Portable 40A EVSE for $361 versus Leviton for $1500

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When the software engineer tuned the signal he unplugged the unit and hooked up a rheostat that he had brought. He first set it to approximately 110 volts. He then powered the unit via this transformer. Once the signals were spread apart by adjusting the pot, he then raised the transformer voltage to almost 265 volts in insure that the bottom signal never overtook the top signal. He was then satisfied that the unit would work without any further problems. He mentioned that as the unit heated up the signals got closer together and that was why it would work for a bit then stop. I should have asked for more details. By the way no car was plugged in during this adjustment. He is one of the folks who worked with tesla to design this unit. He might be helpful.
 
Great video on the Juice Box Premium. Had I not gotten such a good deal on the Leviton 40 amp, then the Juice Box Premium would have been my choice. It has a lot of features that I think make sense. I like the idea of being able to access the unit via the internet. Excellent product.
Manny
 
drmanny3 said:
Great video on the Juice Box Premium. Had I not gotten such a good deal on the Leviton 40 amp, then the Juice Box Premium would have been my choice. It has a lot of features that I think make sense. I like the idea of being able to access the unit via the internet. Excellent product.
Manny

Thanks Manny for your kind words!
 
I spent the better part of the weekend researching the EMW JuiceBox and decided to pull the trigger on a pre-assembled base unit with 50A/32A I/O cables. A fairly bulky order, but only $20 for shipping.

What do I like about the JuiceBox? It is highly versatile and more importantly portable with its 6' long, RV style (NEMA 14-50P) input cord. I ordered the basic unit which is quite compact in its rather plain looking, but all aluminum weather resistant case. It can be adjusted to any output current limit from 0 to 60A in 1A increments. There is a trimpot on the PCB for this purpose, although I wish this adjustment was accessible via a small "capped" hole on the cover and there were incremental detents to aid in the setting.

As far as other available options, I decided to get the WiFi add-on. I feel this adequately bridges the gap between the Premium unit and the base model at the lower price point. EMW has an Internet accessible server to manage historical and near real time charging information for each JuiceBox registered user. The user interface hopefully should soon be available via an app on my iPhone.

The price (sadly, no longer offered via Kickstarter) is about the lowest for a future proof, plug-in, "portable" L2 EVSE capable of charging at 15kW (240V at 60A). EBM is located in the SF Bay Area and the founder has PhD in Physics, specializing in high power electronics and EV conversions over the past few years. They have a decent website that describes all their products and how to order. I asked a few questions about the JuiceBox via emails and got responses in the same day even on the weekend, so I'm anticipating stellar customer support.

I believe UL Approval is in the works, which is no small feat for ANY a company only in its infancy. As has already been stated, GFCI is now in the design even for the basic product.

All things considered, the JuiceBox looks to be an outstanding product for any at home or "take-it-with-you" charging applications.
 
The Juicebox folks have done a great job getting the word out about their products. I like that it's open source but in my opinion, its design and usability needs more tweaking. I find the OpenEVSE platform truly open source with years of field trial and a design that is elegant. It can be built with current up to 80A. Here's a 40A build using the same relay as the juicebox does (yes, I can set it to 60A but I just don't think it's a good idea) http://myrav4ev.com/forum/viewtopic.php?f=9&t=1013 Regarding the juicebox basic, as I understand it you may want to buy Nick Sayer's EV Sim Mark II to help set the current http://myrav4ev.com/forum/viewtopic.php?f=9&t=1013&start=85 since it's difficult to do for reasons you mentioned above.

The other issue that makes me take some pause about EMW products even though I think Valery (the founder of EMW) is doing some exciting work (He's got an extended traction battery with quick charging going in his Rav4EV) and seems to be a nice guy, is that safety does not appear to be a priority. We all know about the GCFI not being included initially and then there was the potentially dangerous version of getting 240V from 120V outlets which he sold for $50. http://myrav4ev.com/forum/viewtopic.php?f=9&t=1023&start=14 At least Valery does respond to criticisms well, adding GFCI as above and removing the hot 120V to 240V Y adapter as a product from his website.
 
Thanks guys for your feedback - we pay very close attention and try to address all constructive feedback points.

A lot of people commented on current setting interface in the Base Edition. This is actually a non-trivial engineering task. We can of course drill a hole in the case. In fact, the existing PCBs already have a landing pad for a trimpot with externally accessible dial. The problem is that all of these solutions result in compromising water-tightness of the enclosure. For the initial releases, we have decided that keeping the box waterproof is the right tradeoff. The Base Edition is often used as a portable device, exposed to the elements under arbitrary angles. So we need water protection from all sides and under all working conditions. Hence the tradeoff. To my knowledge, there is no waterproof enclosure yet readily available for OpenEVSE. And _definitely_ not the one which is both waterproof and allows pilot signal adjustment.

If remote adjustment of the output current is very important to you, you can achieve this with Premium Edition today (smooth pilot control is performed via a wireless remote that does not compromise water resistance of the box). I do realize that Premium is not quite portable, though.

