Is 24A 120V charging possible?

Obviously not with the standard L1 EVSE.

There might be some niche uses for 120V only charging solutions. The 6kW OBC can handle 27.5A 240V, but I've only seen instances of 120V charging up to 16A (EVSE Upgrade). Is this just because 240V is only nominally more expensive, or is there some other limitation?

I'm mostly curious because I have a L5-30 outlet in my garage. Unfortunately, I can't use something like Quick220, because all the circuits are the same phasing. (Split phase is silly like that). The L5 looks added after the house, and was probably used for something like an air compressor. My dryer is gas, so it also runs on 120V.

Probably a dedicated outlet. If so you could repurpose the configuration to 240 volts by moving the neutral and hot to a double breaker in the main panel along with changing the connector to L6-30. You would need to mark/indicate the white wire is hot with red tape at each end. If the pull is easy I would replace the wire. Then EVSEUpgrade is plug and play.

smkettner said:

Probably a dedicated outlet. If so you could repurpose the configuration to 240 volts by moving the neutral and hot to a double breaker in the main panel along with changing the connector to L6-30. You would need to mark/indicate the white wire is hot with red tape at each end. If the pull is easy I would replace the wire. Then EVSEUpgrade is plug and play.

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That's not what I asked.
It's also not trivial to trace the neutral back to the source. Since the neutral line is grounded, it's not connected to a breaker.

IIRC the 2011/2012 LEAF only charged at at a maximum of 12A even if the pilot advertised more amps at 120V. Don't know if this was changed for newer LEAFs (a quick search suggests that they work at higher amperage levels). Clearly some chargers are making assumptions in limiting the charge current when the input voltage is 120V though I'm not aware of any inherent reason they need to.

If you know someone with an OpenEVSE or a JuiceBox premium you can probably conduct the experiment pretty easily.

Finding the neutral might is potentially doable sanely. As someone else suggested it is probably a dedicated circuit. The number of wires on the neutral bar of the appropriate wire size is probably small. You can try some ideas here on how figure which is the right circuit:

https://answers.yahoo.com/question/index?qid=20091231184054AAwhV0h" onclick="window.open(this.href);return false;
http://forums.mikeholt.com/showthread.php?t=135678" onclick="window.open(this.href);return false;

If I was trying to figure out I would turn off all the breakers except the L5-30, put a load on the L5-30 and use a non-contact probe to test neutrals.

An electrician should also be able to upgrade the L5-30 to L6-30.

arnold

OK you could also get a transformer to step up voltage but I don't recommend it.
Will the on board charger accept 24 amps 120 volts.... NO. I don't think there is an EVSE that will accommodate 24a & 120v.

If the circuit was an add-on I bet it is easier than you think to find.
Best to call an electrician at this point.

mctom987 said:

There might be some niche uses for 120V only charging solutions. The 6kW OBC can handle 27.5A 240V, but I've only seen instances of 120V charging up to 16A (EVSE Upgrade). Is this just because 240V is only nominally more expensive, or is there some other limitation?

I'm mostly curious because I have a L5-30 outlet in my garage. Unfortunately, I can't use something like Quick220, because all the circuits are the same phasing. (Split phase is silly like that). The L5 looks added after the house, and was probably used for something like an air compressor. My dryer is gas, so it also runs on 120V.

Click to expand...

It sounds like you may have only a single phase in your breaker box if everything is on the same phase.

The Clipper Creek ACS-25 claims 20 amps output at 120 volts. It might be the best answer for your 30 amp 120 volt circuit.

I have read that the newer Leaf will draw 16 amps at 120 volts if offered, I don't know if they will go more. I also don't know if that varies between te 3.3 and 6.6 kW chargers.

I have tested my 2013 leaf at 18A. This is the max the current table went. Since I have 240V available I did not test further.

The default 12A is the max for a stock 15A circuit. 16A is the max for a 20A circuit. 16A is quite doable with a dedicated 20A circuit. Anything higher would require special wiring and connectors. If you have to run the wire why not run an extra wire for 240V?

I understand that Tesla based cars can charge at 20A on 120V. I read on the RAV4 EV forum that that low current confuses the charger at 240V.

