E-MotorWerks JuiceBox - an open source 15kW EVSE

[chris1howell]

A few OpenEVSE builders experimented with the same relay back in May 2013. The general consensus was it ran too hot without active ventilation. It should be okay at 30a but I would be really careful at the 12 kw (60a) advertised.


Here is the thread with the discussion...
http://www.mynissanleaf.com/viewtopic.php?f=26&t=6546&start=1050" onclick="window.open(this.href);return false;

 

[ImpactVector]

Thanks!

This one has mr scratching my head. Wondering if I should change to a different relay/contactor?

 

[ImpactVector]

Thanks Chris!

Here is a video I shot showing the temperature of each parts. Looks like between the contactor's at the top gets the warmest. Since its under 100 I'm not very concerned but figured I would ask.


https://www.youtube.com/watch?v=RtOTG-xrXkg&feature=youtube_gdata_player" onclick="window.open(this.href);return false;

 

[ImpactVector]

Bump.. Any comments on temps?

 

[foldog22]

Bump.. Any comments on temps?

Hey ImpactVector, what you have here is great. Any chance you will write up a guide? I am a complete n00b to this stuff but would like to upgrade my Standard JB to something like this.

 

[ImpactVector]

Bump.. Any comments on temps?

Hey ImpactVector, what you have here is great. Any chance you will write up a guide? I am a complete n00b to this stuff but would like to upgrade my Standard JB to something like this.

Ya" give me a few days and I'll see what I can do.

Right now I'm in CA for work and have to get back to Atl when the ice thaws.

 

[772]

Just got this EVSE today (base version) and it seems to be charging fine (although the supplied J1772 plug is a tight fit). My question is how are people mounting/storing this EVSE? I saw some pictures of someone using command velcro strips to mount this to the wall. If that works, I'm all for it as I'd prefer to put as few screws into my walls as possible. The box does feel a bit heavy, and the screws on the back make it so the back is not flat, so I'm not sure how well the strips will work

Here is the pic I'm talking about:

http://priuschat.com/threads/emw-juicebox-level-2-charging-station.135144/#post-1930841" onclick="window.open(this.href);return false;

 

[Levi8than]

I would not mount with adhesive or velcro, but that's just me. Also, I LOVE drilling holes in my wall, it's one of the many perks of homeownership (like this: http://xkcd.com/905).

I mounted indoors so had no problem drilling holes in the box and mounting with lag screws into the stud.
My cord them goes outside through an RV access port: This guy: http://www.amazon.com/gp/product/B007H2RHQE/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
And I hung the charging end on my own variation of Joe's plug: http://erroneus.myevblog.com/buy-plastic-parts-here/

I highly recommend the plug with the hood to hang your cable on. I only redesigned it because I printed on a cheaper printer that couldn't handle the overhang his design has. You can look both designs up on thingiverse if you have a friend with a printer. Or order from Joel's site. His prices are very reasonable.

 

[772]

We own our home, but never invested in a drill

That's why I would prefer to try the solution that doesn't involve the drill first.

Also, I did plan to get Joe's plug, but I was going to get the angled one without the hood, as I thought the one with the hood did not have a latching point for the plug. Is there any benefit to the hooded version aside from the option of spooling the cord? I'm not sure I would be able to spool more than a round or 2 of this beefy cable (I ordered the 25ft 70A version so we would be able to charge at more than 30A in the future).

 

[Levi8than]

We own our home, but never invested in a drill

That's why I would prefer to try the solution that doesn't involve the drill first.

Also, I did plan to get Joe's plug, but I was going to get the angled one without the hood, as I thought the one with the hood did not have a latching point for the plug. Is there any benefit to the hooded version aside from the option of spooling the cord? I'm not sure I would be able to spool more than a round or 2 of this beefy cable (I ordered the 25ft 70A version so we would be able to charge at more than 30A in the future).

You can ask Joel directly. He's a member on this forum: jclemens
If you are hanging outdoors, the hood offers better water deflection. Indoors if you have somewhere else to hang your cable it may be unnecessary.

I believe all versions have latch point for the plug. I checked the stl posted on thingiverse (http://www.thingiverse.com/thing:154452), and it does contain the latch point.

And I have the same cable. Photo of my install is here (http://www.thingiverse.com/make:62717).

When I printed Joel's design (didn't order Joel's design, I printed it on a much much cheaper printer with crappy tolerances), I didn't like how snugly the cable fit. So I redesigned it to remove the inner circles and add some free space. I don't think this is necessary if you have a high quality printer like Joel's.

So my advice is to order from Joel because it just works and he spent a lot of time on this.

 

[maizester]

Hey there - I just discovered this thread today.I'm wanting to add a volt/amp meter to my JB like the one pictured in the beginning of this thread. Where did you get the meter and how exactly did you wire it in to the JB ? Maybe I missed something - thanks - Dave

 

[ImpactVector]

Dave ,
I got the display on ebay. Think it was !$20 or so.
Look for Ac amp meter. Just make sure it's 220v

The current side is from a circle that I ran one of the j1772 cables through. The power I got from the relay when it closes and feeds the car.

Easy mod. Takes 10 min!