We are working on this and other issues as we speak and there will be better options later this year. And this brings me to the next point why you should support EMotorWerks - we are extremely aggressive and quick in innovating in our products. We are all over the forums, social nets, and other places where you guys are, and we listen very well. I have Six(!) EVs in my household - a Leaf, a RAV4, a Karma, a converted Fiat Spider, and two converted BMW 3 Series. We are very passionate about the EV Charging infrastructure and have plans (and existing products) that go way way beyond just EVSEs. By supporting us, you are helping us make a difference at scale.

We think that to solve the infrastructure problem, we need not 1,000 inexpensive units out there (which is already 2x of what OpenEVSE has) but 100,000. Otherwise, we have failed to make a difference. We want to make every other EVSE maker to drop their prices because we think that it's ridiculous to have a $1,000+ EVSE without any smart functionality. Says Jeff Bezos (Founder and CEO of Amazon): "I see a competitor's love of margins and other financial 'ratios' as an opportunity for Amazon since the competitor will cling to them while I slice through them like a hot knife through butter". That's exactly how I think and I invite you to join this way of thinking.

PS. Relay ratings of JuiceBox have been a subject of many posts. I always repeat that they were tested by us over many hours at 80A (their rated power). And then we derate the unit to 60A. The relays are made for us in China with silver-plated contacts. What do you guys want me to do to stop these ungrounded challenges to our choice of this component? A thermal video of a 60A run? 80A? 100A? Let me know & we'll do it. But PLEASE unless you have the data, don't claim to know.

Thanks,
Valery
 
EVSEupgrade has an interesting solution for pilot adjustability that preserves the integrity of the case: Use the button on the J-handle itself. You insert a "programming tool" (ok it's a bent up paper clip) into both the pilot and proximity slots of the handle to put the unit in programming mode. Then you push the handle button 1 time for each amp you'd like.

This in concert with some sort of display for feedback (which needn't sacrifice case integrity - you could use a clear lid for the case) gives easy field adjustability. On the EVSEupgrade unit programming mode can also be used for other things, including locking the device with a security code that would render it useless if stolen. I love this feature of the EVSEupgrade, but unfortunately you can't easily get that in a 40a-capable unit yet (it only goes to 20a or 25a if you're willing to "live dangerously".)
 
Valerun, fwiw, the first L2 EVSE I owned (for Chevy Volt) was also a somewhat portable and "adjustable" unit. I think it was called Power Express sold by "SPX", and authorized by GM for use with the VOLT. I believe it was considered acceptable for outdoor use and may have been UL listed. It was a "plug-in" unit same as the JuiceBox with an optional AC input cord.

Funny thing is, unlike the JuiceBox, it had a small hole in the front cover plate for the output current limit adjustment. It had a gasket under the plate and several screws around the perimeter to securely seal it in place, and there was a piece of hard plastic plugged in to that adjustment hole to seal it when not being used. Underneath, inside the case, soldered to the PCB, was a rotary dip switch with about 6 different detent positions that corresponded to various output current limits. That plastic cover plug was hard to get out of the hole without a small flat bladed screwdriver to pry it out. It was meant to "seal" the hole and certainly seemed to do so quite inexpensively.

Of course, it the user left the hole plug cover off, it would have been with the understanding that the unit would not be suitable for outdoor use. I mounted this L2 EVSE inside my garage, but after setting the current limit, put the hole plug back in place. After I got a RAV4 EV, I got another higher power L2 EVSE made by Leviton, because the Power Express was only compatible with the 3.3kW charger in my VOLT. The maximum output power rating was 24A, because the J1772 output cable's rating was 30A max. My Leviton L2 EVSE is rated at 32A (7.7kW), and is much more suitable for charging the RAV4 EV.
 
Dsinned said:
Valerun, fwiw, the first L2 EVSE I owned (for Chevy Volt) was also a somewhat portable and "adjustable" unit...
Sounds like the Bosch (née SPX) Power Xpress, no? I think earlier versions could be set to 32a but the included J1772 cordset could only handle 30a, so you had to derate it to 24a; but it looks like they've taken care of that now by adding a 30a setting.

I came very close to buying one of these back when I got my Leaf (and when they were $200 cheaper) but was scared off because of some reported incompatibilities with the Leaf's timer. I think I saw a post way back when where someone mentioned a compatibility problem with the Rav, too, but that's probably been taken care of by now.

EDIT: Found that thread. Tgreene reports that the compatibility problems with both Leaf and Rav have been resolved; and apparently he bought his Power Xpress from you, Dsinned, so we probably are talking about the same thing!
 
Yep, that was it! Thanks for the clarification. A lot of similarities between what SPX designed and EMW's JuiceBox except for their power ratings and the latter with its Arduino based internals, has way more bells and whistles. Also, right you are about the Power Xpress EV incompatibilities, which according to 'tgreene' have now been addressed with firmware updates. However, there were no such "updates" available when I owned the same unit.

I think the length of time it takes to recharge an EV is a critical factor in deciding which EVSE to get for home charging applications. The JuiceBox seems to have that covered quite well for the price. Even the cost of a JuiceBox "fully assembled" and fully optioned, is competitively priced. Imho, it is a very versatile, combined L1/L2 EVSE with its universal 100V to 240Vac input and adjustable current output up to a full 60 amps!

