While it’s pretty cool to have a classic factory built electric truck, one thing I don’t like is it’s NON-standard charge port. So, I set out to build an adapter so that I could charge in public and more conveniently at home.
The Ford Ranger EV uses an AVCON “claw” charge connection. When I first got the truck, I really didn’t know what to expect for charging on it. I knew that the GM EV-1 and the Chevy S10 Electric both used inductive paddle chargers. The Ford’s AVCON was new to me. I did some research and quickly found that it was just an early version of J1772 – the standard that all electric cars in the U.S. use today! Because of that, it would use the same signaling system. In theory, it would be EASY to build an adapter!
Using parts I already had, I threw together an adapter. I previously salvaged a J1772 inlet from a flood damaged Mitsubishi iMiEV. I used that to build an adapter for charging my electric motorcycle from public EV Charging Stations. Taking that old project apart provided me with the inlet I needed to build the adapter for the truck.
On the other end, I’d need an AVCON connector. When I got the truck, it included a bulky and heavy “Charging Post” EVSE with one AVCON cable on it. The post looked like it was originally designed to hold two cables. Separate from that was another cable, going into a generic circuit breaker box. I think somebody was trying to build a “portable” EVSE, but didn’t know about the proximity and pilot signals that are also involved with such a thing. I pulled the cable off this box to build my adapter.
I double-checked the circuit diagram on Wikipedia to make sure I had the pins right. The heavy duty pins on the J1772 inlet are pretty obvious – two current-carrying “hot” wires, and a ground wire. The two smaller pins are Pilot and Proximity. The proximity connection is mostly to keep a person from starting and driving off in an electric vehicle while they are still plugged in.
In the Ford Ranger EV, the earlier style connection did NOT have a conductive pin for checking proximity. Instead, there is a magnet right in the male connector. In the female port of the truck is a magnetically activated switch. When the cable is plugged-in, the magnet activates the switch and signals to the truck, preventing it from being turned on or driven. Since this system is already in the truck and AVCON connection, I did NOT have to do anything with the proximity pin in the J1772 inlet.
“Pilot” is the signal that communicates between the Electric Vehicle Supply Equipment (EVSE, sometimes just called a charging cord.) Because the truck used an earlier version (ASE J1772-2001) of the same protocol we use now (ASE J1772-2009) all I needed to do was simply connect together the wire from the inlet to the matching wire on the AVCON cable!
The pilot signal communicates between the vehicle and the EVSE. With it, the vehicle is able to determine the maximum available charging current, and then charge based on what’s available. This prevents cars with high-power chargers from melting wires or blowing fuses on lower power charging stations.
With the inlet and AVCON claw connector cable, all I needed to do was use wire nuts to match each wire up with it’s mate and make a secure electrical connection. This is just temporary, as I’m simply testing if it works at all! The inlet I have is only rated for 20A. The truck can draw more than that, so I’ll want to get an inlet with a higher current rating before finishing the project and properly closing it all up.
I tested the adapter and…. It worked great!
I tested it with both a 16A and 32A EVSE and monitored the current draw. Sure enough, the truck drew no more than what was appropriate depending on the EVSE.
By completing this project, I’ll be able to drive this truck in public and charge at ANY modern electric car charging station!
If you want more details on J1772 protocols, start with the Wikipedia entry page. It’s interesting stuff and not too terribly complicated.
Until next time, stay charged up!
-Ben Nelson
PS: Why did I actually do this? I could have removed the truck’s charge port and installed a J1772-2009 connection there, but that would have been modifying a CLASSIC Electric Vehicle! I also got an AVCON EVSE with the truck, but it’s HUGE and clunky. It’s kind of a pain to use to charge the truck. Much easier just to use the EVSE I already have and use every day for charging my car!