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Discussion Starter #1 (Edited)
If / when I get an Ampera e, I plan on buying a portable EVSE that can be set at various max charge rates. One particular contraption I have in mind can be limited at 6, 8, 10, 13, 16, 20, 24, 28 and 32 Amps.

Do we have info on how much power (watts or amps) the Bolt actually draws from a 240 volt socket, with a charge station set to these levels? In another post, I read it maxes out at 7.7 kW. But how about the other settings?

I am especially curious what the Bolt does on charge station limited to 16 or 20 amps.
For reference, my Outlander PHEV does only 3300 watts (approx. 14 amp) when hooked up to a 16 amp charge station.

Thanks.
 

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If / when I get an Ampera e, I plan on buying a portable EVSE that can be set at various max charge rates. One particular contraption I have in mind can be limited at 6, 8, 10, 13, 16, 20, 24, 28 and 32 Amps.

Do we have info on how much power (watts or amps) the Bolt actually draws from a 240 volt socket, with a charge station set to these levels?
Watts = Volts x Amps

For example, 240 Volts at 20 amps = 4800 Watts (4.8KW)
 

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Discussion Starter #3
Saen,

Thanks for that. You just put a big smile on my face ;)

I am 'more or less' familiair with the theory. But what I meant to ask is this: when hooked up to a charge station limited to (for example) 20 amp, how much amps (or watts) will the car draw in reality? Indeed the full 20 A (4800 w)? Or maybe just 19 A (4560 w)? Some EV's are known to keep a little safety margin towards the limit set by the charge station. The reason for asking is that I probably will target using 20 Amp setting on a socket secured with a 20 amps fuse. If the car takes the full 20 amps, losses in the line between the fuse and the car may cause the fuse to trip...
 

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I'm in the same boat, or will be when my Bolt arrives. In my garage, the question is will it work at 30a on a 30a breaker. Worst case I'll set the EVSE down to 24a, which should be safe.

The best approach is to try it. If the breaker doesn't trip, go for it. If you push it with a bigger breaker, you will probably be risking overheating the wire.

BTW, with two different EVSEs with displays and my Spark EV, both have consistently shown around 14.5a when charging while set to 16a on the EVSE.
 

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I'm in the same boat, or will be when my Bolt arrives. In my garage, the question is will it work at 30a on a 30a breaker. Worst case I'll set the EVSE down to 24a, which should be safe.

The best approach is to try it. If the breaker doesn't trip, go for it. If you push it with a bigger breaker, you will probably be risking overheating the wire.

BTW, with two different EVSEs with displays and my Spark EV, both have consistently shown around 14.5a when charging while set to 16a on the EVSE.
I read somewhere if you have a 30 amp for the dryer you can use it but need to change the setting to 24amp. People talk about burning the house down. Not sure it can happen but don't want to find out. I've been using the 30 dryer set to 24 till I get a panel change out and a 50 amp circuit to the charger.
 

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The EVSE tells the car what it can supply, the car decides what to pull (in terms of amps). If you set the EVSE to (say) 24 amps, then it will tell the car it can supply 24 amps, and (I would expect that) the car will pull a MAX of 24 amps (24A x 220V = 5.28 kW ; 32A x 220 = 7.04). Not all of that energy goes into the battery - there is some current loss.

In terms of circuit breakers and safety, the guideline in the U.S. has been for a very long time that a continuous pull on an electrical line should not go past 80% of the max rating. So on a line with a MAX rating (i.e., a circuit breaker) of 30A, I myself personally would not plug anything that draws over 24A for an extended period (more than 10 mins).

Lastly, I can't tell you what your EVSE and car combo do when you set the EVSE to (say) 30A. Are you setting the EVSE's max draw to 30A (and the car will be pulling a continuous 30A)? The only way to know is to try it. My car when turned on (Chevy Spark EV) will show how much energy is being 'regenerated' (pushed back into battery). So if I am at a DCFC and turn on the car, I see the kW being pushed in. You might be able to do the same on the Bolt. Or maybe there are other ways to see exactly how much energy is being taken in on the Bolt.

I hope this helps.
 

