Installed ChargePoint Home Flex CPH50

[PV2EV]

Instead of stressing over the delivery and installation of the FCSP after I get the Lightning, I intend to install the ChargePoint Home Flex CPH50 in a secondary location. Later I will have an electrician install the FCSP in the primary location, in preparation for a future install of the HIS.

As a hardwired CPH50 requires 90c rated install for 50A charging, does anyone know if I can oversize the panel and breaker if they are rated at 75c? I plan to use 90c rated THHN 6g wire, a 70a (BR270) breaker, and a 125amp Eaton panel.

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[Maquis]

I think you misinterpreted something. There is no “90C install.”
What you are proposing is fine.

 

[EVBill]

Instead of stressing over the delivery and installation of the FCSP after I get the Lightning, I intend to install the ChargePoint Home Flex CPH50 in a secondary location. Later I will have an electrician install the FCSP in the primary location, in preparation for a future install of the HIS.

As a hardwired CPH50 requires 90c rated install for 50A charging, does anyone know if I can oversize the panel and breaker if they are rated at 75c? I plan to use 90c rated THHN 6g wire, a 70a (BR270) breaker, and a 125amp Eaton panel.

6 AWG wire is only good for 60 Amps maximum, so you cannot use a breaker larger than that.

 

[PV2EV]

To be clear, I had read "The CPH50 also mandates 90 °C conductors" and the included unclear text had me assume I had yet a third case of having to de-rate in two days. I forgot to de-rate for continuous load on an EVSE, I did not know to de-rate in a track-way/conduit over 24", and now I thought I had to de-rate/oversize the breaker and panel as they are only 75C rated.

In review, I can't find any requirement for 90C conductors from ChargePoint. Regardless, I am covered as 6 Gauge THHN is rated at 90c, which along with the 70A breaker is apparently the solution here.

Thanks for the input all.

 

[Maquis]

#6 THHN is only good for 65A, so I was incorrect saying you were fine in my first post. In theory, you could use the #6 at its 90C ampacity of 75A as long as you run metal conduit and transition to #4 in a junction box before it hits your panel. This is because the breaker terminals are only rated to accept 75C wire. No electrician I know would do a kludge like that.

 

[PV2EV]

Should we assume this requirement is bogus, as I can't find it from ChargePoint, the CPH50 can only land upto #6, and the only way to get the 50A output is to hardwire it?

50% at 125% is 62.5A, so the wire is fine. What about the breaker? 60A too small, 70A more than the wire. Maybe I need to set the EVSE to 48A instead of 50A?

Their support line was useless on this subject.

 

[Maquis]

Should we assume this requirement is bogus, as I can't find it from ChargePoint, the CPH50 can only land upto #6, and the only way to get the 50A output is to hardwire it?

50% at 125% is 62.5A, so the wire is fine. What about the breaker? 60A too small, 70A more than the wire. Maybe I need to set the EVSE to 48A instead of 50A?

Their support line was useless on this subject.

If you really want those 2 extra amps, the best, code-compliant way to do it would be to run #4 from your panel (75A breaker) to a junction box near the EVSE, and transition down to #6 for the last couple of feet.

If it were me, I’d set it to 48 on a 60A breaker. You’ll never notice the difference between 48 & 50A.

 

[FlasherZ]

The NEC works from the LOAD side of things, not the CAPACITY side.

50A load would require 62.5A circuit capacity due to continuous load (125%) rule. You need conductors rated for a minimum of that. #6 THHN in conduit will meet that requirement as it is good to 65A @ 75 degC terminations (since nearly every residential panel is rated for 75 degC terminations only).

It is legal to use the next size up breaker from the conductor ampacity if there is no standard trade size breaker for the load required and conductors used. So you can protect that branch circuit with a 70A breaker legally since there is no 65A breaker.

So yes, #6 THHN in conduit with 70A breaker would be appropriate for the CPH50. 6/3 and 6/4 NM-B cable ("Romex") is *not* legal as the use of NM-B requires you use the 60 degC column in the table.

 

[Maquis]

The NEC works from the LOAD side of things, not the CAPACITY side.

50A load would require 62.5A circuit capacity due to continuous load (125%) rule. You need conductors rated for a minimum of that. #6 THHN in conduit will meet that requirement as it is good to 65A @ 75 degC terminations (since nearly every residential panel is rated for 75 degC terminations only).

It is legal to use the next size up breaker from the conductor ampacity if there is no standard trade size breaker for the load required and conductors used. So you can protect that branch circuit with a 70A breaker legally since there is no 65A breaker.

So yes, #6 THHN in conduit with 70A breaker would be appropriate for the CPH50. 6/3 and 6/4 NM-B cable ("Romex") is *not* legal as the use of NM-B requires you use the 60 degC column in the table.

You are correct…I had a brain fart and forgot about the next size up allowance. Since the conductors are sufficient for the load (65>62.5), it’s compliant on a 70A breaker. The next question is does Eaton make a 70A BR breaker?

Edit: There is a 270 BR breaker. Good luck finding one these days!

 

[FlasherZ]

You are correct…I had a brain fart and forgot about the next size up allowance. Since the conductors are sufficient for the load (65>62.5), it’s compliant on a 70A breaker. The next question is does Eaton make a 70A BR breaker?

Yes they do. Part is BR270.

 

[Maquis]

Yes they do. Part is BR270.

Correct - I edited my post! Thanks

 

[jefro]

The manual for the EVSE is also part of the code. You have to follow what it says.

 

[PV2EV]

AWG 8 or 10 for ground wire? Seeing all the issues with the FCSP, I am glade I got the Flex as a secondary EVSE.

 

[PV2EV]

Wanted to update this thread with a pic of the completed install (I am missing one conduit clamp).

 

[FlasherZ]

AWG 8 or 10 for ground wire? Seeing all the issues with the FCSP, I am glade I got the Flex as a secondary EVSE.

Sorry - didn't see this question. 8 AWG copper required. NEC 250.122. 21-60A breaker = 10 AWG EGC, 61-99A breaker = 8 AWG, 100-199A = 6 AWG.

Wanted to update this thread with a pic of the completed install (I am missing one conduit clamp).

Nice install. I'm not always a fan of flex (except for things like motor connections) because of the droops-n-swoops, but you got it reasonably straight (something I have a difficult time doing without straight conduit lol).