OpenEVSE - Open Source Charging Station

[mitch672]

Gary, I can answer some your questions:

The difference is, the advanced PS has the ability to check for power on either leg, and determine if the EVSE is running on 120V or 240V, it can also be used to perform the "stuck relay" test (check for welded contacts), and also for monitoring if there is a valid ground. Chris has each leg readable on a digital input on the Arduino.

 

[garygid]

OK, the "Advanced" provides the same Power, but also provides "taps"
for reading the Hot-to-Ground voltages both at the EVSE input and output?

Is the circuit schematic for the Advanced Power Supply board available?

 

[mitch672]

OK, the "Advanced" provides the same Power, but also provides "taps"
for reading the Hot-to-Ground voltages both at the EVSE input and output?

Is the circuit schematic for the Advanced Power Supply board available?

Not quite. It has 2 sets of AC inputs, 1 set powers the actual power supply (the 12V converter module), the 2nd set of AC inputs is for determing L1/L2 (1 leg hot, or both), and is also used for the "stuck relay test" (the inputs should be made at the relay output where the J-1772 cable is connected), the stuck relay test is done at power up, with no vehicle connected. You can also determine in you are running L1 (120V only on 1 leg), or L2 (240V, both legs energized with 120V)

The downloads are here: http://code.google.com/p/open-evse/downloads/list" onclick="window.open(this.href);return false;

Here is an example EVSE built with the Advanced PS: http://code.google.com/p/open-evse/downloads/detail?name=EVSEwAdvanced_Power_supply.pdf&can=2&q=#makechanges" onclick="window.open(this.href);return false;

Here is the Advanced PS build guide: http://code.google.com/p/open-evse/downloads/detail?name=Advanced-Power-Supply-for-OpenEVSE.pdf&can=2&q=#makechanges" onclick="window.open(this.href);return false;

No schematic, but its a very simple circuit:

Chris is using a 22K resistor from each 120V leg to a "MID 400" AC detect IC (there are 2 identical sets of these, one for each leg), then that is connected to Digital input D3 and D4 on the Atmel Mega 328P.

Mid 400 spec sheet: http://www.fairchildsemi.com/ds/MI/MID400.pdf" onclick="window.open(this.href);return false;

 

[chris1howell]

Thanks Mitch for answering Gary's question...I could not have done any better.

I will be posting the schematic and board files very soon.

 

[mrbigh]

That will be very helpful to upgrade my Open-EVSE installation of previous version.

 

[richard]

..
I received the EVSE-Shield Kit,
and the EV-Emulator Kit. I will build it as soon as I get my Taxes filed. :roll:
..

I went for the instant gratification, so sadly I still have my taxes to file

I soldered the advanced power kit and the EV simulator last night. The only tip I can offer is to make sure your soldering iron is hot. I started with the temperature dial at 500°F. But I was getting too much globbing, and the solder wasn't wicking onto the solder pad nicely. Bumped it up to 550°F and the problem went away.

The power kit fits nicely under the OpenEVSE board once you've soldered a female header to that board (on the left side in the pic below).

Just did a basic test of the power kit (as per Chris' instructions). Plugged it into 120VAC and verified that it outputted 12V. I'm sure more testing methods will come later. There is a "Test" terminal on the board. Not sure what this is for (Chris?)

Here are some pics of the EVSE testing facilitated by the EV simulator. For more info on what's going on here, check out Chris' instructions. Notice the position of the EV simulator jumper(s) in each pic.

State A

State B

State C

Open Diode Check (actually this may be State D. I need to check again)

 

[eHelmholtz]

Such an elegant design! Daft question but where and how do you connect the J1772? (which seems oversized for such a small and well designed EVSE)

 

[chris1howell]

Nice job richard.

The test terminals will tap into the relay output for the stuck relay check plus L1/L2 detection and ground check. I posted the EVSE example and build guide the other day. They are here:

http://code.google.com/p/open-evse/...dvanced_Power_supply.pdf&can=2&q=#makechanges

http://code.google.com/p/open-evse/...-Supply-for-OpenEVSE.pdf&can=2&q=#makechanges

 

[DaveEV]

Such an elegant design! Daft question but where and how do you connect the J1772? (which seems oversized for such a small and well designed EVSE)

The picture doesn't show the DPST relay which switches on/off L1/L2 to the J1772 cord.

What you're looking at in the pics above is the 12v power supply and OpenEVSE.

The schematic on this page may help you visualize things: http://code.google.com/p/open-evse/wiki/ExampleEVSE" onclick="window.open(this.href);return false;

 

[richard]

Chris,

Does it matter which way the CT wires are connected? I figured it doesn't matter, but wanted to check.

Thanks

 

[chris1howell]

Richard, The two wires can be connected either way does for it matter. The CT does need to go all the way at end of the j1772 cable after the relay and after the test point.