The charger in the car has to bump the supply voltage all the way up to 400 volts dc for the battery. 120 volts ac can make only 170 vdc so clearly there has to be an additional transformer in there for the lower voltage. That would limit the maximum current for the charger to a lower value for 120 than the max for 240.

johnrhansen said:

The charger in the car has to bump the supply voltage all the way up to 400 volts dc for the battery. 120 volts ac can make only 170 vdc so clearly there has to be an additional transformer in there for the lower voltage. That would limit the maximum current for the charger to a lower value for 120 than the max for 240.

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Considering most houses don't have 120V outlets >20A, it would make no sense for Nissan to invest in a transformer nobody would use. This actually makes a lot of sense, and probably explains why all the EVSEs are 240V.

Thanks for the explanation.

arnolddeleon said:

If you know someone with an OpenEVSE or a JuiceBox premium you can probably conduct the experiment pretty easily.

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According to the JB instruction manual, the current limiter can be set anywhere from 0 to 30A at 120V. The default setting at 120V is 15A. However, I never use mine at 120V since I have it plugged in to a 240V outlet.

GlennD said:

I understand that Tesla based cars can charge at 20A on 120V.

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Apparently, some newer Model S have been able to get 24A on 120V. To be honest, I would probably dial down to 20A in most cases anyway. I would not trust a camp site TT-30 to take the full rated load for continuous current. The one time I used an RV park's 14-50, the breaker jumped at 40A and I had to set a 36A limit.

Berlino said:

GlennD said:

I understand that Tesla based cars can charge at 20A on 120V.

Click to expand...

Apparently, some newer Model S have been able to get 24A on 120V. To be honest, I would probably dial down to 20A in most cases anyway. I would not trust a camp site TT-30 to take the full rated load for continuous current. The one time I used an RV park's 14-50, the breaker jumped at 40A and I had to set a 36A limit.

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I've charged with my full sized evse multiple times at different parks using both the 14-50 and two tt-30s. 27.5 amps, the full 6.6 kw the car can support. Also with dryer plugs and shop 6-50 outlets. I Haven't had a problem yet. What I do is monitor everything for the first 15 minutes to make sure nothing is getting too hot. There have been times I went to a different plug because that one felt too loose. Very common in rv parks. The plan is if anything is getting too hot or breakers blow, I take out the evse upgrade I use as a backup, and charge at 20 amps, and just wait longer. I err on the side of caution however if I am plugging into a 30 amp outlet attached to a structure. I have no idea how it is wired. Don't want to burn my buddies house down.

mctom987 said:

Obviously not with the standard L1 EVSE.

There might be some niche uses for 120V only charging solutions. The 6kW OBC can handle 27.5A 240V, but I've only seen instances of 120V charging up to 16A (EVSE Upgrade). Is this just because 240V is only nominally more expensive, or is there some other limitation?

I'm mostly curious because I have a L5-30 outlet in my garage. Unfortunately, I can't use something like Quick220, because all the circuits are the same phasing. (Split phase is silly like that). The L5 looks added after the house, and was probably used for something like an air compressor. My dryer is gas, so it also runs on 120V.

Click to expand...

There is no point to residential high current 120V because the outlets are so rare. If you are adding an new outlet you would go 240V. In addition you could easily convert a L5-30 to a 30A 240V outlet and now have 24A 240v charging which is 2X the power. Even people with a dedicated 20A 120V outlet can convert it to 240V and have 2X the power. If you have three wires of 10G on 120V it is better used for 240V.

I like the nema 6-20. Yes, a 30 or a 50 is better. But the 20 will fit into a regular box easily and if it's a dedicated outlet easily converted to 240. J6st make sure it is indeed dedicated. I have heard horror stories. Most of the mechanics i know have one in their shop for the air compressor.

So, apparently 30A 120V is indeed possible.
youtube.com/watch?v=3NWvIpRAjqY

wow that's a good deal. Might also help for charging at RV parks when all they have is a tt-30 outlet.

I think that's a large reason as why he was testing it.

From what I can tell, he's using a JuiceBox with the 14-50 plug, and connecting the L1 and neutral instead of L1 and L2. This basically gives a max rating of 120V 50A.

240V is certainly better than 120V, but sometimes 240V isn't an option, like those old TT-30 plugs. Significant improvement over the stock 12A 120V setting.