120v to 240v EVSE Modification

[P-hack]

sooner or later someone is going to get fed up with the rediculous prices for a glorified power outlet and do something about it... (have you priced chademo connectors?!? its a f@#%@ing plug for literally thousands)

[rmay635703]

Originally Posted by P-hack

sooner or later someone is going to get fed up with the rediculous prices for a glorified power outlet and do something about it... (have you priced chademo connectors?!? its a f@#%@ing plug for literally thousands)

I never could understand why "maybe" $25 in cord + $10 in electronics costs $500. I understand its still a novelty and low production but come on?

Sort of like in the 1980s where you would pay $375 for a 10FT DEC video cable.

Whats old is new.

[P-hack]

anyone have a makerbot and can print me one of these in abs for a few dinero?

Chademo semi-compatible dummy plug - for testing by qualified persons only by erroneus - Thingiverse

[redpoint5]

I still have a few questions:

1. How do I tell what version of the Leaf EVSE I have? Apparently the 2011-2012 version is different than the 2013 unit. I want to make sure I follow the correct upgrade instructions for the unit I have.

2. Would 2 of these varistors work to protect the EVSE?

3. Could I use this dryer cable instead of building a connector using SJOOW? I'm guessing it's too thick to insert into the charger.

4. Why does the outlet need to be 4-wire? I mean, the ground and neutral wires are physically connected to the same grounding plate. How does separate return and ground wires add safety?

[P-hack]

1. my 2012 model is a 29690 3naoa
2. not an expert but those varistors look fine.

3. yes, but I would consider gutting it and putting it in a $10 pvc box from menards at that point (when you pick up your 8 gauge and 14-50 socket Another option is to drill a small hole for the neutral, 18 gauge is probably fine, and connect it to the cut transformer lead, spiral it around the existing cable, and hook it to 14-50 neutral, then silicone the hole, maybe throw a piece of flexable conduit around it while the plug is off.

4. the 4th wire is for neutral. This allows the controller/transformer to run off of 120v while passing 240v through to the vehicle. 240 to the center tap (neutral) = 120. It doesn't have to be large as it is in series with that little transformer (2w?)

[P-hack]

fyi, got tired of 120v charging and waiting on the cable so I cut the neutral to transformer lead, and drilled a small hole and fed a bit of 18 gauge into the case to connect the transformer to the 14-50 neutral, with a dab of silicone around the hole. wire just coiled around the cable. (edit, and I stabbed around the internal varistor goop and flexed it back and forth till it came out).

Also I didn't get to the updated power box, but had 2 legs of 120 on the existing box, (and was tired of waiting on the varistors) so I grabbed 2 $3 power strip surge protectors (15A), and unsoldered the cables and the varistors, and put the varistors in the plug, and put the cables in a female 14-50 for a quick 240v tap. So far so good. Will have to do better before it rains.

Note, I could use this adapter to find 240 via 120 outlets on different legs in the field. And a simple switch could make it work with 120 also (would be nice if it automatically detected 120, there's some room in the 14-50 female box, will see.).

[redpoint5]

I followed the Instructables procedure for converting my Leaf EVSE to output 240v, and now the Prius is charging in half the time, and with greater efficiency. The whole upgrade was $20 in parts for the varistors, SJOOW cable, ring terminals, and plug.

People are reporting that 120v charging is only about 70% efficient, and that 240v charging is about 85% efficient. I've found that to be true about 120v charging, and may never learn how efficient it is on 240v since I don't have a watt-meter that works on 240v.

The upgrade is extremely easy, yet was still time consuming because I had to modify the ring connectors I had to accept the 12 gauge wire from the SJOOW cable. The instructions weren't very clear as to what leg of the transformer to cut, and one of the photos even showed both wires cut. I encourage anyone with a Leaf charger to perform this mod, and I can help if there are any questions. I still don't see any info for upgrading the Prius EVSE to 240v. It's probably similarly easy, but I have no motivation to modify it now that I have my Leaf unit working.

I've also cleared some room in the garage and will try to park 2 vehicles in it. As much as I love the TSX, it's in serious danger of being replaced by an EV. I'm on the hunt!

Before Upgrade


After Upgrade

[P-hack]

The sjoow finally showed up, but I still am running my extra bit of 18 gauge for now, ties the old neutral transformer connection to the 14-50 neutral.

finally pulled the juicebox carcass after getting no help from emw on why the board they built quit. It is overkill for an early unmodded leaf anyway. Some pics of the new setup, nothing too fancy.

Menards had one of these 30a rv boxes for like $35, cant find it now, guess I got lucky there, but I cut it up to add a cheap watt meter and a 120v socket. The price jumps to like $110 for a stock 120 socket now :/
RV Power Outlet Panel Rainproof 30A Breaker Eaton Cutler Hammer Single 1 Phase | eBay

$25 quad breaker 20/30/30/20 Quad Breaker HOMT2020230CP | eBay (had to cut off part of the rv plastic to get it to sit flush).

$8 14-50R round socket to replace 3 pronger http://www.menards.com/main/electric...424-c-9526.htm

$3 20 amp 120 socket, tab removed, 1 on each leg, on seperate 20a breakers.

$12 watt tracker: 100A AC Digital LED Power Meter Monitor Voltage kWh Time Watt Voltmeter Ammeter | eBay
(monitors one leg current so one 120v socket can be watched also, or the other 120 used and not affect the kwh monitoring)
showing my last charge took 9.59 kwh. it is resetabble, otherwise cumulative.

Hope to have an excuse to upgrade to 50a breakers/feeder someday.