problem pulling 3 wires vs. 4 wires - but I do recommend pulling higher amp gauge wire to allow for easy upgrades (at greater initial cost) in the future - it’s a one time cost of materials and labor - and while you may be installing a 40 EVSE today - you might want to upgrade to a 60 amp EVSE in few years and pulling this stuff again is both time consuming and expensive in terms of throwing away the old wire and purchasing new wire…

 

[daveo4EV]

right now on homedepot.com

50 ft of 10/2 wire (minimum gauge for 50 amps) - 3 conductor wire (2 hots + ground) is $126
50 ft of 10/3 wire (minimum gauge for 50 amps) - 4 conductor wire (2 hots, neutral, ground) is $173

so about a $1 foot

8 gauge is preferred for longer runs of 50 amps - and 8 gauge is physically “more” wire (thicker) than 10 gauge - so the cost difference should be greater

6 or 4 gauge would be preferred for “future proofing” but is overkill/over-design/over-specification for 240V/50 amps - and it will be even more expensive given that it’s even more materials…

if your electrician is charging you $950 to install your EV hook up 50 ft from your main panel

3 wire cost is $126 vs. 4 wire of $173 (today)
Hubble NEMA 6-50 plug is $85 vs. the crap $12 leviton plug
50 amp breaker (if they can find it these days) is another $20-$30
4x3x2 box for the NEMA plug is another $15

so total materials is AT LEAST 130+85+30+15 = $260‘ish in materials cost
4 wire pull would be $310’ish materials cost
for 50 feet of 10 gauge wire…

if it’s a 120 foot pull - well you get the idea - and if we up the gauge of wire from 10 to 6 gauge - well it could as much as $400 or more in terms of materials cost savings for 3 wire vs. 4 wire…

 

[Jhenson29]

At what length does "longer run" roughly start, where 3-wire cable and NEMA 6-50 receptacle should be considered?

Something else to consider, if it really is a longer run and you’re worried about future proofing, you may want to consider a larger feed to a sub panel for the longer run and then a shorter distribution to your receptacle.

My hardwired EVSE and separate receptacle are right next to a 125A subpanel fed from my main 200A panel. If I need different options in the future, I have 125A local in the garage to play with. (Maybe residential DC EVSE will become a thing and I can install a 24kW DC EVSE. ?)

 

[satchurator]

After multiple electricians ghosting me, my PWCC installation is finally happening on Tuesday. Detailed photos to come on another thread!

@daveo4EV It took quite a while but I finally got my PWCC fully installed! Here is my post for the unboxing and install, with photos and tips for other prospective buyers:
https://www.taycanforum.com/forum/threads/porsche-wall-charger-connect-unbox-install.7541

 

[daveo4EV]

@daveo4EV It took quite a while but I finally got my PWCC fully installed! Here is my post for the unboxing and install, with photos and tips for other prospective buyers:
https://www.taycanforum.com/forum/threads/porsche-wall-charger-connect-unbox-install.7541

i saw and reacted - what an awesome write up - nicely done!

 

[Tooney]

It seems like many EVSE boxes that plug into wall receptacles come with supply cables that are about 13 inches long. But I have seen one - Wall Wattz - that comes with a 6 foot supply cable.

I thought that the short length might be some electric code requirement.

The Pulsar 40 amp EVSE comes with 13 inch supply cable, but it says it can be hardwired instead, presumably with cable longer than 13 inches.

Why the use of 13 inch supply cables for plug-in units, longer plug-in cables for others, and longer hardwired supply cable lengths?

 

[daveo4EV]

It seems like many EVSE boxes that plug into wall receptacles come with supply cables that are about 13 inches long. But I have seen one - Wall Wattz - that comes with a 6 foot supply cable.

I thought that the short length might be some electric code requirement.

The Pulsar 40 amp EVSE comes with 13 inch supply cable, but it says it can be hardwired instead, presumably with cable longer than 13 inches.

Why the use of 13 inch supply cables for plug-in units, longer plug-in cables for others, and longer hardwired supply cable lengths?

no reason - a supply cable is just wire with a plug on the end - short cables are cheaper and 13” seems about right for positioning the charger vs. the plug - also the longer the cord the more “hassle“ it is to manage, hide, prop up or simply keep it out the way - also for 240V wire there are building codes to make sure it can’t be worn over time or exposed causing a short

keep in mind there is _NO_ functional difference between a hardwired eVSE and a “plug-based“ EVSE - and you can covert one to the other with simple and cheap parts from any home improvement store…it’s just a matter of how the EVSE vendor wants to provide the ‘default’ version of their product.

 

[Jhenson29]

no reason - a supply cable is just wire with a plug on the end - short cables are cheaper and 13” seems about right for positioning the charger vs. the plug - also the longer the cord the more “hassle“ it is to manage, hide, prop up or simply keep it out the way - also for 240V wire there are building codes to make sure it can’t be worn over time or exposed causing a short

keep in mind there is _NO_ functional difference between a hardwired eVSE and a “plug-based“ EVSE - and you can covert one to the other with simple and cheap parts from any home improvement store…it’s just a matter of how the EVSE vendor wants to provide the ‘default’ version of their product.

I believe this is incorrect per NEC 625.22. I don’t have time for more explanation at the moment, but look up that article.