 

[maizester]

Thanks for the ideas - How many wires does the amp/volt meter have ? Did you run it through a current sensor ? - Dave

 

[ImpactVector]

Thanks for the ideas - How many wires does the amp/volt meter have ? Did you run it through a current sensor ? - Dave

2 wires for power and 2 wires to the current sensor.

Very quick and easy!

 

[Levi8than]

It's been raining the last couple of days, and I expect it to continue. This is pretty much the first heavy rain since I installed my Juicebox. The juicebox is indoors, with the cable run out through a little door and the end being stored on a printed PLA hanger:

I'm not sure if sharing images this way works. Let's try it:

It's been working flawlessly since early January when I got it working. And now for the second day in a row, my car is reporting an EV system panic and not charging completely. The car is set to charge to 80%. Today I only got 75%, yesterday I only got 72%.
Do you think the rain is to blame? It's the only thing I know that has changed. And do I contact Nissan because there's an issue on their end, or look at the plug coming from my juicebox? Any thoughts? Everything I've looked at suggests that charging in the rain should be fine, and that the access door is properly drained.

 

[772]

We started having some charging issues today too, but we're not sure if it's the car or the EVSE. We set a charging timer and apparently charging does not start when it is supposed to. The dash lights do not light up at all when the EVSE is connected to the car, but apparently there are some clicks that happen. Last night, the car did not charge up at the normal time like it usually does. However, the timer can be overridden with the button in the car, and then it will start charging. So, I think it is likely something with the car, but I'm not sure what. Has anyone had an issue like this?

I will try with the trickle charge when I have a chance. For now, we can still charge, but not having the timer function is a bit annoying since we usually charge to near 100% daily.

EDIT: Checked on the car and it did NOT charge after hitting override, it just looked like it was. Very strange, will have to try a couple things out.

Turned off the charging timer and plugged it... looks like the car is charging now. Will check back in ~1 hour and see what happens. Still trying to figure out the issue with the timer.

EDIT2: Went back to check now (~10 minutes later) and there were no lights flashing and the car was not charging. Ugh... will check with trickle charging and Nissan EVSE tomorrow probably.

EDIT3: L1 charging works just fine... will confirm using a L2 Nissan charger at the local dealer and then contact EMW.

EDIT4: Decided to unplug the JuiceBox from the outlet and replug... this must have reset something in the EVSE as our car is able to charge again on L2. Not sure what changed but I hope it lasts...

 

[mitch672]

772, even "OpenEVSE" needs a reboot every once in a while, the microprocessor sometimes get hung up (usually from power line transient noise issues), its like rebooting your Windows XP machine, probably good to do once in a while

 

[772]

Thanks mitch.. my folks have been using this EVSE for about a month now and this is the first time we've run into this issue. Good to know that it's nothing serious.

 

[greenleaf]

I am thinking of get the JuiceBox. Since I don't want to upgrade the house wiring, can anyone comment how easy (or difficult) is it to limit the current draw to say 16A max?

 

[Levi8than]

I am thinking of get the JuiceBox. Since I don't want to upgrade the house wiring, can anyone comment how easy (or difficult) is it to limit the current draw to say 16A max?

Very easy if you have a way of measuring it. But be very careful because there is 230-240 volts live within in this box and it can kill you.

There is a yellow pot on the main board that you turn with a screwdriver to adjust the duty cycle, while the device is plugged into the vehicle.
And you have a choice. You either need access to a scope or a multimeter that measures duty cycle (like this: http://www.amazon.com/Extech-EX330-Autoranging-Multimeter-Thermometer/dp/B000EX0AE4/) or a current clamp (like this: http://www.amazon.com/Uni-Trend-UT202A-Auto-ranging-Clamp-Meter/dp/B005FSSKJA/) or both.

In the trigger wire case, set the vehicle to charge based on a timer so it doesn't begin charging as soon as you plug it in (and risk blowing your breaker or worse).
Then as soon as you plug in, the juicebox will report the current it allows to be drawn over the pilot line.
Following the formula on this page: https://code.google.com/p/open-evse/wiki/J1772Basics, turn that pot until the duty cycle reads 26.6% for 16Amps. Then cancel the timer (or set it whatever you actually need), and let it charge as expected.

Or with the current clamp, you'll need to actually have the vehicle charging. Not waiting to charge. So you'll need to set it conservatively low to avoid blowing the breaker.
This method is less exact and may require a short ramp-up period for the vehicle to react to your change on the duty cycle pin. And just read the current on the clamp and ramp up until you reach 16 amps.

I prefer both methods. Set the duty cycle first. Then confirm with the clamp at a few points during the charge cycle.

Then you're free to set the timer or whatever you need. The Juicebox will re-sample the pot every time it starts so your new setting is locked in. I put a little hot glue on mine. It's a habit I've developed over the years from working on electronics. It's easy enough to peel off when you need to change it, but it's strong enough to keep subtle earthquakes or people bumping the box from turning your knobs.

Or if you're not comfortable doing any of this, if you ask nicely when you place your order for an assembled JuiceBox, the folks at EMW may be willing to set the current for you. It can't hurt to ask.