 

[mitch672]

I have completed assembly of my 30A L2 portable OpenEVSE, pictures are on the enclosed link.
I used an L6-30P plug on 10' of 10/3 SOW 90C cable, I also constructed several adapters, L6-30R to 10-50 (RV parks), L6-30R to L6-20P (for use on L6-20R 20A 240V outlets), and an L6-30P to a Standard 120V male (when no 240 is availble).

The NEMA enclosure I found fits all of the components perfectly, allowing you to mount all of them (they do not need to be "stuffed" into the box), they are all mounted, and the unit is also fused with dual 30A slowblow 3AB fuses.

I am listing the DigiKey part #'s,for the enclosure, mounting plate, 30A fuseholders and 30A fuses, as I had trouble locating the "perfect" enclosure (not too big, not too small, not too expensive), and 30A 240V capable fuseholder/fuses, as I assume I might get some questions as to where I got those parts..

They also make a matching bottom plate, to mount everything on, so you don't need to make extra holes on the bottom of the box. The box of course also has a clear plastic cover, allowing you to see the AdaFruit RGB LCD display, and all of the electronics, and its hinged, so when you occasionly need to adjust the current, you can open the lid, and adjust it. It also has 2 latches to keep it closes, and even a place for a padlock to lock the cover closed.

Pictures: http://s461.photobucket.com/albums/qq333/mitch672/OpenEVSE/" onclick="window.open(this.href);return false;

DigiKey Part #: 377-1787-ND, BOX NEMA ECONOMY 5.9X5.9X3.54, $20.62
DigiKey Part #: 377-1939-ND, PANEL INTERNAL 4.9" X 4.9", $4.80
DigiKey Part #: F1779-ND, FUSE 250V SLO-BLO 3AB 30A, $1.74 each
DigiKey Part #: 283-2850-ND, FUSEHOLDER 1/4" 30A 250V PNL MNT, 5.43 each

 

[mrbigh]

I have completed assembly of my 30A L2 portable OpenEVSE, pictures are on the enclosed link.

Mitch672, after hard wiring the Adafruit RGB display, have you reloaded/updated any software to make it work, or Chris already supplied the necessary code onto the micro in the last batch of PC Boards?

 

[mitch672]

I have completed assembly of my 30A L2 portable OpenEVSE, pictures are on the enclosed link.

Mitch672, after hard wiring the Adafruit RGB display, have you reloaded/updated any software to make it work, or Chris already supplied the necessary code onto the micro in the last batch of PC Boards?

Yes, he sent some test code that shows the EVSE states on the display, and changes the display color, so the display part is functional, and yes, I have a USBTiny programmer, to reload code as needed.

Its not released yet, and the code for the current selection is not done yet, and also the stuck relay detection/L1 or L2 detection either. Its still a work in progress, but the EVSE still works.. all good things in time

 

[garygid]

Looks like a nice box.
Links to the Digikey Parts, for easy viewing:

1. http://search.digikey.com/scripts/DkSearch/dksus.dll?site=us&lang=en&keywords=377+1787+nd" onclick="window.open(this.href);return false;
2. http://search.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&site=us&keywords=377-1939-ND&x=12&y=16" onclick="window.open(this.href);return false;
3. http://search.digikey.com/us/en/products/0326030.MXP/F1779-ND/778640" onclick="window.open(this.href);return false;
4. http://search.digikey.com/us/en/products/BK%2FHKP-R/283-2850-ND/1024094" onclick="window.open(this.href);return false;

 

[Barbouri]

A big Thanks! to Chris and the many contributors to Open EVSE.

I have finally finished my Open EVSE project that was started back in November 2011.

I am using one of the Adafruit VFD 2X20 SPI displays and the thru-hole circuit board.
Ordered the ITT J1772 cable from Avnet.

Ready - not connected to EV

Ready - Waiting for EV

Charging

Greg C.

 

[chris1howell]

Great job, Greg!!!

 

[garygid]

Very nice.
More detail on (and links to) the parts you used, please?

I want to do a very similar project as an adjustable-MaxAmps
portable unit, and possibly one for my garage.

 

[chris1howell]

I want to do a very similar project as an adjustable-MaxAmps
portable unit, and possibly one for my garage.

Gary... I have news on adjustable-MaxAmps, lincomatic has gaven his permission to include his Button Menu code in OpenEVSE. I will be releasing a new version 0.5.0, which included the additional safety features and Adafruit RGB LCD support in the next day or two. Next, I will start working on 0.6.0 to include the Button Menu code and enhancements to the Commamd line interface.

 

[garygid]

Chris,
As usual, excellent work, my friend.

I am working on adding GPS track Logging to CAN-Do, and possibly also adding a Bluetooth connection that could monitor the LEAF's CAN-bus and "request" that your BT-capable EVSE stop charging (at any selected SOC/GID level).

Assuming Discovery and Connection get done somehow, any thoughts on what CAN-Do would need to send?