 

[Klepper]

625.17 Cords and Cables. (9) (A) Power Supply Cord. The cable for cord-connected equipment shall comply with all of the following: (1) Be any of the types specified in (B)(1) or Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types in accordance with Table 400.4. Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types shall be listed, as applicable, for exposure to oil and damp and wet locations. Exception: A power supply cord that is listed as a part of the electric vehicle supply equipment or electric vehicle charging system. (2) Have an ampacity as specified in Table 400.5(A)(1) or, for 8 AWG and larger, in the 60 C columns of Table 400.5(A)(2). (3) Have an overall length as specified in (a) or (b): (a) When the interrupting device of the personnel protection system specified in 625.22 is located within the enclosure of the supply equipment or charging system, the power supply cord shall be no more than 300 mm (12 in.) long, (b) When the interrupting device of the personnel protection system specified in 625.22 is located at the attachment plug, or within the first 300 mm (12 in.) of the power supply cord, the overall cord length shall be a minimum of 1.8 m (6 ft) and shall be no greater than 4.6 m (15 ft).

 

[daveo4EV]

625.17 Cords and Cables. (9) (A) Power Supply Cord. The cable for cord-connected equipment shall comply with all of the following: (1) Be any of the types specified in (B)(1) or Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types in accordance with Table 400.4. Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types shall be listed, as applicable, for exposure to oil and damp and wet locations. Exception: A power supply cord that is listed as a part of the electric vehicle supply equipment or electric vehicle charging system. (2) Have an ampacity as specified in Table 400.5(A)(1) or, for 8 AWG and larger, in the 60 C columns of Table 400.5(A)(2). (3) Have an overall length as specified in (a) or (b): (a) When the interrupting device of the personnel protection system specified in 625.22 is located within the enclosure of the supply equipment or charging system, the power supply cord shall be no more than 300 mm (12 in.) long, (b) When the interrupting device of the personnel protection system specified in 625.22 is located at the attachment plug, or within the first 300 mm (12 in.) of the power supply cord, the overall cord length shall be a minimum of 1.8 m (6 ft) and shall be no greater than 4.6 m (15 ft).

so 13” (or 12”) is required for building code - cause they don’t want to much exposed wire…

so there is no function difference as I noted, but it’s a building-code/safety/requirements thing.

 

[Jhenson29]

so 13” (or 12”) is required for building code - cause they don’t want to much exposed wire…

Well, it’s not really about “exposed wire” as they allow supply cables up to 15’.

It’s about the proximity of the shock protection to the plug.

 

[ciaranob]

Well, it’s not really about “exposed wire” as they allow supply cables up to 15’.

It’s about the proximity of the shock protection to the plug.

@daveo4EV

OK, you guys just need to find an Electrician's closet - seriously - you're delving into some end member cable nerd stuff here Just kidding - kinda

 

[Jhenson29]

@daveo4EV

OK, you guys just need to find an Electrician's closet - seriously - you're delving into some end member cable nerd stuff here Just kidding - kinda

You mean you don’t have your own copy of the NEC (NFPA 70) at home to read at your leisure? ?

 

[Tooney]

625.17 Cords and Cables. (9) (A) Power Supply Cord. The cable for cord-connected equipment shall comply with all of the following: (1) Be any of the types specified in (B)(1) or Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types in accordance with Table 400.4. Hard Service Cord, Junior Hard Service Cord and Portable Power Cable types shall be listed, as applicable, for exposure to oil and damp and wet locations. Exception: A power supply cord that is listed as a part of the electric vehicle supply equipment or electric vehicle charging system. (2) Have an ampacity as specified in Table 400.5(A)(1) or, for 8 AWG and larger, in the 60 C columns of Table 400.5(A)(2). (3) Have an overall length as specified in (a) or (b): (a) When the interrupting device of the personnel protection system specified in 625.22 is located within the enclosure of the supply equipment or charging system, the power supply cord shall be no more than 300 mm (12 in.) long, (b) When the interrupting device of the personnel protection system specified in 625.22 is located at the attachment plug, or within the first 300 mm (12 in.) of the power supply cord, the overall cord length shall be a minimum of 1.8 m (6 ft) and shall be no greater than 4.6 m (15 ft).

I interpret this to mean that plug-in cords for EVSE can be 12 in or less, or can be from 6 to 15 feet long, depending on the location of "the interrupting device of the personnel protection system".
Is the "interrupting device" like a ground fault interrupter (GFI)?
If the Wall Wattz EVSE has a 6 foot plug-in cord, then its cord must have this device in the plug or within 12 inches of the plug?
And the standard above deals only with plug-in cords, not the length of hardwired supply connections?

 

[Jhenson29]

Disclaimer: I’m not an electrician.

I interpret this to mean that plug-in cords for EVSE can be 12 in or less, or can be from 6 to 15 feet long, depending on the location of "the interrupting device of the personnel protection system".

Yes, that’s how I understand it.

Is the "interrupting device" like a ground fault interrupter (GFI)?

Yes. From WallWattz installation manual:

And 625.22 (2017):

625.22 Personnel Protection System. The equipment shall have a listed system of protection against electric shock of personnel. Where cord-and-plug-connected equipment is used, the interrupting device of a listed personnel protection system shall be provided and shall be an integral part of the attachment plug or shall be located in the power-supply cord not more than 300 mm (12 in.) from the attachment plug. A personnel protection system shall not be required for supplies less than 60 volts dc.​

If the Wall Wattz EVSE has a 6 foot plug-in cord, then its cord must have this device in the plug or within 12 inches of the plug?

That’s my understanding. I have a 75A WallWattz, but it came with a 6’ LFNC and 6AWG THHN to wire, so I don’t know what the smaller plug-in ones look like, but their site says 6’ for the supply cables in all cases. So, you may want to call them if you have specific questions.

And the standard above deals only with plug-in cords, not the length of hardwired supply connections?

That’s also my understanding.