Adjusting Amp Draw

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Aaron

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Is there a way to adjust the amp draw on our level 1 chargers? I think Teslas can do this...I was just curious if we could as well.
Why do I ask you ask?
Currently I have a 20 amp GCFI outlet in my garage. I have a 5 cf freezer that draws 5 amps and I want to hook up my clarity to the same outlet until I get something more permanent.
5 amps plus 11 amps is 16 amps which puts me at the 80% safe zone for continuous load until I come up with something else.
5 amps plus 12 amps puts me at 17 amps which won't blow my breaker but will put me over the 80%.
Thoughts?
Thanks!
 
The Clarity does not have the option to limit the draw under what the charger is rated for. The charger will send the car information when you plug it in to set the max charge current and the car will not exceed that. I would also add that the freezer would not be on much more then a few minutes every hour or so, I do not think you would have an issues unless the freezer is running for the whole time the car is charging.
 
It will draw less current when the car is nearing the end of charge to balance the batteries. When charging with the included charger I would see 12.2a with a kill-a-watt. I do not know of any level 1 charger that goes below 12a
 
The JuiceBox Pro 40 level 2 charge station has the ability to limit the current. I'm sure other charge stations do as well.
 
Aaron said:
Is there a way to adjust the amp draw on our level 1 chargers? I think Teslas can do this...I was just curious if we could as well.
Why do I ask you ask?
Currently I have a 20 amp GCFI outlet in my garage. I have a 5 cf freezer that draws 5 amps and I want to hook up my clarity to the same outlet until I get something more permanent.
5 amps plus 11 amps is 16 amps which puts me at the 80% safe zone for continuous load until I come up with something else.
5 amps plus 12 amps puts me at 17 amps which won't blow my breaker but will put me over the 80%.
Thoughts?
Thanks!
Click to expand...
If your freezer load of 5 amps is the start up load you're probably ok. If your freezer load of 5 amps is running load it might trip your 20 amp breaker (while you're charging). Start up load is always more (sometimes much more) than running load.

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Richard_arch74 said:
If your freezer load of 5 amps is the start up load you're probably ok. If your freezer load of 5 amps is running load it might trip your 20 amp breaker (while you're charging). Start up load is always more (sometimes much more) than running load.

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Click to expand...
Found this on start up load vs running load.
Screenshot_20181116-151126_Google.webp


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Richard_arch74 said:
Found this on start up load vs running load.View attachment 2917
Click to expand...

Most sources say starting current on a freezer can be 10x running current. I think that's based on ancient compressors and bad capacitors, though. I have real-time graphs connected to smart meters at two locations, one of which has a big 15 year old freezer and 1 year old bottom-freezer refrigerator, and the other a side-by-side freezer/refrigerator. None of them cause any spike at all on the graph when the cooling comes on. My fridge/freezer says 6.5 A on the label. It's plugged into a dedicated 5-20 socket with a 20A breaker. If it spiked even a little over 3x, it would be tripping the breaker every time it came on.
 
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Aaron said:
This is excellent!
One of my concerns is that slowly over time I might burn out the wires without tripping the breakers.....
Am I overconcerned?
Click to expand...
When dealing with electrical concerns, it is prudent to be cautious. Depends on a lot of things: how do you know that the freezer is the only thing on the circuit (like lights, receptacles, or another appliance)? Do you know for sure that you, indeed, have 12-2 w/gr. wire along the entire circuit with 20A rated receptacles?
Attached is a screenshot of GE's recommendations (note they say 2x extra load on start up (10A), that's why they suggest freezer on dedicated circuit). Yeah, probably conservative but . . . .
If the freezer is the only thing on the garage circuit it will probably work. Just depends if you want to be comfortable with probable.
Screenshot_20181116-161459_Chrome.webp


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Richard_arch74 said:
When dealing with electrical concerns, it is prudent to be cautious. Depends on a lot of things: how do you know that the freezer is the only thing on the circuit (like lights, receptacles, or another appliance)? Do you know for sure that you, indeed, have 12-2 w/gr. wire along the entire circuit with 20A rated receptacles?
Attached is a screenshot of GE's recommendations (note they say 2x extra load on start up (10A), that's why they suggest freezer on dedicated circuit). Yeah, probably conservative but . . . .
If the freezer is the only thing on the garage circuit it will probably work. Just depends if you want to be comfortable with probable.View attachment 2918

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Click to expand...

You make a very good point. I'm not very comfortable with probable when talking about burning down my house.
:(
 
I'm not sure how convenient this is for you but you could install a dedicated circuit for the car charger and it could be 20amp as well. The advantage of this is that you could then get yourself a 16amp level 1 charger which would be about 30% faster than the one you have now. If your subpanel is already in the garage this could be a very quick and cheap fix.
 
watch for a juiceplug to show up on ebay this will allow you to track your consumption and set max current.

If you are dropping a new circuit and it needs to be as cheap as possible do it for 220v @ 20a with a NEMA 6-20p and look into getting a 16a level 2 evse.

This will use the same 12 awg as an 120v circuit.
 
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So I purchased a "Kill a watt" device and my freezer pulls a little less than half an amp and the clarity was running at about 10.5 amps. This was charging with about 40% of the battery. I would say in this scenario.....I'm good. Granted....it takes forever but it will work until I find someone to install the 220 (240?) outlet in our garage.
Thanks everyone!
 
Aaron said:
So I purchased a "Kill a watt" device and my freezer pulls a little less than half an amp and the clarity was running at about 10.5 amps. This was charging with about 40% of the battery. I would say in this scenario.....I'm good. Granted....it takes forever but it will work until I find someone to install the 220 (240?) outlet in our garage.
Thanks everyone!
Click to expand...
Just curious, did you happen to catch the display when the appliance started up? Was it 1 amp of draw (2× running draw)?

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