Tag Archives: Evse

DIY Recall part 2

Yesterday I got a phone call from the electrician about replacing the cable for the Bosch EVSE. It went something like this:

“Hello I’m electrician XYZ calling about that EVSE cable. We can schedule a time for me to come out and swap them out.”

“Oh yeah that cable–I’ve already did the job.”


“Yeah, the instructions were so clear it seemed pretty easy to do. Took me about 15 minutes.”

“It works?”

“Yup right after the swap out I let the car charge for over an hour and nothing blew up.”

“Ok, I may have some paperwork for you to sign.”

Shortly after I got an e-mail from them with the paperwork. The signatures required basically acknowledged that the work was performed to my satisfaction! LOL Sure it was since I did it.


DIY Recall

Yesterday my Bosch replacement cables arrived for the Power Xpress EVSE. To my surprise the kit included detailed, clear instructions on how to replace the cables so I did…

The first step was to remove the sticker covering the screws:
Power Xpress panel
The screws are the same square head screws that just about every RV in the world uses which meant that I already had the tool for the job.
Behind the Power Xpress panel
From there its loosen the terminal block screws to pull out the wires, remove the nut to disconnect the ground wire, remove the cable stay, and remove the tension nut at the very bottom.
Once the old cable is out you simply reverse the process to install the new one.
New Cable installed
Finally, plug in the car to test.
New Cable installed
I let the car charge for a good hour to ensure the connections were solid with no ill effects to the EVSE or the car (then I unplugged it and reconnected up the Juicebox LOL since that is my main EVSE).
Total time: about 20 minutes which included trips to/from the basement to retrieve various tools.
Now I await an interesting conversation with the electrician when they call: “Hello we’re calling to perform the cable swap out for your charger.” “Ok I’ve already performed the task, do you need the old cable back?” “What?” “Well the kit came with very clearly illustrated instructions and there was nothing indicating I should wait for the electrician…”

A PowerXPress “recall”?

Interesting, I got the following note in the mail from Bosch:
PowerXPress note
Here is the text:

Our records indicate that you are using your Power Xpress to charge an electric
vehicle(s) with a charging system that operates at 30A or higher. Recent
incidents have occurred in which customers have expressed concerns related
to the performance of the Power Xpress while charging at 30A or higher. Some
consumers have reported incidences of sticking or melting within the connection
between the charging station coupler and the vehicle inlet.
The. Power Xpress is designed to charge vehicles up to 32A. A new cable/coupler
assembly has been designed to address the customer concerns while charging
at 30A or higher. In an effort to secure your complete satisfaction, Bosch will
upgrade your Power Xpress with a new cable/coupler assembly — completely at
your convenience, and at our cost.
The division of SPX Corporation that originally designed and sold the Power
Xpress became part of the Bosch group of companies and now operates as Bosch
Automotive Services Solutions Inc. (“Bosch”). Therefore, Bosch will be addressing
your charging needs going forward, including the upcoming interaction with you
regarding your charging station.
A Bosch customer service representative will be contacting you within the next
30 days in order to arrange for this upgrade. We will coordinate with you to have
a Bosch certified electrical contractor visit your installation at a time of your
choosing to complete the exchange of the coupler and cable. Because the Power
Xpress was designed for field replacement of the cable/coupler assembly, this
repair will take less than one hour and will not disturb your installation or its
environment in any way. A licensed electrician will detach the existing cable/
coupler from the unit and simply install the new one.
Should you no longer own your Power Xpress, we ask that you forward this
message along to the new owner if possible, or provide the new owner’s contact
information if available.

If you have any questions in advance of our contacting you,
please call Bosch at +1 888 823-9877.
Bosch Automotive Service Solutions

This is interesting! You may remember that my coworker suffered from this very problem. A technician eventually did replace the cable in his unit at no cost. The issue must have happened to more than a few EV owners for Bosch to issue this recall.


Testing EVSE’s

From Inside EV’s: Testing interoperability of 11 different EVSEs.

This is something to keep an eye on, how well will the EVSE(s) you use stack up against all the others?

When I watched the video I noticed the exact same connectors on the power side of the EVSE’s that I’ve been using in my garage–given that they are in Plymouth, Michigan it wouldn’t surprise me if they purchased them at the same Home Depot that I did! LOL

Here is a link to more details about the study.




More on that melting..

Back in May I had mentioned that my coworker noticed the handle of the Bosch EVSE he was using was getting warmer and warmer (see post here).

After he had his EVSE and the charge connector in the car replaced all was well..or so he had thought.
Melted Vehicle connector

Above is his first vehicle connector before being replaced.

Changing out the EVSE eventually fixed the problem but not before the 2nd vehicle connector also suffered some damage. Unfortunately his dealer did not feel the need to replace the 2nd damaged unit.