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I've been using the 30 dryer set to 24 till I get a panel change out and a 50 amp circuit to the charger.
You will need to upgrade the wiring to 8-ga. for a 50a circuit. 30a circuits are usually wired with 10ga.
And SparkE is correct - running the circuit at max. capacity is risky behavior, even if the breaker doesn't trip. So I guess I'll be charging at 24a, extending charge times by 25%. No problem.
 

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Where is the 32 amp setting mentioned on page 231 '9.5 hours to charge the vehicle with the 32 amp setting'. Page 126 'Charge Current Limit Selection' only mentions 8 and 12 amp settings for 110 volt source.
Page 130 'Location Based Charging' (like your home) tells how to establish a location but no mention of Current Limits.

I have a Juice Box rated at 40 amps plugged into a 50 amp 240volt circuit and want to charge at the maximum allowable rate - but where is the option to set this ?
 

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Where is the 32 amp setting mentioned on page 231 '9.5 hours to charge the vehicle with the 32 amp setting'. Page 126 'Charge Current Limit Selection' only mentions 8 and 12 amp settings for 110 volt source.
Page 130 'Location Based Charging' (like your home) tells how to establish a location but no mention of Current Limits.

I have a Juice Box rated at 40 amps plugged into a 50 amp 240volt circuit and want to charge at the maximum allowable rate - but where is the option to set this ?
in the Juicebox menu just set the current to 80% of whatever your circuit is. mine is on a 40 amp circuit so I have it set to 33.
The bolt charger is limited to 32 amps at 240 volts at level 2
 

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You will need to upgrade the wiring to 8-ga. for a 50a circuit. 30a circuits are usually wired with 10ga.
And SparkE is correct - running the circuit at max. capacity is risky behavior, even if the breaker doesn't trip. So I guess I'll be charging at 24a, extending charge times by 25%. No problem.
I'm having the electrician run a new line for the 50 amp breaker and not using the dryer one.
 

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Discussion Starter #11
The EVSE tells the car what it can supply, the car decides what to pull (in terms of amps). If you set the EVSE to (say) 24 amps, then it will tell the car it can supply 24 amps, and (I would expect that) the car will pull a MAX of 24 amps (24A x 220V = 5.28 kW ; 32A x 220 = 7.04). Not all of that energy goes into the battery - there is some current loss.
All that is completely understood. I know the car will pull max 24 amps in that situation. That is the whole point of the L2 protocol. But I am interested to find out how much it will actually pull.

Not all of that energy goes into the battery - there is some current loss.
For sure. It gets worse, I guess: if the car itself pulls the full 24 amps on a 24 amps setting, even more amps will go over the line, as there are losses upstream also (although I am not sure it is really current that gets lost, as current should be the same all over the line up to the OBC).

In terms of circuit breakers and safety, the guideline in the U.S. has been for a very long time that a continuous pull on an electrical line should not go past 80% of the max rating. So on a line with a MAX rating (i.e., a circuit breaker) of 30A, I myself personally would not plug anything that draws over 24A for an extended period (more than 10 mins).
Fortunately, I am not in the U.S. (yes, that was a joke ;)).

Lastly, I can't tell you what your EVSE and car combo do when you set the EVSE to (say) 30A. Are you setting the EVSE's max draw to 30A (and the car will be pulling a continuous 30A)? The only way to know is to try it. My car when turned on (Chevy Spark EV) will show how much energy is being 'regenerated' (pushed back into battery). So if I am at a DCFC and turn on the car, I see the kW being pushed in. You might be able to do the same on the Bolt. Or maybe there are other ways to see exactly how much energy is being taken in on the Bolt.

I hope this helps.
Neither me, nor EldRick does have a Bolt (or Ampera e) yet to try with. Nor do I have the proper EVSE (don't know about EldRick). That is the whole point of asking this question here. But it is not about my EVSE, IMHO. It is about how a Bolt behave when any EVSE is set to 20, 24, 30 ... amps. As the protocol is the same for all EVSEs. So, I was hoping somebody else would be willing to try it. Or already knows ...

