OpenEVSE - Open Source Charging Station

[VegasBrad]

Great work Chris! I was hoping someone would develop an app and the code so charging could be checked on via a smart phone. I couldn't swing the payment for the S LEAF so no car wings service, no way to know the charge status unless it's at a charge point public station.

I just ordered my components to build my custom open evse from you. I got interested in open source evse's after seeing the juicebox, but I really like the open support of your products and your website!

 

[GlennD]

I'd like to build a evse that is adjustable with a rotary selector switch, or a ten turn pot with a display showing the amps it is set for. I want one I can use on the road that is easily settable.

You could do that with a JuiceBox basic and a EV Sim 2. You would need to remote R25, the L2 Pilot adjust.

To me it would be better to go with an OpenEVSE unit with the table edited for 1 or 2A steps. On the units I build I edit the table from 10A to 50A in 2A steps. Most current J1772 cables stop at 50A since there was overheating problems at higher currents. If I wanted more entries I could set it for 1A steps.

The advantage of the OpenEVSE is that the steps are firm and that they will not jump around.

 

[AlanSqB]

Great work Chris! I was hoping someone would develop an app and the code so charging could be checked on via a smart phone. I couldn't swing the payment for the S LEAF so no car wings service, no way to know the charge status unless it's at a charge point public station.

I'm kind of surprised that nobody has taken the canbus info and used an arduino or raspberry pi to send out telematics info via wifi or cellular shield.

I was thinking of setting up an RPi in the car to view the Leafspy type information locally via a small touchscreen, but then also add wifi so I could see the info via a web-page when parked at home. Could also then add another RPi to interface with the EVSE for control purposes. Then I could tell the EVSE to stop charging when the car reports >80%.

Just something I've been thinking about. Not sure if anyone has already done it. The car RPI could even be used with a cellular module or spare cell phone as a substitute telematics module.

 

[JeremyW]

OVMS is working on a port for the leaf...

 

[GlennD]

I programmed my test unit for RAPI. All the commands worked but for my use I see no need to remote the EVSE. For me it is there but I will Ignore it. Changing the display color was cool but why?

 

[AlanSqB]

The only "practical" thing I can think to use it for is to stop the car charging at 80% based on reporting from a custom gizmo in the car.

Impractical things I can think of:

• Touchscreen
  Remote control
  Disco lights on arrival to the garage

 

[GlennD]

The only "practical" thing I can think to use it for is to stop the car charging at 80% based on reporting from a custom gizmo in the car.

Impractical things I can think of:

• Touchscreen
  Remote control
  Disco lights on arrival to the garage

If you could program a device for the newer cars to stop at 80% or any value, now that would be useful. A touch screen is really a wow look at the cool interface.

 

[AlanSqB]

I'm thinking:
1. Car based module uploads bus data to M2X or some other IoT type server.
2. Module attached to EVSE by RAPI polls M2X for data.
3. EVSE module sends stop to EVSE when polled data reaches certain parameters.

Bonus: graphic display on EVSE attached module could display polled data on a screen.

Could skip the IoT all together, but I like the idea of logging the data online.

 

[kubel]

Ok, time for a new OpenEVSE. Last one didn't work out too well (just bad fuse implementation on my part)...

 

[GlennD]

Ok, time for a new OpenEVSE. Last one didn't work out too well (just bad fuse implementation on my part)...

I have a couple of the small junction boxes. I just can not just stuff the parts in them. It works but it puts a major hit on my neatness sense.

 

[kubel]

I have a couple of the small junction boxes. I just can not just stuff the parts in them. It works but it puts a major hit on my neatness sense.

Yeah, I have to rework everything. I prefer as small as possible, but even with partially external fuses, I barely have enough room to seal the box.

 

[asimba2]

Ok, time for a new OpenEVSE. Last one didn't work out too well (just bad fuse implementation on my part)...

Wow, that's even hotter than mine. Mine usually averages around 140 degrees inside the case, but I've seen temps at 150 degrees before I shut it down. I have re-crimped all of my connections and it made no difference, so I'm looking for upgrade parts to keep the temps down. From what I have gathered, replacing the fuses with breakers might be a good place to start.

 

[AlanSqB]

Post on another topic reminded me I don't need the module in the car to send SoC information. I can just have my Raspberry Pi poll the carwings website every 10-20 minutes and when it sees 80% SoC equivalent, send the stop via RAPI.

I can also have the RaspPi display SoC info on a web page or screen in the house.

If I only had some free-time!