Fast forward to last week: He gets in his car to go to work and is greeted by a strange prompt in the car: “Am I still plugged in?” Not thinking much about it he dismissed the prompt and proceeded with his commute. At work everything went nuts: The dash board started flashing many errors and warnings, including the dreaded “Stop Safely Now” message and the car quit. He called Ford’s Roadside Assistance for a tow–which was very efficiently handled, he got text messages to his phone indicating which tow company was coming and when..if only other Ford operations worked so well. The tow truck driver even asked to see the owners manual to clarify how to tow the car.

Once the car was at the dealer he prepared for the worst (since most of his experiences with the dealer have been less than satisfactory). They replaced the charge plug and harness, the LED ring and the 12V battery in the car (With the damage to the old plug the car was left in a state where it thought it was plugged in and thought it wasn’t plugged in thus keeping the 12V electronics in the car alive enough to drain & damage the 12V battery which is why the car freaked out). The dealer even kept the car overnight after all the fixes were done “for observation” to ensure that all was well and working before returning it.

Happily after a weekend of putting 50+ miles on the car it seems to be back to its quirky self again, and plugging a charger in is no longer a delicate operation…

Here is hoping this is the last story I hear from him about car malfunctions! (He is now investigating a completely new EVSE.)



What is this Juicebox saved value?

When perusing the Juicebox source in a previous post I also noticed how it was calculating the “saved” value. If you are not familiar with the Juicebox saved value: On the premium Juicebox with a display it shows a $ saved value that increases as you use the JB.

What is this value? How is it calculated?

To begin with the Juicebox makes a few assumptions (constants declared in the code):

  • Price of gas $3.50
  • mpg of car to compare to 25
  • Price of electricity per kWh $0.12
  • Efficiency of the EV 300 Wh/mile

It then uses those values to come up with a “savings per kWh” value:

gas cost per mile = price of gas / mpg (3.50/25 or $0.14 /mile)

gas cost per kWh = gas cost per mile * 1000 / wH/mile ($0.14 * 1000 / 300 or 0.466 per kWh)

savings per kWh = gas cost per kWh – price of electricity per kWh ($0.466 – $0.12 = $0.346)

The total savings then is this savings per kWh value multiplied by the total kWh the JB has put into the car.

The total kWh is calculated by multiplying the input voltage, output current, and time interval (Watts = Volts * Amps, kWh = Watts over standard time interval–hours).

Much like my previous post this all is pretty straight forward math. The number it reports out may or may not be meaningful to you if your situation closely matches the configuration of the Juicebox (25 mpg prior car, EV burning 300 Wh/mile, etc.).

For those of us with the FFE, the Wh/mile value is more like 240-250 (about 15% more efficient) and, in my case since I drove an ICE Focus before the FFE, the mpg figure would be more like 30 mpg (about 15% more efficient as well). Which, for my case, the two differences pretty much cancel out making the $ saved value fairly accurate–if gas prices remain near $3.50.


Digging into the Juicebox

Since the Juicebox is open source we can pull back details about the design and poke around. In this post I’m going to give a look-see through the source code running on the Arduino board that runs the Juicebox.

The Juicebox code is a very simple loop running on the Arduino (an ATmega328P microcontroller equivalent). There is no RTOS running on the Arduino–just the Juicebox code. There really isn’t enough room on the chip to have a full RTOS; there is barely enough room there for the code that is running on it.

During setup/startup the code configures the Juicebox:

  • Configure I/O
  • Setup timers
  • Check for and Initialize display
  • Read the last clock value out of EEPROM (there is no real-time clock on the board so it remembers the last time it was powered up)
  • If the “A” button on the remote is pressed all the configuration parameters are reset to default
  • Checks for the presence of the remote (not sure why this is after the above check)
  • Calibrate the pilot signal: It will adjust the pilot signal based on temperature and voltage output
  • Determine the input voltage (120V or 240V)
  • Perform some diagnostics on the GFI circuitry

Now its finally ready to go. You can pretty much see/hear this sequence being performed when the Juicebox is first plugged in as it takes about 10 seconds or so to get through it all.

The main section of code is just a large loop. The loop repeatedly cycles through the following tasks:

  • Check for presence of a car and if it is charging
  • Manage a change in state from the previous iteration through the loop (e.g. car plugged in, car charging, charging complete, etc.)
  • Set the configuration to the new state (if changed)
  • Update the display (real-time status on charging)
  • If there is WiFi send some data out to the Web (EMW)
  • Check if a menu button has been pressed
  • Check if the GFI has tripped
  • Repeat

That is about it. Pretty simple operation but then I really wouldn’t expect a lot from an EVSE since it really has only two purposes: Provide power to the car and provide GFI protection.

One feature that I’d like to see in the Juicebox that it currently doesn’t do: Turn off the display after 5-10 minutes when not plugged into the car. There really is no reason to keep the display lit when not plugged in. (I’m not sure if this is even possible simply by looking at the source code–may have to take a peek at some circuit diagrams to figure that one out.)


