OpenEVSE - Open Source Charging Station

[borland]

Here's another idea for a graphic overlay of the clear cover enclosures.. There's a company selling an EVSE kit on eBay and the kit includes a clear cover enclosure and what looks like a placard mounted under the cover. The unit has colored LEDs and an LCD display, but no external buttons. Here's a couple photos from the listing..

On the silk screening idea was considering... I couldn't find any solvent-based ink at a reasonable price. Most of the inks are water based or for T-shirt applications.

garygid's idea to use a decal may be the best solution.. I see some vendors making adhesive backed vinyl decals from custom graphics files at a reasonable price.

 

[waidy]

Many thanks to the fearless OpenEVSE team, I am happy to report that my 75Amp OpenEVSEs work flawlessly at 240V. Darren got home from his ski trip an hour ago. Without unpacking, he wired the unit to a 14-50 outlet... And.. WaLa..

 

[chris1howell]

Many thanks to the fearless OpenEVSE team, I am happy to report that my 75Amp OpenEVSEs work flawlessly at 240V. Darren got home from his ski trip an hour ago. Without unpacking, he wired the unit to a 14-50 outlet... And.. WaLa..

Congratulations Waidy/Darren on a successful OpenEVSE build.

 

[TonyWilliams]

Many thanks to the fearless OpenEVSE team, I am happy to report that my 75Amp OpenEVSEs work flawlessly at 240V. Darren got home from his ski trip an hour ago. Without unpacking, he wired the unit to a 14-50 outlet... And.. WaLa..

Congratulations Waidy/Darren on a successful OpenEVSE build.

Woo Hoo !!!

 

[leafmealone]

Finished mine and loving it! Thanks Chris!

 

[waidy]

Finished mine and loving it! Thanks Chris!

Congrats! May I ask where do you buy your holster (the thing that holds the J1772 connector handle).

 

[waidy]

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[waidy]

Dear Chris, Darren said he will build the portable 30Amp OpenEVSE for me. I would like to confirm with you that the following items are additional items that I need to purchase for the OpenEVSE Plus (v2) Complete Package with EV Simulator:

* Get an OpenEVSE box from Aaron from Diversified Stage, Inc (Contact [email protected])
* Get one waterproof pushbutton (https://www.adafruit.com/products/481" onclick="window.open(this.href);return false
* Get one fuse block (http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=+BM6032PQ" onclick="window.open(this.href);return false
* Get one ground bar (http://www.homedepot.com/h_d1/N-5yc1v/R-100207842/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=Ground+Bar+Kit" onclick="window.open(this.href);return false
* Get a J1772 30Amp cable (http://store.leviton.com/b/5742800011" onclick="window.open(this.href);return false
* Get a a pair of 8 awg for two hots (black and red) and ____ awg green for ground (please fill in the blank)
* Get two rings, one for the J-cable (http://www.digikey.com/product-detail/en/CR8420-1000-G/582-1018-ND/1045174?cur=USD" onclick="window.open(this.href);return false and the other for the pair of 8 awg power cable (http://www.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&keywords=240-2119-ND&x=15&y=15&cur=USD" onclick="window.open(this.href);return false
* Get two cord connectors for the two big holes (http://www.polycase.com/cg-16" onclick="window.open(this.href);return false; or http://www.stayonline.com/detail.aspx?id=17209" onclick="window.open(this.href);return false
* Get a 14-50 plug (Oh no, now I need to get another wire for neutral. Do I connect the neutral to the ground bar?)

The reason why I want 14-50 plug instead of a 6-30 or 6-50 is because I have all sort of 14-50 pig tails which were built for my 2002 Rav4EV charger (including 14-50 to 6-30, and 14-50 to 6-50, etc. etc.)

New questions:
(1) Would the OpenEVSE Plus (v2) allows charging in either 120V and 240V (auto sensing?)
(2) Would the ready-made box from Diversified Stage big enough to host a 75Amp camper (out of curiosity) ?

 

[TonyWilliams]

Waidy,

Why not make this portable 40 amps, since that's both what RV parks can supply continuously from their NEMA 14-50 and that's what your Rav4 takes?

 

[waidy]

Waidy,

Why not make this portable 40 amps, since that's both what RV parks can supply continuously from their NEMA 14-50 and that's what your Rav4 takes?

I want to I want to.. That's why I listed Question #2. If Question #2 is positive, do I go back to the 75Amp part list, or is there a OpenEVSE Plus (v2) Complete Package with EV Simulator in 75Amp mode?

 

[91040]

A 75A contactor is in transit to Chris already. He will check if it fits in the new box. Based on the published dimensions of the contactor, it looks like it may not fit. Stay tuned.

The OpenEVSE will charge at 120 or 240V in the 30A version but, if I remember correctly, will only do 240V in the 75A version. It cannot drive the 75A contactor.

New questions:
(1) Would the OpenEVSE Plus (v2) allows charging in either 120V and 240V (auto sensing?)
(2) Would the ready-made box from Diversified Stage big enough to host a 75Amp camper (out of curiosity) ?

 

[mitch672]

The reason I used such a ginormous case for the 75A OpenEVSE was because the 75A contactor is very tall, over 4"+ I seem to recall. You also have the issue of the J-1772 cable, there are 30A and 75A Levitons, no 40A that I've seen, it's an oddball size.

