OpenEVSE - Open Source Charging Station

[garygid]

Thanks, VERY helpful.

Then, in making the Arduino Uno version:
1. The Arduino and EVSE Shield replace the OpenEVSE board?
2. Does one lose some of the features of the OpenEVSE board?
3. Does one also need to add a 9v or 5v Power Supply for the Arduino?

I will try and find the Arduino-EVSE thread.

Thanks.

 

[chris1howell]

The Arduino shield...

- quite a bit larger
- all the pins map to the same places as Open EVSE
- all the features are the same (GFCI - diode check - etc)
- runs the same software
- DIP and through hole components make hardware hacking easier
- all pins including pins in use are accessible
- will be available in a kit
- powered by standard 12V supply (when relay is required) or over USB (all features except relay)
-better suited to hardware/software development

Open EVSE
-prebuilt boards are very small
- powered by standard 12V supply
- most unused pins are accessible
- better suited for EVSE

 

[mitch672]

Thanks, VERY helpful.

Then, in making the Arduino Uno version:
1. The Arduino and EVSE Shield replace the OpenEVSE board?
2. Does one lose some of the features of the OpenEVSE board?
3. Does one also need to add a 9v or 5v Power Supply for the Arduino?

I will try and find the Arduino-EVSE thread.

Thanks.

1. yes
2. no
3. yes, the Arduino would need to be powered, has a DC coaxial connector for that (or can use USB power when plugged into your PC for programming)

Chris has the Ardiuno Shield prototype detailed on the contest site: http://www.instructables.com/id/Arduino-EV-J1772-Charging-Station/" onclick="window.open(this.href);return false;

Chris elaborated on the differences above as well. If you are going to be makiing frequent changes to the code or adding features, the Arduino shield version can stay on your "bench" while the OpenEVSE board stays working as an actual EVSE (so you have a "development platform")

There is no difference other than the size of the platforms hardware, if you are going to be adding additional hardware, such as an ethernet interface, GPS, etc, there are standard "Arduino Shields" you can buy and stack up, so that's a plus for the Arduino shield version.

 

[richard]

Chris,

In the "photo of programming setup" image you have uploaded to OpenEVSE, you seem to have two programming cables attached to the board at once. Why is this?

Also, can you post a link to the exact Adafruit display and "backpack" you're playing with.

Trying to keep up with you

Thanks for this project,
Richard

 

[garygid]

Edited to make it correct:

It looks like the +/- 12v for the Control Pilot gets generated from 5v on the EVSE-Shield, so one needs to supply only the voltage to operate the relay.

If one supplies only +12 to the OpenEVSE, that powers the Relays and is used to provide 5v for the circuitry, which generates the +/-12v for the Control Pilot.

 

[mitch672]

It looks like the +/- 12v for the Control Pilot does not get generated on the EVSE-Shield, so one needs to supply both?

If one supplies only +12 to the OpenEVSE, that powers the Relays and is used to provide 5v for the circuitry, and the -12 for the Control Pilot?

Gary, I believe that +/-12V gets generated on part # D107E, see this PDF schematic, look on the "Pilot" section on the upper right, I don't think there is any difference between the OpenEVSE schematic and the OpenEVSE shield version:

http://open-evse.googlecode.com/files/Open%20EVSEv1_1gfci.pdf" onclick="window.open(this.href);return false;

 

[garygid]

Yes, you are right, Thanks.
I did not read the blurry EVSE-Shield circuit correctly.
I edited my post above to correct it.

 

[nr56]

Chris,

In the "photo of programming setup" image you have uploaded to OpenEVSE, you seem to have two programming cables attached to the board at once. Why is this?

Also, can you post a link to the exact Adafruit display and "backpack" you're playing with.