 

[AlanSqB]

I like seeing the smaller builds. Have been thinking about what an in-line EVSE could look like in a long thin case similar to the OEM. I think I read Chris is also working on a smaller, limited current, setup so maybe that would help with this kind of build.

 

[eHelmholtz]

I like seeing the smaller builds. Have been thinking about what an in-line EVSE could look like in a long thin case similar to the OEM. I think I read Chris is also working on a smaller, limited current, setup so maybe that would help with this kind of build.

I've built a handful of these very portable OpenEVSEs for family and friends. The EVSE is enclosed in a 4x4x2 inch injunction box and I set it up for 120V/240V at 14A/16A respectively; I modified 1 to include an LED as below. Whilst I like the LED, I prefer no LED for the most portable of uses because LEDs can attract attention in public places.

 

[pilotnbr1]

I am curious about adding functionality and hardware that would allow the evse to share a single 240v outlet with a dryer. Obviously both loads would not be able to share the circuit simultaneously. Essentially it would be a smart "power strip" for the evse and dryer to share the single source. The user scenario would: car is presently charging, wife turns on dryer, evse stops charging car and resumes once dryer is off.

 

[min68]

I'm interested in "OpenEVSE 50A Deluxe Charge Station Combo" because of its real time display of current info.
However my home dryer outlet is 30A, and don't plan to upgrade it due to cost.
Can this be set to 24A or 20A to use 240V/30A outlet? price is same?

Edit: never mind saw 30A kit:
http://store.openevse.com/collections/openevse/products/openevse-30a-charge-station-combo?variant=830432221" onclick="window.open(this.href);return false;

But I don't see user manual in the link? Seems only build guide and source code.
Want to know all functions, output current adjust ability etc.

 

[dsinned]

This question about sharing an open source EVSE with a 30A dryer outlet has come up a lot recently. There is no inherent ability for any EVSE, as originally designed, to have this capability. It might not even be permissible with the electric code, but it can be done using an additional AC relay and a manual transfer switch. Automatic switching would be possible too, but slightly more complex. These additional components would NOT be provided within the EVSE as originally designed.

My understanding is that all open source EVSEs are "programmable" whether in H/W or F/W, and often both, with respect to current limiting. Depending on their output rating, most can be preset to limit at <=12A, 16A, 20A, 24A, 28A, and some at 30A or higher, while under load. The one exception, (although technically not "open sourced"), is the JESLA. I believe that one unfortunately, cannot current limit at 32A, probably because there is no NEMA standard for a single phase, 240V, "40A", AC outlet.

 

[TonyWilliams]

My understanding is that all open source EVSEs are "programmable" whether in H/W or F/W, and often both, with respect to current limiting, at <=12A, 16A, 20A, 24A, 32A and 40A, while under load. The one exception, (although technically not "open sourced"), is the JESLA. I believe that one unfortunately, cannot current limit at 32A, but that is probably because there is no NEMA standard for a single phase, 240V, "40A", AC outlet.

That's absolutely correct. There are no 40 amp electrical outlets, so no need for a 32 amp (80% continuous load of 40 amps) unit.

So, if you plug JESLA into your 50 amp outlet (NEMA 14-50R, NEMA 6-50R), you will get a 40 amp pilot signal, as is proper for a 50 amp circuit. But, if you use JESLA to plug in your LEAF, the LEAF will safely pull either 16 or 27.5 amps (for 3.3kW or 6.6kW, respectively).

There is absolutely NO REASON to limit the JESLA to 32 amps on a 50 amp circuit, therefore it's not done.

The history behind J1772 is that it was ALWAYS limited to 30 amps until Tesla Motors petitioned the SAE to raise the limit to 80 amps in the USA. For the record, the rest of the world doesn't recognize that. In Japan, J1772 is still 30 amps. Virtually all public J1772 charging in the USA is 30 amps. In Europe, "Type 1" (J1772) is also 30 amps single phase.

That's the only reason we even talk about 30/32 amp EVSE's, plus many of the J1772 cable assemblies are limited to 30/32 amps. Quick Charge Power offers J1772 plugs / cables in 32, 40, 50 and soon 80 amp assemblies.

 

[eHelmholtz]

That's the only reason we even talk about 30/32 amp EVSE's, plus many of the J1772 cable assemblies are limited to 30/32 amps. Quick Charge Power offers J1772 plugs / cables in 32, 40, 50 and soon 80 amp assemblies.

The other reason that people talk about 32A EVSEs is because there are 40A circuits with 50A outlets (which meet code) or hardwired.