Level 2 at Home Idea

[louc757]

I wanted to use the 50amp EVSE to get the fastest charge I could at home. I understand that is limited to 48amp, but 50amp will get there.
From there, my understanding is that a 48-50amp EVSE has to be hardwired.

The idea was simply a way to try and have my cake and eat it too. LOL
Hardwired EVSE and option to have a 14-50 plug, while only having room for one or the other in my breaker box. If I had spots for another double breaker, I'd just do that. I could have a second breaker added, but now we're adding more $$, more space on the wall, etc.

I have a similar issue. I have an Emporia 48A EVSE and wanted a NEMA 14-50 plug as a backup. Since I only have 1 spot for a 220V CB in the service panel, I elected to install a 100A sub-panel in the garage. I have two 150A main panels. This way I’m up to code by each charger having its own dedicated circuit, and I have the backup (or get a welder or lathe if I can convince the wife!). +1 on using some cheap Chinese switch from AZ. This is more expensive, but with almost 50A continuous being pulled from the circuit, you want a quality install.

Sponsored

 

[mjs020294]

I did *NOT* know these existed. At our vacation house, the panel is full, and already has some tandem single slot breakers. I will be looking to see if I can swap in one of these to get a 240V outlet in the garage.

Thank you for posting.

You can only install tandem breakers is a few slots on a panel: Usually the bottom few on each bar.

 

[mjs020294]

Most people park their cars for 10-12 hours a day so a 32AMP charger is more than sufficient for 95% of people.

 

[devmach-e]

You can only install tandem breakers is a few slots on a panel: Usually the bottom few on each bar.

My panel disagrees with you. And yes, this has passed inspection, multiple times.

 

[mjs020294]

My panel disagrees with you. And yes, this has passed inspection, multiple times.

A few points. Firstly you seem to have reading comprehension issues because my post clearly states "usually" which means its not a hard rule.

Passing inspection is not proof of the specification of a panel. My panel is model number HOMC30UC (which is not designed for tandems) and it to has passed multiple inspections with tandem breakers present. If the panel was designed to take tandems the model would be something like HOMC2436UC (24 being slots and 36 indicating maximum breakers allowed).

BTW - I wouldn't put a EV charger on a tandem breaker. It would be better putting four 15/20 circuits on a couple of tandems to clear space for a traditional breaker for the EV.

 

[Nemy]

BTW - I wouldn't put a EV charger on a tandem breaker. It would be better putting four 15/20 circuits on a couple of tandems to clear space for a traditional breaker for the EV.

I agree. This would take up the same space and leave a dedicated breaker for the EVSE. Plus if OP wants his "cake," he'd need a 60 amp breaker.

 

[DadzBoyz]

BTW - I wouldn't put a EV charger on a tandem breaker. It would be better putting four 15/20 circuits on a couple of tandems to clear space for a traditional breaker for the EV.

I like this idea.... if the breaker is compatible.

 

[Mach-Lee]

You can only install tandem breakers is a few slots on a panel: Usually the bottom few on each bar.

Depends on the panel. Some panels you can put them anywhere. But yes you should look at the digram inside to see where they are allowed.

BTW - I wouldn't put a EV charger on a tandem breaker. It would be better putting four 15/20 circuits on a couple of tandems to clear space for a traditional breaker for the EV.

Yes, this is the better way to do it if possible.

 

[DadzBoyz]

I agree. This would take up the same space and leave a dedicated breaker for the EVSE. Plus if OP wants his "cake," he'd need a 60 amp breaker.

Actually, was thinking 65-70, if possible.
I figure overdoing it may be safer.
The EVSE has an internal GFCI too.

 

[mjs020294]

Depends on the panel. Some panels you can put them anywhere. But yes you should look at the digram inside to see where they are allowed.

I said "Usually the bottom few on each bar."

 

[devmach-e]

A few points. Firstly you seem to have reading comprehension issues because my post clearly states "usually" which means its not a hard rule.

Passing inspection is not proof of the specification of a panel. My panel is model number HOMC30UC (which is not designed for tandems) and it to has passed multiple inspections with tandem breakers present. If the panel was designed to take tandems the model would be something like HOMC2436UC (24 being slots and 36 indicating maximum breakers allowed).

BTW - I wouldn't put a EV charger on a tandem breaker. It would be better putting four 15/20 circuits on a couple of tandems to clear space for a traditional breaker for the EV.

My panel is specifically made to support tandem breakers. I've had to have the electrical panel inspected in depth several times since it was installed 23 years ago when we bought the house. It originally came with a 60A fuse box. First thing we did was hire an electrician to upgrade things and clean-up the crappy wiring job the previous owner did. Which included installing tandem breakers in some locations. Then again when we added solar, and again after a kitchen remodel.

My panel is a Murray LC012DC if you care to look it up. Specifically says 12 spaces, 24 circuits.

Not sure why I need a dedicated 40A breaker taking up two spaces for an EVSE. This has been in place for 10 years. And as I said, passed inspection when the EVSE was installed. Electrician did a load calculation at the time and the inspector signed off.

 

[Jimrpa]

I am not a licensed electrician:

There, now that’s out of the way. You’re already spending the bucks on an EVSE and having it hardwired. Just go ahead and eat the additional cost to get an additional dedicated circuit to an industrial 10-50 plug installed while the electrician is there. The incremental cost won’t be much more than what you’re proposing with the switch, even if the electrician has to rearrange some breakers to make room or, gasp, put in a bigger panel or a sub panel. Just do it right from the start.

 

[satchel prefect]

Most people park their cars for 10-12 hours a day so a 32AMP charger is more than sufficient for 95% of people.

This. I run my hardwired EVSE at 24A (half of what it's capable of and wired for) and it's enough for 2 cars. (Typical daily consumption is 5-10 kwh per car or 1-2 hours of charging: 24Ax240V~5KW.)

No doubt, there are legitimate needs for the quickest charging possible. Having said that, I think it bears considering that like DCFC, there is a point of diminishing returns with home charging speed. This is especially true for overnight charging.

If the car is parked for the night, does it really matter if it charges in 3.5 hours instead of 5? Mind you, 5 hours at 32A will replenish around 35 kwh which should be at least in the 90 mile range assuming a modest 2.5 mi/kwh driving efficiency.

 

[generaltso]

Actually, was thinking 65-70, if possible.
I figure overdoing it may be safer.

Larger breakers don’t make it safer. It just makes you use larger and more expensive wire.

 

[dtbaker61]

These exist if you're out of room:

the problem with adding TWO new 50 amp circuits, which *could* be used at the same time is that you might exceed the total possible load rating on the main service.

You *could* solve that by adding a small (60amp) sub-panel and putting both the EVSE and outlet circuit in the subpanel with a Generator transfer switch that would prevent both from being used at the same time.

either way, redundancy is going to cost you.

A well installed 14-50 outlet, with a 50amp breaker and 6/6/6w8g wire, and plug-in EVSE with charge current limited to 32amps will be a fine way to go. If the EVSE fails, you pull out your Mobile charger and use it.....

Sponsored