Aluminum Wire for charging

[mike53north]

MYLR is on order, and need to get home charging set up. House was prewired for EV in the garage with #6 alum wire from panel to j-box through the wall, pulling copper is not really an option. Local utility will supply a ChargePoint Flex for almost nothing. The ChargePoint says copper only, as does the Hubbell 14-50R. Is there an industrial 14-50 receptacle rated for alum, or should I use a Polaris connectors and copper pigtails to hardwire the ChargePoint?

 

[zoomer0056]

Why is copper not an option?

 

[jjrandorin]

I am sure you will get some feedback from some of our more technical users, but in General, I would suggest transitioning from the aluminum to copper, in a code compliant manner. Whether thats polaris connectors or not I dont know, but I am sure someone will (know) what the right recommendation is.

 

[Sophias_dad]

Definitely need to transition to copper if you are connecting directly to the chargepoint.

Note that aluminum(50A) is rated lower than copper(55A), current-wise. Probably no big deal, you need to use no larger than a 50 amp breaker.

Even if you find an CU/AL outlet, you'll need to drop an extra hundred on a GFCI breaker(to be compliant, at least). This can probably be avoided for the hardwired case, at least if it were a Tesla HPWC it could.

 

[L_Mont]

When we build our house, we asked the electrician to pre-wired for EV charging in the garage. We did have an EV car at that time but all the electrical wiring is copper.
In the garage, he installed a service disconnect box, identical to the one for the 2 AC outdoor units. These boxes have screw type terminals and accept Copper or Aluminum wires. When I got the Tesla charger, I only add few feet of flexible watertight conduits and a copper wires.
Here is the type box: https://www.eaton.com/us/en-us/skuPage.AC222URNMP.html

If you have that type of box, maybe you are OK. On the copper wire, you may need to put anti-oxidation grease and torque accordingly.

 

[1100MCM]

I’m faced with a similar situation with the newly constructed home I moved into a couple of months ago. The builder pre-wired for EVs and they ran aluminum SER 6 AWG wire from the main panel right outside the garage up to the attic then across a few studs and then down along one of the wall cavities to a small junction box accessible inside the garage. The dilemma I have is either run the right wire (THHN 6 AWG copper wire) inside flex conduit following a similar path to the existing SER wire back to the main panel or just use the aluminum SER wire already in the wall. Of course the SER wire is stapled to the stud so it’s not like I can easily remove it and then run the new conduit and wire. I could just abandon the SER wire there and run the new conduit and copper wire parallel but it will be a lot of work.

Polaris connectors will be code compliant but keep in mind, at least the way it was in my case, the junction box they pre-installed will likely not be code compliant once you add 3 Polaris connectors in there with three wires entering the box and three wires exiting. Also that SER 6 AWG aluminum wire it’s pre-wired with is rated to 55 A (assuming that’s what you have) so you’re definitely going to be limited to a 50 A breaker, assuming the ChargePoint Flex can take that.

 

[mike53north]

Why is copper not an option?

New house, everything is behind sheetrock. I don’t want to do anything invasive while I still have the builders warranty, but I don’t want to wait a year to have at home charging. The aluminum is already in the walls, so I’m just looking for the best way to utilize it.

 

[MY-Y]

New house with 6 gauge aluminum? That's not cool. I understand using aluminum for feeding panels (e.g. 2/0), but for an EV???

 

[Sophias_dad]

New house with 6 gauge aluminum? That's not cool. I understand using aluminum for feeding panels (e.g. 2/0), but for an EV???

Its a matter of money. #6 copper is $0.86 a foot. #6 aluminum is 0.52 a foot. That extra $0.34 a foot (mulitplied by three or four conductors) turns into profit for the builder. Not his/her fault that the specification was incomplete.

 

[ucmndd]

You can’t terminate aluminum directly in the wall connector or ChargePoint. Don’t do it. So yeah, if you want to use the existing wire, you need to transition to copper.

 

[snellenr]

MYLR is on order, and need to get home charging set up. House was prewired for EV in the garage with #6 alum wire from panel to j-box through the wall, pulling copper is not really an option. Local utility will supply a ChargePoint Flex for almost nothing. The ChargePoint says copper only, as does the Hubbell 14-50R. Is there an industrial 14-50 receptacle rated for alum, or should I use a Polaris connectors and copper pigtails to hardwire the ChargePoint?