Valerun, on your website, when ordering a JuiceBox, it says the 25' 32A J1772 output cable will ship during the first half of July. Is that still accurate?
 
valerun said:
. To my knowledge, there is no waterproof enclosure yet readily available for OpenEVSE. And _definitely_ not the one which is both waterproof and allows pilot signal adjustment.

We think that to solve the infrastructure problem, we need not 1,000 inexpensive units out there (which is already 2x of what OpenEVSE has) but 100,000. Otherwise, we have failed to make a difference. We want to make every other EVSE maker to drop their prices because we think that it's ridiculous to have a $1,000+ EVSE without any smart functionality. Says Jeff Bezos (Founder and CEO of Amazon): "I see a competitor's love of margins and other financial 'ratios' as an opportunity for Amazon since the competitor will cling to them while I slice through them like a hot knife through butter". That's exactly how I think and I invite you to join this way of thinking.

@valerun

Your information about OpenEVSE is grossly inaccurate.

Quick Points:
-OpenEVSE has shipped 1500+ units to date (500+ OpenEVSE v4, v5, v6 and v7, Arduino shield - 1000+ OpenEVSE PLUS varients)
-Production was increased by 2.5x to meet demand in the last couple months
-OpenEVSE does ship a outdoor enclosure AND yes current is externally adjustable

OpenEVSE was founded in 2011 when EVSE prices were 1200+ (my quote from AV was $2800 and the circuit was already in place). I believe OpenEVSE along with EVSE upgrade took many early customers away from the big boys and priced dropped fast. Sure maybe today 100,000 units needs to be sold to make the same impact but I believe plenty of significant impact was made by OpenEVSE.

To date 1500+ units have shipped, 500+ had shipped long before juicebox was even announced and the 1000+ mark was reached before Juicebox Basic customers started getting their first units. Demand is increasing, production was increased by 2.5x to meet the demand of customers and bulk orders. Commercial units based on OpenEVSE are available all around the globe (France, Israel, Netherlands...).

OpenEVSE does ship an outdoor enclosure, it is based on a die-cast aluminum enclosure form Hammond Manufacturing just like the Juicebox basic (but much smaller). There are 4 penetrations on the base and 4 on the lid, they are flush mounted captive fasteners, both parts are completely sealed during the powder coating process. The LCD window has a laser cut silicon seal, laser cut acrylic window and a powder coated Aluminum pressure plate. The button is a water proof and lit.

Current (and several other options) can be adjusted using the waterproof push button. Current can also be dynamically adjusted using the OpenEVSE remote API, several users adjust current dynamically based on a solar system output. I can adjust current and upgrade firmware on my personal unit using SSH.
 
@Chris, Thanks for stopping by and chiming in so that the information is accurate. I thought Valery was confused about details of the OpenEVSE so I'm glad you clarified a few things.

@Valery, Thanks for responding to my post; while you can see that I prefer Chris' OpenEVSE platform, I really do think that you're doing some fun stuff. But as I said above, I do have reservations about some of the products that you had on your site, especially the Y type 120V to 240V adapter without relays. Still, the juicebox has promise and regarding the relay used in it, I freely report that I'm using the same one in some of my OpenEVSE builds and like it but I find it gets too hot for my comfort at 60 to 80A so I usually limit it to 40A (which is what the Rav4 can pull anyway).
 
Thanks Chris for you corrections. I remembered you mentioned 500 units number before in one of your posts late last year so I used that. Should have checked.

Anyway, my point stays - we need 100,000 of these out there, not 1,000 or 2,000. How are we going to do that?
 
Dsinned said:
Valerun, on your website, when ordering a JuiceBox, it says the 25' 32A J1772 output cable will ship during the first half of July. Is that still accurate?

Yes, this is accurate. The ship with a batch of 300 J1772 cables is at sea already.
 
Valery, thanks for the clarification. I guess this means I will have to wait a couple weeks to receive my order. NP.

I have another couple of questions for you . . . since I ordered a Basic JuiceBox Unit with WiFi option, how do I use the WPS feature? Is there a WPS button on the WiFi module accessible only from the inside of the basic unit case? And if I order the FDCI option, do I have to be an Audrino programmer to use it? With it connected to a laptop, will this option allow me to precisely set the current limit with built-in, straightforward, menu driven commands from my PC?
 
Dsinned said:
Valery, thanks for the clarification. I guess this means I will have to wait a couple weeks to receive my order. NP.

I have another couple of questions for you . . . since I ordered a Basic JuiceBox Unit with WiFi option, how do I use the WPS feature? Is there a WPS button on the WiFi module accessible only from the inside of the basic unit case? And if I order the FDCI option, do I have to be an Audrino programmer to use it? With it connected to a laptop, will this option allow me to precisely set the current limit with built-in, straightforward, menu driven commands from my PC?

You would open the case and there will be a button on the PCB, yes.

FTDI allows you to connect from Arduino IDE and launch Serial Monitor from Arduino. Upon power up, JuiceBox will print its settings every ~1 second. You can then adjust current via trimpot and observe changes in Serial Monitor. No coding required.

Thanks,
V
 
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