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I'm hoping that someone that has some information on the 120V charging capabilities of the bolt. I realize that, in general, you wouldn't charge above 12A on 120V but I have been digging around trying to confirm if there is any way that the Bolt can be charged on 120V at say, 16 or 24 Amps? I found some level 2 chargers that are able to be limited to a customized amperage, and are auto switching between 120V and 240V. Has anyone ever successfully charged above 12A on 120V? This ties back to another post I made in a thread about charging in RV parks, but I'm really looking to focus on the technical aspect of this one. We have a lot more TT-30R (120V - 30A) available here (specifically thinking Ontario Provincial Parks) than say a 14-50R (240V - 50A).
 

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The car is limiting the charge current- the EVSE just supplies the electricity.

You could have a 120V EVSE with 1,000,000 amp capacity, the Bolt will only allow 12amps through it's charger circuit.

You'd have to hack the Bolt's charging system to allow more than 12amps at 120 volts.
 

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The EVSE has a protocol that allows it to signal to the vehicle what current it is possible to supply; the car is solely responsible for only drawing what the EVSE allows.
If your EVSE is telling the car that it's capable of 20 Amps, then the vehicle could take that amount of current. However, the Bolt appears to have it's own limits (8A or 12A for 120v supply), so it's probably going to clamp at 12A independent of what the charger claims. From a safety standpoint, that's not unreasonable. Code says that you shouldn't pull more than 80% of capacity, so for a standard 15A service 12A is all you're allowed. If you had #10 wiring (20A capable), you should be able to push 16A continuous.

Interesting question, however. If your EVSE claims it's capable of 20A at 120V, what does the Bolt do?
 

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It has no choice, it will max out at 12amps on 120v regardless of what the EVSE advertises.
120V charging is capped at 12amps period.
"It has no choice" really should be worded as "there is no configuration for the Bolt to allow more than 12 amps.".
J1772 allows up to 16A at 120v. If GM allowed that, and it caused a fire due to someone trying to pull 16A by "upgrading" a breaker, it'd be a lawsuit that they want to avoid. Setting a 12A upper limit is conservative.

Does anyone know what other EVs set for limits here?
 

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Tesla's will charge at most any amps @ 120v, 12, 16, 24 (for RV camp plug's that have 120v/30 amp plugs) - http://www.livingthervdream.com/120-volt-rv-electrical-system.html - Tesla's also support 240v @ most any AMP setting you like up to 72/80 AMP current draw (80 amp for older dual charger [optional] configuration, and 72 amps for the newer single charger [48 amps standard, 72 amp optional], and they of course work with the entire range of J-1772 allowed settings if you encounter a charger that supports one (for example I know of a 70 amp J-1772 charger in downtown San Luis Obispo).

I'm told this is a typical RV park setup…'

http://www.livingthervdream.com/120-volt-rv-electrical-system.html
 

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BTW the difference between 120 volts @ 12 amps and 120 volts @ 16 amps isn't that much in terms of actual benefit

1440 watts vs. 1920 watts (1.44 kW vs. 1.92 kW)

charging the Bolt @ 12 amps (from empty) = ~47 hours
charging the Bolt @ 16 amps (from empty) = ~35 hours

in either case I'd only charge long enough to get enough Juice to drive to a DCFC or 30 amp public charger.
 

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I'm just curious if anybody has actually used the 120v EVSE that comes with the Bolt and how much charge they get overnight?
Not a lot. Plugged overnight mooching power in a hotel parking garage, set to 8 amps. 120V * 8A = 960 watts. That's going to take 62.5 hours to charge the full 60kWh.
Or, putting it another way - say you get 4 miles per kWh. That means that you get 3.84 miles per hour of charging that way.

OK, let's do that for 12 amps. 1.440 kW charge. 5.76 miles per hour of charge.
That's why level 2 is so important. 240V * 32A = 7.680 kW, for 30.72 miles per hour of charge.

So my mooching wasn't worth it - ended up topping off using the DCFC across the street. Somehow my brain thought that overnight at 8A would make a real dent, but not really.
 

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I'm just curious if anybody has actually used the 120v EVSE that comes with the Bolt and how much charge they get overnight?
I actually use it as my sole charging source at home. My commute is around 50 mi (round trip) every week day. I plug the car in when I get home, usually total charging time is between 8-13 hours. I use 12A setting, so I get about 4 miles or so an hour. On most days, charging completes before I leave to commute the next day. If I have a week of lots of traffic free driving, I can catch up on weekends when I tend to drive less.

When I've done lots of driving in a short period of time, I'll usually catch up at a nearby public charger somewhere.
 
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