DC Charging Station

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Gune

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May 15, 2015, 1:26:24 AM5/15/15
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Dear all,

I am not a technical guy but I have one question I do not know whether this has answered before is there any possibility to have OpenDCEVSE. if not what are the technical difficulties.  

Thank you all OpenEVSE guys


Craig Kirkpatrick

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May 15, 2015, 1:45:01 AM5/15/15
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The brief answer is that for the J1772 standard the conversion of power from AC to DC occurs in the car. The EVSE is not a charger. It is a safety interlock. The major expense of conversion from AC to DC is left to the automobile companies. If the EVSE has to do that conversion then instead of a $249 EVSE kit you'd be looking at a $2,490 EVSE kit.

Prof. N K Gunawardena

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May 15, 2015, 2:23:05 AM5/15/15
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Dear Craig,

Thanks, It seems like possible with approx 10 times expense. That would be useful if some one think about installing commercial charging station where charging stations are not available like here in Sri Lanka no charging stations but EV's are around due to minimum import tax.


On Fri, May 15, 2015 at 11:15 AM, Craig Kirkpatrick <crai...@comcast.net> wrote:
The brief answer is that for the J1772 standard the conversion of power from AC to DC occurs in the car. The EVSE is not a charger. It is a safety interlock.  The major expense of conversion from AC to DC is left to the automobile companies. If the EVSE has to do that conversion then instead of a $249 EVSE kit you'd be looking at a $2,490 EVSE kit.

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Danny ter Haar

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May 15, 2015, 5:16:03 AM5/15/15
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Look here for such a setup

http://emotorwerks.com/products/online-store/category/listing/17-dc-charging-systems

Might be a good starting point.
As you probably know there are a couple of standards.
This ChadeMo cable is the cheapest I have seen yet:
http://www.ebay.com/itm/121630946864

I am also looking for such a project, if/when you find another alternative please share with us

Gune

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Jun 20, 2015, 12:27:10 PM6/20/15
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Dear Danny,

I read about this and made inquiry. According to them they have stopped selling kit now they sell only completely build charging stations only. but still you can find the build guide and part list firmware PCB design and etc. in their website.

My problem is it is hard and not worth try to shop for each and every component and order made single PCB for personal use. If someone like chris start some project based on this open source work definitely other also get  benefited.

This is part list


Main problem is making PCB

power board PCB


control driver PCB


charger build manual


all the files including firmware available in google drive



They recommend to read following book I found it in the web

Danny ter Haar

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Jun 21, 2015, 1:15:39 AM6/21/15
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On Saturday, June 20, 2015 at 9:27:10 AM UTC-7, Gune wrote:
My problem is it is hard and not worth try to shop for each and every component and order made single PCB for personal use. If someone like chris start some project based on this open source work definitely other also get  benefited.

In _my_ terms an (open)evse is nothing more than a super secure extension cord.
There is basically only security checking and notification of how much current can be drawn from "the wall".

Chademo in simple (technical) words:
It is a programmable power supply between 50-500 volt with (again) security measures.
Constant current to a certain limit of the battery voltage and then switches to constant voltage to finish the charge (not even at 100% battery charge limit)

That means that you need so many components, interpreting temperature settings from the batteries xx amount per second and a lot more.
The change of building something like that is a _lot_ more challenging than an EVSE.
Working with voltages that are absolutely _deadly_ (DC is way more dangerous than AC imho)
I see myself travelling a lot between California and Oregon the next year. There is not a path that has quick chargers between those 2 states. But there are places where truck can hook up the cooling equipment of their trailers to  "shorepower.com" like seen here: http://www.shorepower.com/etru/

The connector says: 480 volt, 30 amps, 3 phase
So in theory you could draw 480x3x24 amps (80% of 30) = 34 kWatt
It would be awesome to make a portable ChadeMo charger to plug those in and charge your EV at those rates. Suddenly the trip between Ca en Or would be a lot faster!

I will continue looking at all the information you provided to see if fabricating something like that is possible. The problem here (in the USA) is the liability of such products.
I would _never_ sell a unit to anyone. Totally afraid someone would sue me 
We can keep dreaming however ;-)

Gune

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Jun 21, 2015, 3:14:20 AM6/21/15
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Thank you for your post. If you think of selling do not sell fully built one just sell the kit then they have the responsibility to test and check for suitability to use for day to day work.

I found another forum dealing with DC chargers

They are working on a 240v AC powered device, but the project is broken up into three pieces, a DC power supply, a DC-to-DC converter to make the correct voltage as needed, and a CHAdeMO interface module. In particular, they've been working on their own CHAdeMO plugs.

 Please checkout 

Marry Jeyn

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Mar 3, 2025, 3:12:56 PMMar 3
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Hello everyone! We are planning a big event and would like to install a charging station for guests. Is it possible to rent such a station, and how convenient is it?

Dasa

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Mar 3, 2025, 5:04:51 PMMar 3
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Yes, renting charging stations is a really cool solution for events! I was at a conference where they installed several of these points, and it saved my phone. Some companies, such as mobile phone charging station, offer rental of charging stations for any period of time. They install stations with different connectors, wireless charging and closed cells, so that guests can safely leave their phone and not worry about it getting lost. If you are organizing an event, definitely think about this - it is really useful!
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