Using the Primes 120v Charger at 240 Volts, Cost $20 !!!

Mine was a SMPS to provide multiple DC power busses for a test and measurement instrument platform. 350W output, a pipsqueak compared to your motors, but by far the largest designed and manufactured by my facility.

An issue that later became significant was that these sorts of power supplies, with an input stage of just a full wave rectifier charging up large bulk capacitors, draw a very non-sinusoidal current waveform. They don't have much of a phase angle problem, instead they generate serious harmonics of the power frequency. Big transformers don't much like this. Three-phase delta-connected transformer banks really don't like the non-cancelling harmonic orders, starting with #3.

And then we discovered that the 120V volt circuit branches in our facility, mostly configured as separate phases of 3-phase with shared neutrals, were burning out in some areas that were heavily loaded with similarly-powered equipment. The facility was wired on an apparently common industrial assumption that those three separate phases sharing the neutrals would be partially cancelling out, so the neutral could use a smaller gauge. In reality, the large 3rd-order harmonic currents (180 Hz) were summing, enough to overload the neutral wires. The fix was to remove those downsized neutrals, and either to give them separate full sized neutrals, or a shared upsized one.

At about that time, the whole industry started demanding power factor correction. For this sort of device, that was accomplished by adding an additional stage, actively controlled, in front of the full wave rectifier. But my facility had ceased in-house power supplies (my very reliable design apparently was too expensive ), and I had already moved on to other design fields.

Plug-in car systems should use similar power factor correction.

 

Neither do variable frequency inverter drives. Most of our conveyors and lots of the machines were driven by variable speed AC drives. One day, out of the blue, they started tripping. Not here and there. Maybe a dozen at a time all at once. There was a big Whirlpool factory next door. They had installed a humongous welding machine that apparently threw out so much noise that it was getting into our power grid. They quickly took measures to fix that because I'm sure it was really wreaking havoc in their building. LOL!

Yikes!! I'm gathering that the hot wires were upsized for the harmonics and the neutrals were not? Last time I was at the radio station in Africa that I'm helping to build I noticed that the breaker panel in the unfinished shop had about a half dozen hot wires going out and only one neutral coming in. I asked about it and their electrician told me that the neutrals all met in a box above the ceiling and connected to the singe wire back to the breaker panel. I went and found my left eyeball that had rolled across the room and then informed him that he's expecting that one wire to carry the same current that all the black wires combined can carry. His response was that that was how they wired his last project and they hadn't had a fire. I'm probably going back there later this summer. It'll be interesting to see if they have fixed that or are still crossing streets blindfolded and somehow dodging the cars & trucks.

 

Welcome. What you have is a 14-50R, which is a receptacle. What you need to plug into it is a 14-50P which is a plug.


At the other end, you need a 5-15R or better yet a 5-20R to plug your EVSE into.


Use a short piece of something like 8-2 with ground SO cord to connect them to each other. When you've stripped the jacket from the ends of the cord, wrap black electrician's tape around the exposed white insulation to denote that it's hot. Then connect it to one of the two hot legs on each plug. Connect the black wire to the other hot leg on the 14-50P and to the remaining terminal on the 5-15 or 5-20. The neutral terminal on the 14-50 doesn't get a wire because you're not using a neutral. Ground goes to the ground pins. Like so:



THEN! Very important! Secure the adapter to the end of your EVSE to remind you that it goes with the EVSE and not with the receptacle. Otherwise someone who isn't paying attention could get a nasty surprise. Never leave the adapter hanging from the outlet.

Note: If you don't want to deal with working with #8 wire, you could replace the breaker with a 30 amp one and use #12 SO cord for the adapter wire. But for such a short piece of wire, I'd stay with #8 SO and not spend money on a breaker. Wire that's bigger than you need isn't a problem. Wire that's thinner than you need is a problem.

 

You could also just start with a cord like this instead which has the 14-50 plug with wire already attached. Then just cut off the receptacle and add the new one. Might be able to find one a bit longer.

 

Harmonics are already properly counted in the rms current ratings of the devices, so the hots are fine.

The fact that 3rd harmonics add together in this configuration, instead of phase cancelling out, was the main issue.

At least our neutrals weren't anywhere near that much smaller. IIRC, they were only a single step smaller. Though even that assumed that there would always be at least some limit to phase imbalance on these branches. While that might have been a reasonable assumption for the areas running heavy production equipment on three-phase 208V, it was way off the mark for the R&D and office areas, where all equipment was just 120V. There would have been many branches where one or two phases would be fully loaded, and the other two or one having little or nothing.

 

Wow, thanks for the very helpful information! I wish Toyota just made plug and play adapters for their EVSEs like some other manufacturers do!

 

Will something like this work?

 

Wow! I’ve never seen an adapter like that. I thought that would be illegal to sell in the US. Good find. Yes. Should work. Of course you could build your own for much less.

Edit: just thought of something. Maybe this adapter just uses one half of the 240 circuit and only provides 120 v on the output? Need to get more details.

 

Exactly.

Here:

 

Ah, I see. Thought it was too good to be true.

So that adapter gets a No.

 

A definite "NO." They buried the voltage it supplies in the fine print:

Apparently it's intended for someone without an available 120V outlet on their generator or other 240V power source. And it costs about 2-3 times what it would cost to just make one anyway.

 

Agreed. I couldn't find any indication it was producing only 120V. They really did burry it.
And it is way overpriced.

 

Yeah, unfortunately it was buried in the fine print. I guess technically it's not a good idea to sell something like that to an average consumer.

 

Did anyone noticed if thier toyota app reflects the correct charge status of the battery with the 240 plug adapter plug with oem charge cord? I made the adapter cord and the car charges at L2 speed as advertised as indicated on dash. But when I check on my app it still shows 2hrs10min to full charge.

Well after the car fully charged, the app now shows full charge. It's just during charging there is no update.

I guess I'll check again tomorrow when I charge

 

Well I tried charging again today and still no updated status on the app of battery level and charge time. I can live with that to be able charge with the DIY adapter.

 

I tried that app a while back and found it useless as a state of charge indicator. Just go by what the vehicle says.

 

Does it work correctly if you use it in a 120V outlet? I did not have a remote charge status function on my 2020 PP LE (nor on my 2017 PP Premium) and I did not have a 240v adapter, so I don't know the answer to your question. But I wonder if the remote charge level function of 2021 PP on the Toyota App works if the car is connected to a third-party L2 EVSE?

 

The level indication works with L2 charger that I got off Amazon, the Chargepoint charger at work and also works with oem cable in 120v mode.

I'm not too concerned just as long the car is able to charge in the 2 hours time and the charging indication on the car works which it dose. The app is only good for 2 year trail anyways.

 

Sound like there is some feedback from the EVSE for determining the charge current and estimating the charge level and the time remaining. The software in the APP might be confused when OEM L1 which should be working at 120v is now receiving 240v. Yeah, since that's an off-label use of the OEM L1 EVSE, Toyota or a dealer would not be able to help you. It's really not a mulfunctionig.

 

Yeah I'm just keep on DL about charging at 240