Chargers are us…or rather EVSEs

I seem to be collecting EVSE’s lately! A year ago when I picked up the FFE–my first plugin car of any kind–I didn’t know what EVSE to get and just got the one the power company recommended as part of their installation deal. Now today I have a small collection of them:
EVSE Collection
On the left is my original Bosch/SPX PowerXPress unit which is proving to be a little troublesome. In the middle is a Clipper Creek LCS-25P. The far right is the newest of my four EVSEs (4th is the 120V one included with the car): An EMW Juicebox.

Now I didn’t really pay for all of them:

  • The Ford EVSE comes with the car (so yeah its cost is baked into the car)
  • The Bosch/SPX unit had a tax deal where my power company paid for almost all of it
  • I did purchase the LCS-25P as a Level 2 backup to the Ford EVSE
  • The EWM Juicebox I won right here for this blog!

Yes you read that right: I’m the winner of the myevblog contest from September/October last year. The Juicebox only just arrived today–I had expected it to take some time given that it is a Kickstarter project. So I finally have something to write about other than “I won!”.

(A note about the wiring in the picture above: The Juicebox is rated for 60A and thus its two cables are quite beefy. To get it to plug into my outlet and be “compatible” with some of my options I removed the 14-50P end of the cable and put a L6-30 plug on it. Since the cable was so thick I wasn’t able to put the strain relief on–yet. With the L6-30 plug it uses the same pigtail that the LCS-25 does. I only have it set for 27A.)

Lets take a look at the vehicle connectors for the four EVSEs:
EVSE Plugs
EVSE Plugs

Left to right the connectors are: Bosch/SPX, Clipper Creek LCS-25, Juicebox, and finally the Ford “convenience cable”. A few remarks about each:

  • Bosch/SPX: This one seems to be the cheapest design. A rubber overmold over some plastic with a small hole for drainage.
  • Clipper Creek: This is a very nice connector. In the second picture you can see the green O-ring used to seal the plug against the car. The cable has a Delphi tag and part number on it.
  • Juicebox: This connector seems to be the best of all four, similar sealing to the LCS-25 and a bit more solid feeling. It even includes a rubber dust cap.
  • Ford: The Ford plug is very similar to the LCS-25 plug in design and about the same quality.

On the whole they all get the job done, some quicker than others of course. The Juicebox stands out, though, because it has some extra features:
Juicebox display

The display shows the current power consumption and charge rate (above I’m charging at 240V, 27A and the Juicebox has put in 0.1 kWh into the car for the past minute).

You can set the max current level via a menu item (even adjust it while the car is charging–the “outC+” and “outC-” shown on the display above). If I had the WiFi adapter I could also setup a charge schedule in it similar to the Value Charge schedule in the FFE.

So far after about two hours of using the Juicebox it appears to be a very nice unit–albeit a little large case but does look cool like an AA battery.

More to come after I’ve used it a while…


Leveling up

To take advantage of an electric vehicle you really need a Level 2 EVSE installed at home unless your daily commute is roughly half of the vehicles range (I’m speaking of the “low cost” BEVs with a range of ~100 miles–a 300 mile Tesla Model S is a different story). At Level 1 charging rates a completely empty battery could take as much as 20 hours to charge–much longer than your average night time.

Level 2 EVSE’s can cost a few hundred dollars (the DIY versions) to up to about $1000. Do some research; you may find deals and/or rebates. For myself I found a $2500 rebate towards the price of the EVSE and installation from my power company. The deal also included me in the EV program for time-of-day rates on electricity (charging at night reduces my electricity cost by a factor of 4). The program was part of Bosch’s “Plug In Now” EV business (formerly SPX). Note 1: you can even search for incentives in your area on that link. Note 2: You need to have possession of the EV before you can use that program.

The installation process was pretty easy: They first send out a contracted electrician to quote on the installation (funny that it always seems to come very close to or above the $2500! at least from the few I’ve talked to who also did this). After the quote is approved by you and Bosch they order the EVSE. Once the EVSE arrives they schedule a date to come out an install it. Now the fun begins: You can start charging at Level 2 speeds (at this point you may not be billed for the EV separately yet as the power company has to then come out and install a 2nd meter).

My Bosch EVSE

My Bosch EVSE

Using a Level 2 EVSE won’t use any more power than the Level 1 EVSE: The car still charges to whatever battery level it has; it just does it faster. In many cases Level 2 charging is slightly more efficient and thus will use less power.

Now you may ask: What does that really do to your electric bill? Using all that electricity it must be a lot! (A question I just received recently) To that my answer is below: Exhibit A my EV electric bill for the first month:

First months electricity bill for the FFE

First months electricity bill for the FFE

Yup: One month of driving around in my car cost me a whopping $37.79! In our ICE Focus the same commute was costing me $200+ per month in gas.