Wall charger wire gauge question

[beatle]

Still not worth it.

Keep in mind that if you're using Romex and not THHN in conduit, this is just good for a 50A circuit for 40A charging. You need to drop to 4awg if you're using Romex and want to put it on a 60A circuit. Not worth the increase just for 20% faster charging IMO. 40A charging is plenty. Being that this is in a garage of a high rise, he's probably using conduit anyway.

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[Greg Chick]

Your electrician isn't wrong, he's doing the right thing by considering voltage drop. But in your case it's not significant. #6 at 1.42% voltage drop is still well under NEC maximum of 3%. Considering that #4 costs more and if done right, he needs provide approved transition from #4 to #6 which will also add to the cost.

I would measure the line voltage at the panel. It may be higher or lower than than 240v. I'd just go with #6 as long as the line voltage is at least 238 volts at the panel.

I have used stranded wire and cut off a few strands to fit the terminal. Also once the stranded wire fits in, pulled it out and soldered it to the shape that fits then reinserted it and clamped tight. Also, I have put my load on it, them tested the voltage drop to see that it is above the Min.
Another point is using a new breaker that is top grade listed for EV or long load not just 10 min. load.

 

[therealcmj]

I have used stranded wire and cut off a few strands to fit the terminal. Also once the stranded wire fits in, pulled it out and soldered it to the shape that fits then reinserted it and clamped tight.

That seems very not good. Like very very.

 

[R1S88]

Still not worth it.

Keep in mind that if you're using Romex and not THHN in conduit, this is just good for a 50A circuit for 40A charging. You need to drop to 4awg if you're using Romex and want to put it on a 60A circuit. Not worth the increase just for 20% faster charging IMO. 40A charging is plenty. Being that this is in a garage of a high rise, he's probably using conduit anyway.

I'm pretty sure it's THHN in conduit, but would stress that I would be very happy to have 20% faster as cost is not a consideration in this specific case. Thanks

 

[Zoidz]

I have used stranded wire and cut off a few strands to fit the terminal. Also once the stranded wire fits in, pulled it out and soldered it to the shape that fits then reinserted it and clamped tight. Also, I have put my load on it, them tested the voltage drop to see that it is above the Min.
Another point is using a new breaker that is top grade listed for EV or long load not just 10 min. load.

Yes, that's a common work around. Yes, it's very low risk of any complications. But ... if the installation gets inspected, that technique violates several sections of NEC Article 110 and should/would fail inspection by a competent electrical inspector. There are reducing splice fittings/terminals made for this purpose.

 

[Greg Chick]

Yes, that's a common work around. Yes, it's very low risk of any complications. But ... if the installation gets inspected, that technique violates several sections of NEC Article 110 and should/would fail inspection by a competent electrical inspector. There are reducing splice fittings/terminals made for this purpose.

I have seen the copper ones, that would be Much better, I agree. Again, imposing full load, then measuring the volt insuring the drop is minimal and within code.

 

[beatle]

Yes, that's a common work around. Yes, it's very low risk of any complications. But ... if the installation gets inspected, that technique violates several sections of NEC Article 110 and should/would fail inspection by a competent electrical inspector. There are reducing splice fittings/terminals made for this purpose.

I've also done it the hacky way on car stereo installs, but yes, these are better:

https://www.elecdirect.com/lug-comp...educing-crimp-splice-4-awg-gray-to-6-awg-blue

I'm pretty sure it's THHN in conduit, but would stress that I would be very happy to have 20% faster as cost is not a consideration in this specific case. Thanks

Oh for sure, if he's already doing 6awg THHN in conduit, might as well charge at 48A.

 

[Zoidz]

I have seen the copper ones, that would be Much better, I agree. Again, imposing full load, then measuring the volt insuring the drop is minimal and within code.

An inspector could fail the trimming technique for several code violations:
- The EVSE specifies acceptable wire size range for the termination. The attached wire indicates #4, outside of the EVSE specified design range
- The wire indicates #4 on the jacket, trimming compromises the integrity of the jacket label vs wire ampacity. A future person could install a larger breaker and load requiring #4 with potential consequences.
- They can fail if they see the stripping technique has damaged the conductor. I've seen them do this on solid wires that are nicked while stripping. Picky, yes, but they can and will fail it.

I'm not finding fault with anyone doing this, just pointing out the possible issues that could come up if the installation is inspected.

 

[Zoidz]

Update: I was given a more accurate measurement and it’s actually 130 feet. I suspect the answer is still to go with 6 awg, but thought I would ask the experts here to be sure. Thanks!

Still within NEC under 3%, I would run #6 and avoid the other issues.
Or..... go bigger by installing a 100A subpanel if there is the possiblity of future loads, and then that easily transitions to a short #6 for your EVSE. That was my solution. I now have a 100A subpanel in the garage.

 

[Greg Chick]

An inspector could fail the trimming technique for several code violations:
- The EVSE specifies acceptable wire size range for the termination. The attached wire indicates #4, outside of the EVSE specified design range
- The wire indicates #4 on the jacket, trimming compromises the integrity of the jacket label vs wire ampacity. A future person could install a larger breaker and load requiring #4 with potential consequences.
- They can fail if they see the stripping technique has damaged the conductor. I've seen them do this on solid wires that are nicked while stripping. Picky, yes, but they can and will fail it.

I'm not finding fault with anyone doing this, just pointing out the possible issues that could come up if the installation is inspected.

Good points

 

[Tlohrenz]

That 130 ft distance requires 5 gauge, so you'll need 4 gauge copper. You can run 4 gauge wire to a small 2 or 4 space sub-panel. Then 6 gauge to the charger. That will pass anyone's code and give you max voltage.
this is what I ended up doing.

 

[Conseil]

Your electrician isn't wrong, he's doing the right thing by considering voltage drop. But in your case it's not significant. #6 at 1.42% voltage drop is still well under NEC maximum of 3%. Considering that #4 costs more and if done right, he needs provide approved transition from #4 to #6 which will also add to the cost.

I would measure the line voltage at the panel. It may be higher or lower than than 240v. I'd just go with #6 as long as the line voltage is at least 238 volts at the panel.

@Zoidz Where can I find this app?

 

[Zoidz]

@Zoidz Where can I find this app?

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