Newbie home charging question

H

Hi_Fi_Guy

New Member
My wife and I are finally ready to make the leap from ICE to EV. We are going to look at VW ID.4s and I have been trying to figure out the home charging situation.

Our garage has a dryer style 240v/30a plug however it is the older NEMA 10-30 connector. I have found several NEMA 10-30 to NEMA 14-50 adapter cables on Amazon to allow a Level 2 home charger to connect to power.

So the big question is about Amps. It looks like most of the home chargers are looking for 32-40 amps and I know my 30amp outlet is only capable of about 24amps continuous. Will the Level 2 chargers work with this lower amperage? Does the level 2 charger or the ID.4 itself have a way to set the charge to 24amps to protect the circuit from overloading?

We are looking at the Level 2 home charger from Electrify America because it supposedly works with their app. Is it worth it? Will it work? Or are some of the units available from Amazon a better fit for our situation?

HomeStation - Level 2 Home Charger from Electrify America
https://www.electrifyhome.com/homestation
 
I'm in a similar situation - 30 A circuit to a garage (with buried cable from the house so not easy to upgrade). There are one or two level 2 chargers (sorry, can't recall off-hand what the brand name is but you can google it) that will supply 24 A only and some that are adjustable which might be the better buy as you may want to upgrade to a higher capacity circuit later.

One question I have with the adjustable models is do you have to replace the plug (if present) with a 30 A or, can you install a higher amperage receptacle (on the 30 A circuit) to go with the plug it comes with (I doubt that would meet code though)?

As well, if you have a wired in (no plug) adjustable unit, can you legally wire it to a 30 A circuit (with the unit set to 24 A)?

It bums me BTW that we seem to be dependent on forums to get information such as this as the dealerships usually know nothing about such details and writing to the manufacturer usually results in no reply (in my experience at least).
 
Laurie Forbes said:
I doubt that would meet code though
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You have answered your own question.
An electrical contractor wiring under permit must match the capacity of the supply circuit and meet the maximum load requirements. If the load is adjustable, it must be assumed it will be used at it's maximum capacity.
With your existing wiring assuming it is #10 AWG (30A), maximum continuous load = 24A, which must be the rating of the equipment.
If you want to go higher, I would run a new #6 AWG copper cable (Teck or NWWU). At that point you could have the unit hardwired (best) or have the electrician install a 14-50 receptacle which would match the majority of EVSEs out there.
The actual receptacle could be a 6-50 as EVSEs do not require the neutral connection, but they are manufactured that way for RV parks connections, so best to stay that way.
The #6 Teck 90 while rated @ 65A ( table 2,75 degree column) could be protected by a 70 A breaker (table 13) which would be capable of supplying a 13.4 kW load (56A) max, that being below the 65 A cable rating.
NMWU is only rated @ 60 degrees (55A) so your breaker would have to be reduced to 60A giving you a 48 A max (11.5 kW).
I have not allowed for main service capacity nor any voltage drop in above scenarios which may have to be additionally calculated depending on the distance.
There are no GFCI CLASS A requirements if installed indoors (garage), if outdoors and within 2.5 meters of grade, it must be class A gfci protected (if it is a receptacle) - no gfci requirements in Canadian code (yet) for outdoor hardwired equipment.
Hope that helps, didn't want to be too technical;)
 
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electriceddy said:
You have answered your own question.
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Hey, many thanks for a detailed and informative reply. Looks like I would have to go with the 24 A charger as, noted previously, I am kinda stuck with a 30 A service. Actually, that would meet my particular needs very well so no prob.

Am wondering though why you feel hardwired is best as a plug-in unit is easily portable and, in the usual scheme of things, would not have to be plugged/unplugged very much at all.
 
Laurie Forbes said:
Am wondering though why you feel hardwired is best as a plug-in unit is easily portable and, in the usual scheme of things, would not have to be plugged/unplugged very much at all.
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Sometimes plugs fail - excessive resistance can cause the plug to melt. Probably a rare occurrence, but it does happen. I think it happened to Bob Wilson not that long ago. I think the theory is that this is less likely when hardwired.
 
Yeah, electric ranges and clothes dryers are typically (always?) plugged in and you rarely hear of issues. I wonder what most folks go with? Personally. I wouldn't loose any sleep over a plug-in charger (especially in the case of the OP with an existing dryer receptacle).
 