The reason for wanting to know upfront is that I would like to know whether I will be able to charge with 20 amps or only 16 amps with my current setup, as 20 amps allow me to add 25% more kms or miles per night. Currently my house is connected to the grid with 3 x 25 amps. Upgrading my connection to 3 x 35 amps will cost me about 1000 USD yearly, so I am a bit reluctant to do so ....
 

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You should charge at 80% of the max rating of the circuit you plug into for safety's sake. If it's a 30A circuit, you set the EVSE to 24A, and the car will pull a maximum of 5.76 kW at 240V. Whether or not the battery gets the full 5.76 kW is another matter. The car might might pull less because the battery is too hot/cold, the SOC is above a certain threshold, or due to internal charger losses. But that 5.76 kW is the max that the car will ever pull from the wall with the EVSE set to 24A on a 30A circuit.
 

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Discussion Starter #13
You should charge at 80% of the max rating of the circuit you plug into for safety's sake. If it's a 30A circuit, you set the EVSE to 24A, and ...
I appreciate your concern and advice, but that was not my question. FYI: Of course the max rating of the circuit is a concern, but I was only talking about the fuse in the circuit. If the circuit is properly dimensioned for whatever setting I choose but the fuse is not, the worse that can happen is that the fuse will trip.

But that 5.76 kW is the max that the car will ever pull from the wall with the EVSE set to 24A on a 30A circuit.
I know it is the max it is allowed to pull (240 v * 24 a), but have you seen it actually pull that much? Or will it maybe only pull for example 5.52 watt (240 v * 23 a)? Because that is the kind of info I am after. But more for 20 amps than for 24 amps ;)
 

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I appreciate your concern and advice, but that was not my question. FYI: Of course the max rating of the circuit is a concern, but I was only talking about the fuse in the circuit. If the circuit is properly dimensioned for whatever setting I choose but the fuse is not, the worse that can happen is that the fuse will trip.

I know it is the max it is allowed to pull (240 v * 24 a), but have you seen it actually pull that much? Or will it maybe only pull for example 5.52 watt (240 v * 23 a)? Because that is the kind of info I am after. But more for 20 amps than for 24 amps ;)
I have a 30A hardwired unit, so I can't answer that specific question (20A or 24A). I will be able to the question of max draw on a 30A EVSE later today/tonight after I've done a 100+ mile trip.

Depending upon the circuit breaker/fuse you have for the circuit you use, it may not trip correctly if you actually continously draw 20A on a 20A circuit for an extended period of time. Instead, the wires will just slowly heat up, potentially melting/deforming, which could cause a problem like a fire.
 

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Discussion Starter #15
I have a 30A hardwired unit, so I can't answer that specific question (20A or 24A). I will be able to the question of max draw on a 30A EVSE later today/tonight after I've done a 100+ mile trip.
Thanks. I would appreciate that. Have a safe trip.
 

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Confirming that it works as expected, I set my EVSE to 24a max (up from 16a) and my Spark still drew the same 14.5a while pre-warming.
I'd imagine the Bolt will work the same way, and even though the electrician told me to "give it a try" using 30a on 10ga wire, I'll stick to 24a for safety. I'm pretty sure that my pattern of plugging in overnight at 24a (18 to 20 miles/hour) will be more than enough to keep the battery charged.
 

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Confirming that it works as expected, I set my EVSE to 24a max (up from 16a) and my Spark still drew the same 14.5a while pre-warming.
I'd imagine the Bolt will work the same way, and even though the electrician told me to "give it a try" using 30a on 10ga wire, I'll stick to 24a for safety. I'm pretty sure that my pattern of plugging in overnight at 24a (18 to 20 miles/hour) will be more than enough to keep the battery charged.
So answer me this.... my charger is the Clipper Creek 40(32amp 240v) and it's on a 40 amp breaker in fuse box. But the Bolt will only draw 8amps or 12amps if you set it to 12amps. The car will only charge at 12 amps right??
 

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Has anyone put a scope on the house power when a Bolt or other EV is charging?
As a hi-fi fanatic, I've been wondering how much voltage sag and RF noise the charger in a Bolt puts on the power lines. If an air conditioner can cause visible voltage sag when it comes online, I wonder what happens when the Bolt AC-DC convertor fires up and draws 7kW?
Yet another argument for charging at night when it can't interfere with my music...
 
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