Google coughed up a Cooper 5754N 14-50R which lists aluminum compatibility - looks like an Eaton product. No idea of quality, but pricing is higher than the big box store Leviton stuff, FWIW...

Link to what I found...

 

[h2ofun]

I’m faced with a similar situation with the newly constructed home I moved into a couple of months ago. The builder pre-wired for EVs and they ran aluminum SER 6 AWG wire from the main panel right outside the garage up to the attic then across a few studs and then down along one of the wall cavities to a small junction box accessible inside the garage. The dilemma I have is either run the right wire (THHN 6 AWG copper wire) inside flex conduit following a similar path to the existing SER wire back to the main panel or just use the aluminum SER wire already in the wall. Of course the SER wire is stapled to the stud so it’s not like I can easily remove it and then run the new conduit and wire. I could just abandon the SER wire there and run the new conduit and copper wire parallel but it will be a lot of work.

Polaris connectors will be code compliant but keep in mind, at least the way it was in my case, the junction box they pre-installed will likely not be code compliant once you add 3 Polaris connectors in there with three wires entering the box and three wires exiting. Also that SER 6 AWG aluminum wire it’s pre-wired with is rated to 55 A (assuming that’s what you have) so you’re definitely going to be limited to a 50 A breaker, assuming the ChargePoint Flex can take that.

why are the polaris connectors an issue?

 

[1100MCM]

why are the polaris connectors an issue?

The junction box needs to be sized properly. This depends on the number of wires entering and exiting the box along with the size of wire.

 

[davewill]

Rather than Polaris connectors I'd probably get a small load center and do the transition there. Would allow a load sharing setup later, and give a local disconnect.

 

[mike53north]

Its a matter of money. #6 copper is $0.86 a foot. #6 aluminum is 0.52 a foot. That extra $0.34 a foot (mulitplied by three or four conductors) turns into profit for the builder. Not his/her fault that the specification was incomplete.

Yeah, the builder advertised the development as EV ready, but at that time I hadn’t looked into the ins and outs of hooking up the EVSE.

 

[qdeathstar]

Just put a disconnect on the wall in place of the junction box then copper whip it to the charge point

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The Square D by Schneider Electric QO 60 Amp 240-Volt 7.5 kW Non-Fused Air Conditioner Disconnect is UL listed for residential, commercial and industrial power distribution. QO AC disconnects are the "World's Finest" and designed with industry leading features for flexible application. The...

www.homedepot.com

 

[tangible1]

Okay, as a lazy but cost-friendly idea, you could just limit your charging current to the code-compliant level for continuous load on #6 aluminum.

It will take a little longer to fully charge, but since most charging occurs overnight, I'm pretty sure it will still be sufficient to meet your needs.
8 hours or so should be more than enough time to top off the car overnight.

 

[jjrandorin]

Okay, as a lazy but cost-friendly idea, you could just limit your charging current to the code-compliant level for continuous load on #6 aluminum.

It will take a little longer to fully charge, but since most charging occurs overnight, I'm pretty sure it will still be sufficient to meet your needs.
8 hours or so should be more than enough time to top off the car overnight.

Limiting the charge isnt the question in this thread. Its "how do I connect my wall connector or outlet, in a code compliant manner"?

 

[davewill]

Okay, as a lazy but cost-friendly idea, you could just limit your charging current to the code-compliant level for continuous load on #6 aluminum.

It will take a little longer to fully charge, but since most charging occurs overnight, I'm pretty sure it will still be sufficient to meet your needs.
8 hours or so should be more than enough time to top off the car overnight.

He has to do that anyway unless he replaces all the aluminum with copper.

 

[L_Mont]

Just put a disconnect on the wall in place of the junction box then copper whip it to the charge point

.

Square D QO 60 Amp 240-Volt 7.5 kW Non-Fuse AC Disconnect QO200TRNM - The Home Depot

The Square D by Schneider Electric QO 60 Amp 240-Volt 7.5 kW Non-Fused Air Conditioner Disconnect is UL listed for residential, commercial and industrial power distribution. QO AC disconnects are the "World's Finest" and designed with industry leading features for flexible application. The...

www.homedepot.com

This is exactly what I suggested in post #5. Looking closely at the picture in this brochure, the wires to the disconnect box are Al and the wires out are Cu.

https://www.eaton.com/ecm/idcplg?IdcService=GET_FILE&allowInterrupt=1&RevisionSelectionMethod=LatestReleased&noSaveAs=0&Rendition=Primary&dDocName=PA00701002E