Trying to keep up with you

Thanks for this project,
Richard

Richard,

Read this first
http://code.google.com/p/open-evse/wiki/Stepbystepinstructiontouploadcode" onclick="window.open(this.href);return false;

I made the photo you are referring to just as an illustration for the orientation of the programming cable - this is the flat gray-ish cable.
The other cable (the one with the multicolor wires) is the FTDI usb adapter cable which allows you to monitor status (or change parameters if the uploaded program allows it) with your computer.

 

[chris1howell]

I designed a very small Open EVSE add-on board the other day, it started off as a joke but I may actually build the board.

Is you can imagine I get a lot of E-mail and PM asking... Can I add buttons, switches, jumpers (for setting current), LCD, LEDs (to show current setting), inhibit inputs...etc.

So as a joke I designed the do almost everything i2c add-on. In theory you could add 7 of these to the OpenEVSE. I took a common 16 input/output i2c port expander and used 8 as inputs and 8 as outputs. The inputs have resistors so you can add switches, jumpers, buttons... The outputs go to 1 RGB LED and 4 3mm LEDs OR leave the LEDs out and add a standard 16x2 LCD...


Thoughts...?

 

[eHelmholtz]

I designed a very small Open EVSE add-on board the other day, it started off as a joke but I may actually build the board.

That is so cool! but as a practical EVSE, your open EVSE board with the newly designed 12V supply and LCD is a thing of great beauty and joy!

 

[mrbigh]

I designed a very small Open EVSE add-on board the other day, it started off as a joke but I may actually build the board.

Is you can imagine I get a lot of E-mail and PM asking... Can I add buttons, switches, jumpers (for setting current), LCD, LEDs (to show current setting), inhibit inputs...etc.

So as a joke I designed the do almost everything i2c add-on. In theory you could add 7 of these to the OpenEVSE. I took a common 16 input/output i2c port expander and used 8 as inputs and 8 as outputs. The inputs have resistors so you can add switches, jumpers, buttons... The outputs go to 1 RGB LED and 4 3mm LEDs OR leave the LEDs out and add a standard 16x2 LCD...


Thoughts...?

Not to discurrage you on your efforts but, isn't what you are describing almost the same than the adafruit I2C LCD shield with buttons?

 

[mitch672]

Interesting concept, but I think the AdaFruit RGB LCD Shield is enough... that has 4 "direction buttons", 1 "select" button, should be enough to write the user interface for setting the current.

You could make an LCD shield version that would "line up" with the OpenEVSE card pins, so it could be plugged into the top of the OpenEVSE card, elliminating the 4 wires, but probbaly not worthwhile either, thats not much wiring to start with.

Another concept would be to just design a version with everything on 1 PCB, LCD display (done the same way as the AdaFruit, with the I2C expander, as ThinWing suggest below, remoting the buttons would work better for this design, so design to use PCB switchs, and extend contacts to a header, so you have a choice when building it.), stuck relay detection, a place to mount the AC to 12VDC power supply module, in other words, the entire EVSE complete with display, on a larger PCB. Then everything is done, just add the external relay for HV switching (or relays, if you want detection and the ability to disable the 240V output to the J-1772 connector), and the current sensing CT.

 

[Thinwing]

looks good Chris...The only problem with using the buttons on the adafruit rgb backpack is mounting the display and getting access to the buttons(drilling holes?)The "super breakout mini board) would allow remote mounting of all leds,buttons,lcds,vfds etc in a nice esthetic professional enclosure.The two nema boxes I currently use are pretty tight...I am currently looking for something a little bigger,as the 20x2 vfd display with its pcb is to big...anyway great work in progress and I hope to post pics of my latest evse in a week or so..kpc

 

[DaveEV]

Another concept would be to just design a version with everything on 1 PCB, LCD display (done the same way as the AdaFruit, with the I2C expander, as ThinWing suggest below, remoting the buttons would work better for this design, so design to use PCB switchs, and extend contacts to a header, so you have a choice when building it.), stuck relay detection, a place to mount the AC to 12VDC power supply module, in other words, the entire EVSE complete with display, on a larger PCB. Then everything is done, just add the external relay for HV switching (or relays, if you want detection and the ability to disable the 240V output to the J-1772 connector), and the current sensing CT.