Dryers, ovens and ranges generally are used for short periods of time and cycle on and off during operation so the load is not continuous putting less stress on the plug connection. Where as an EVSE runs at full load (80% of breaker) for usually 8 to 10 hours putting significantly more stress on the a plug. Hard wired is best. That said I have a 14-50 plug on my EVSE. ;)
 
Fastnf's reply re: duty cycle is right on the mark.

Few home appliances - even the high-current ones - draw at or near their max rated current continuously for extended periods.

Continuous current draw allows heat to build-up in the wiring and cause failures at "weak points" - failures which might never occur with "normal" intermittent duty loads.

One never knows what "jury rigs" and "band-aids" might have been installed in existing residential circuits over the prior years/decades; or if they were even installed properly to begin with.

I wouldn't consider installing EVSE on any existing circuit w/o a thorough check-out of the entire circuit. (meaning opening every J-box and checking every termination). This includes 120 VAC AC Level 1 EVSE as well.

Of course, this "checkout" can be expensive (especially if you find a "problem"); it's generally better/cheaper/faster to simply install a brand-new circuit of known quality - to either a hardwired EVSE or to a new EVSE receptacle.

Remember, AC charging often occurs at night and while unattended; by far the most dangerous time for a residential fire.
 
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Good points about the higher continuous loads but isn't the 80% rule supposed to address that issue?

In any case, plug-ins for this application are code compatible....
 
Laurie Forbes said:
... isn't the 80% rule supposed to address that issue? ...
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Yes it is.

It's established to account for minor installation variations and aging in otherwise properly-installed configurations.

However, with DIY stores and YouTube having made "everybody" feel "fully qualified", there's a lot of NOT properly-installed wiring; especially in residential where it "accumulates" literally for decades.

No need to cite examples, but I don't think anyone here would really dispute the premise.

While even improperly installed wiring may indeed work safely for years w/o trouble in low-load / intermittent conditions; taking it to 80% for hours on-end can be problematic.
 
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I researched the heck out of it and managed to get a real deal on an install of a NEMA-14-50 output in my garage by a local electrician (only $300.00). Of all the manufacturers of the EVSE's out there (and there are a number of them) I went with perhaps the most respected of them all. The Clipper Creek. I went with their model 50P which is a 40amp 9.6kw unit designed for use with a 50amp breaker which is what I had installed. Love the wonderful speeds it provides in the charge process. I've never had to wait more than several hours for a full top up. Often from around 40% to 90%. The cable doesn't even get warm in the process and the unit is very nicely made with it's built in cable hang design. It was $650 but worth every penny. You bet I'll take the tax deduction that remains in place for those installed through December of 2021.
 
I have a 2018 Honda Clarity PHEV which, on average, has a 50 mile EV and 300 mile HV range with its tiny 7 gallon gas tank. What I have learned is that most days could be done on all EV. Even with occasional longer trips I learned that ok to not have 200+ miles range available at the beginning of every day. I learned my current 16 amp level 2 EVSE would probably be all I would need if I went full electric. The 16 Amp 240 volt level 2 restores 12.5 miles of range an hour. A 32 amp EVSE adds 25 miles of range an hour. Both 16 amp and 32 amp can easily be used on a 50 amp Nema 14-50 with plenty of extra margin of safety. So if you top up everyday with a 32 amp EVSE the amount of miles that can be restored while home is more than enough for most people’s daily drive without stressing anything electrical even if there is a day when you don’t start off with the maximum range.
 
The Gadgeteer said:
... I learned that [it's] ok to not have 200+ miles range available at the beginning of every day...
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A nice post, thanks.

I think many potential EV purchasers underestimate how long their vehicle will actually be "garaged" and on-charge.

Some of this is probably due to EVSE marketing (i.e. reinforcing the "bigger/faster is better" mindset) and the apples-to-oranges comparison w/ DC fast charging (where one generally DOES want to minimize "on-pad" duration).

As you clearly demonstrate, even "lower-rate" AC Lvl-2 charging can add significant kWH into to a battery overnight and meet many (if not most) routine, day-to-day requirements.

I always chuckle when I fly and see the pad of 6x, 150-kW Tesla SuperChargers in our airport's long-term parking.
 
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Before buying my ID 4, I did my research and decided to upgrade to a 48 AMP charger. From everything I read a lot of people later on upgraded to 48 AMP. So I installed a 48 AMP charger and no regrets. I installed all the electrical and connections for under $100.00. Check out Tom Moloughney reviews. The reviews are very detail and honest. Hope this helps.
 
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