Can I use a step up transformer with my Prius plug in?

There is a communication standard integrated with the plug interface and specific signals that modulate rate or charge, max current, and connectivity. There is an open source charger that can be built for much less and lots of info on the SAE J1772 interface standard. google OpenEVSE for info

 

Expensive (if you have to buy new), heavy ( you will need a dolly to transport) and bulky. Besides it will have to be installed in a metal enclosure to cover all NEC standards

 

You wouldn't gain anything because max current from your 110volt outlet is 15amps and when you step up the voltage from 110volts to 220 volts the current is half. (7.5amps) Same thing as the Toyota Brick.

 

what is a step up transformer?

 

It basically takes a 120V input from the wall and outputs 240V (or whatever it's set to). The problem is that you are still limited to a total of 1800 watts from the 15A wall socket (15 amps * 120 Volts = 1800 watts). So you end only getting 7.5A at 240V (1800 watts / 240 Volts = 7.5 amps available). The 120V EVSE provided by Toyota only pulls a max of12A at 120V, or about 1440 watts. In reality, it's more like 10A at 120V, or about 1200 watts.

 

thanks dev!

 

We aims to please!

 

Rather than a step up transformer, use a quick220 to combine two 110V outlets into a 220V service. Here is a link to one you can purchase (Voltage Converter: 220 Volt from 110 Volt Outlets), or you can build one yourself (My Nissan Leaf Forum • View topic - Do It Yourself: 240v from two 120v sources)

This will supply 220/240V at 15Amps which is more than the Prius can draw.

I found that two of the outlets that supply my garage door openers work quite well. The outlets along the wall of my garage are on GFCIs.

Does the plug in EVSE (cord set) supplied with the PiP support 240V or would you need to get a European issue Toyota EVSE?

 

thanks for clarifying it for me.

 

Toyota went on the cheap, and the EVSE provided by Toyota is 120V only. It can be modified to support 240V (a service provided by one of engineering-type entrepreneurs on this forum).

 

GM went the same route with their 120V EVSE included with the Volt. It seems like Tesla is the only one shipping with a 120/240 cord set.

 

No, they had to comply with the National Electrical Code which was only recently revised. At the time, the NEC stated that a portable EVSE, such as the one included with the Prius Plug-in, can be rated up to 125V 15A/20A. Since the 120V outlets are mostly 15A which must be derated to 12A for a continous large current draw for an extended amount of time, the 120V/12A portable L1 EVSE is the best they could provide in compliance with the NEC and commonly available household outlets.

From: NEC 1999 Art. 625

If you are going to place blame, please place it where it is due.

 

Huh? So you are saying that Tesla is not compliant with the National Electrical Code? Didn't Tesla ship the Roadster before the PiP?

 

Perhaps "had to comply" was overstating it. The NEC is voluntary, so Toyota chose to comply, but Tesla chose not to comply.

 

Tesla shipped a portable 120V 15A capable unit. They also had a unit that could plug into NEMA L14-50 plugs (dryer plug) or other compatible plugs with the use of adapters. I'm no expert on that section of the NEC, but it looks like there is some wiggle room for Tesla's portable 240V EVSE.

That said, one reason that Toyota went with a standard 120V 15A unit is probably a mixture of cost and simplicity. *Everybody* has 120V 15A outlets typically available to them, especially at home. Shipping a unit that could do 240V adds cost and complexity and may only benefit a small number of owners. Not everybody has 240V outlets in their homes/garages. And charging at 240V is not as essential with the PiP as it is with the Leaf, Volt, Tesla, etc. Cutting the time from 3 hours to 1.5 is nice, but not essential.

 

SInce we are all guessing, here is my guess. Our PIP EVSE can be internally configured for ~120 or ~240 so the same device can be used in Europe and America. ust configure to the correct voltage, current and put on the correct plug.
And if you open one up to play with it, it will likely void the warranty on this expensive device.

 

The good folks at EVSE Upgrade - Products probably know better than any of us...

 

I doubt it's that simple. Ingineer (aka Phil) had to do a whole bunch of work to upgrade Nissan's (higher current capable) L1 EVSE to run at 240 volts. His service is at EVSE Upgrade - Products.

Using adapters to run the stock Nissan L1 120 volt EVSE at 208+ volts will definitely blow it. I'd think the same would happen to the Toyota unit.

BTW, for those in the Bay Area, I'd imagine that Phil himself will be present at Green Drive Expo - Bay Area. He was there last year and he had a table in the exhibits/vendor area. I've been trying to see who's going at SF Bay Area: Green Drive Expo 9/15/12 | PriusChat. The # of yay's, seems to be small this time.