+1 - this would put everything on a single PCB which is nice and pretty much gets you a pretty sweet EVSE.

As mentioned, the Adafruit PCB has the issues with mounting the PCB and buttons, remote buttons would really help. Though I imagine people have worked around that issue...

 

[mrbigh]

As mentioned, the Adafruit PCB has the issues with mounting the PCB and buttons, remote buttons would really help. Though I imagine people have worked around that issue...[/quote]

Not more involved than a few thin cables from here to there..........

 

[chris1howell]

The thought for the add-on board was for a EVSE without an LCD. You could still set current and get feedback on the setting, I added LCD support beacuse it cost only $0.25, 1 resistor and 1 transistor. The onboard button switch could toggle between 4 current settings indicated by the LEDs or you could use jumpers for "field selectable" current.

I may do a all in one device, I have done a couple layouts but have been unhappy with the results.

 

[mitch672]

Chris,

yes, that would work having 4 LEDs and a button to cycle through them for current setting, it is however very low tech..I'm not sure the cost of a $10-12 2x16 RGB LCD, and the few dollars for the 16 line I2C chip is going to make much of a difference in the total cost of the project, especially when we still have to pay $261 for the ITT J-1772 30A cable. Of course the other reasons for not wanting a fancy LCD display, could involve weatherproofing (difficult to seal the enclosure with that large LCD), so LEDs might be preferable.

If you build a combo board, you could make a mounting place for the LCD/I2C chip, but not everyone would use it... Then if you brought the I2C chips input and outputs over to a header, the user could wire up switchs/LEDs to it (aka your add on board you posted above), or you could place the 4 LEDs on the board as well, and the user could decide what they want for controls, full RGB LCD display, or just a 4 LED discrete display.

Lots of ways to go with this, but in the end you are still going to have the one of the best, lowest cost J-1772 controls

 

[fotajoye]

Ah!, Yes! we are still waiting for a Sugardaddy to buy 1000 J1772 cables from China and sell them for a fair price in the U.S.
I fear it will be somewhat of a long wait unless someone wants to take a chance.

 

[Thinwing]

Sugardaddy...not likely I am afraid :roll: On a new thought,I am building my second evse.This time I am using a 6in square nema aluminum enclosure with out breakouts...sold by allied electronics...I will be milling out the slot for a lcd or vfd and mounting behind a clear lexan window.Single switch and led besides a Glandnut to protect cable.I than thought what this project needs is a LOGO...something like a computer cut vinyl lettering with a large "O" open at the middle ,than EVSE through the center...comments??kpc

 

[chris1howell]

For those on the waiting list for boards a big thank you for waiting so patiently. On Friday I received the blank boards from DorkbotPDX after an unusually long wait (5 weeks instead of the normal 2). I spent the weekend building the boards, loading the latest firmware and testing. I have 12 boards ready to go which should get through most of the backlog and another 9 blank boards on the way.

1 Grt Art Shipped
2 skywagon Shipped
3 skywagon Shipped
4 skywagon Shipped
5 caglassmith Shipped
6 highdesertdriver
7 ollie Shippedi
8 woodust Shipped
9 Darkstar Shipped
10 Jwest
11 danny Shipped
12 danny Shipped
13 Graham Shipped
14 Graham Shipped

3rd Batch...
1 Tony Shipped
2 KillaWhat Shipped
3 mpt Shipped
4 garygtx Shipped
5 3ric
6 3ric
7 Kline Shipped
8 jjlink Shipped
9 clarktec Shipped
10 mcochris
11 Mulla
12 BolenGM
13 matt
14. Matt
15.Luesse
16.terry

I will be sending PM – E-mails today…

Can anyone guess what the top 3 boards are?