 

[chris1howell]

Dear Chris, Darren said he will build the portable 30Amp OpenEVSE for me. I would like to confirm with you that the following items are additional items that I need to purchase for the OpenEVSE Plus (v2) Complete Package with EV Simulator:

* Get an OpenEVSE box from Aaron from Diversified Stage, Inc (Contact [email protected])
* Get one waterproof pushbutton (https://www.adafruit.com/products/481" onclick="window.open(this.href);return false
* Get one fuse block (http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=+BM6032PQ" onclick="window.open(this.href);return false
* Get one ground bar (http://www.homedepot.com/h_d1/N-5yc1v/R-100207842/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=Ground+Bar+Kit" onclick="window.open(this.href);return false
* Get a J1772 30Amp cable (http://store.leviton.com/b/5742800011" onclick="window.open(this.href);return false
* Get a a pair of 8 awg for two hots (black and red) and ____ awg green for ground (please fill in the blank)
* Get two rings, one for the J-cable (http://www.digikey.com/product-detail/en/CR8420-1000-G/582-1018-ND/1045174?cur=USD" onclick="window.open(this.href);return false and the other for the pair of 8 awg power cable (http://www.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&keywords=240-2119-ND&x=15&y=15&cur=USD" onclick="window.open(this.href);return false
* Get two cord connectors for the two big holes (http://www.polycase.com/cg-16" onclick="window.open(this.href);return false; or http://www.stayonline.com/detail.aspx?id=17209" onclick="window.open(this.href);return false
* Get a 14-50 plug (Oh no, now I need to get another wire for neutral. Do I connect the neutral to the ground bar?)

The reason why I want 14-50 plug instead of a 6-30 or 6-50 is because I have all sort of 14-50 pig tails which were built for my 2002 Rav4EV charger (including 14-50 to 6-30, and 14-50 to 6-50, etc. etc.)

New questions:
(1) Would the OpenEVSE Plus (v2) allows charging in either 120V and 240V (auto sensing?)
(2) Would the ready-made box from Diversified Stage big enough to host a 75Amp camper (out of curiosity) ?

Your list looks pretty good you will also need a relay/contactor and the CT for GFCI but I think you covered most of the big parts... I would not worry about the 8awg wires, when I build an EVSE I usualy take a little wire from the AC cord and a little from the J1772 to make all the high voltage connections. The wire in the cords are usualy higher quality and much more flexable than standard cable.

(1) Yes, the OpenEVSE Plus (v2) does auto sense Service Level when using a relay with a 12VDC coil, it will automaticly set a pilot value based on voltage. Example 30A pilot on L2 and 12A pilot on L1. Note this feature is not avaliable if other hardware in the EVSE has a fixed voltage requirement.

(2) It may fit but it will be really tight. A 75A contactor will have a fixed voltage requirement as the coil is 240VAC so (1) will no longer apply and the EVSE will be L2 only.

 

[GlennD]

Contactors typically draw about 15W so they need air flow. A small box will likely cause excessive temperatures. Many times the contactor is placed in air flow and never gets hot. The outside half of an air conditioner is like that.

 

[91040]

Is a bigger enclosure enough or is venting required?

Contactors typically draw about 15W so they need air flow. A small box will likely cause excessive temperatures. Many times the contactor is placed in air flow and never gets hot. The outside half of an air conditioner is like that.

 

[davewill]

... * Get a 14-50 plug (Oh no, now I need to get another wire for neutral. Do I connect the neutral to the ground bar?) ...

No, you don't need a neutral wire, and you definitely don't want to connect it to ground. Since the EVSE doesn't use a neutral, just leave that pin in the plug disconnected. Some plugs will allow you to leave the pin out completely, in which case it will plug into a 14-30R or 14-50R...but you'll want to be cautious about doing that. Plugging it into a 14-30R when the EVSE is set for 40a charging would cause the breaker to trip (if you're lucky).

If you end up using a molded plug and pigtail that includes the neutral wire, you can use a wire nut to cap that wire off inside the EVSE.

 

[GlennD]

Is a bigger enclosure enough or is venting required?

Contactors typically draw about 15W so they need air flow. A small box will likely cause excessive temperatures. Many times the contactor is placed in air flow and never gets hot. The outside half of an air conditioner is like that.

I purchased a 50A 220V coil contactor. When I received it, I put it in a 8 inch square cardboard box with the flaps closed. I then plugged it it to test the temp rise. After a half an hour it was too hot to touch.

I think whatever enclosure is used must have ventilation.

In my case I used a different contactor with 2 coils. It draws 10A at 12V until it pulls down and then only draws .1A to keep it pulled in.

 

[DanBaldwin]

In my case I used a different contactor with 2 coils. It draws 10A at 12V until it pulls down and then only draws .1A to keep it pulled in.

Interesting! Can you give us a supplier/mfg/part number for that contactor.

Dan

 

[Ingineer]

If you use a large 12v contactor, you'll need a LARGE 12v power supply too!

Chris: Consider adding optional opto-triac drive for HV contactor. In theory, this could be modulated under software control to allow using a 120V coil on either voltage. Could also feature an "economizer" that reduces power to the coil once the EVSE detects contact closure. (Hold power requirement is usually not nearly as high as pull in)

Experimentation would have to be done to select optimal values for PWM to prevent chattering/noise, so these should be programmable options. Not only would this reduce power consumption, but would DRASTICALLY reduce waste heat in the enclosure, allowing the use of hermetically-sealed small enclosures.

-Phil

 

[borland]

It's probably one of Mercury Relays products. They manufacture a 60A and 100A two pole relays that look like this..

http://www.mercuryrelays.com/100amp_relays.html

Beside containing toxic mercury content which is prohibited from sales in California, the 50ms release time probibits it from being used with GFIC.

For GFI, the total release time should be under 40ms ( see: http://en.wikipedia.org/wiki/Residual-current_device ). Those using two relays (12V coil and 240VAC coil), should consider combined release times under 40ms; so a solid state relay driving 240VAC coil contactor might be best.