EMW Juice Box

Sogorman · Jan 21, 2014

Just wanted to let any potential buyers know that I have a Juice Box on order which should arrive in 2-3 weeks. I choose the juice box because of it's low cost for a 6kw L2 charger but more over it will allow me to bump up my L1 charging which I am stuck with until we move in two or three months. For what it's worth the ford limits L1 charging at around 11.5 amps which is just below 80% load on a 15 amp circuit. I will be servicing the Juice Box with a 20 amp 120 v circuit and with it's open source firmware I will be able to charge at 16 amps, almost a 40% increase in current.

I'll let you know once I have it installed and up and running

Sean

sefs · Jan 21, 2014

Unfortunately, the FFE limits itself to 12A on 120V. I tried with a 16A pilot signal there was only 0.5A difference. On a 12A pilot signal 120V it pulled about 11.5A, and on a 16A pilot signal 120V it only pulled 12A. :|

Sogorman · Jan 21, 2014

Well there goes that idea. I get the 11.5A limit on the stock charger but it would be nice for the car to respond to the 16A signal so you could get a decent charge rate on a 20A circuit.

Out of curiosity do you have a EMW charger or did you build something into a different J1772 connector to adjust the pilot signal?

Astrand1 · Jan 21, 2014

Yeah it would be cool if we could just dial in the amperage upto the limit of the charger right on the MFT like you can do on a Model S. But I'm sure it's all about "CYA" with Ford. They don't want some ******* to burn their house down trying to pull to much from a wall outlet.

sefs · Jan 21, 2014

Sogorman said:
Well there goes that idea. I get the 11.5A limit on the stock charger but it would be nice for the car to respond to the 16A signal so you could get a decent charge rate on a 20A circuit.

Out of curiosity do you have a EMW charger or did you build something into a different J1772 connector to adjust the pilot signal?

I have a Tesla Model S UMC converted to J1772. The UMC has a NEMA 5-20 plug adapter that makes the UMC send a 16A pilot signal. Interestingly enough, the pilot signal doesn't say anything about the voltage. It just tells the car the current limitation. The car measures the incoming voltage. The Tesla UMC can work on 120V or 240V. So, I have an adapter that will take a NEMA 6-20 outlet and allow me to plug in my NEMA 5-20 adapter (I only know this to work with the Tesla UMC, don't make this adapter and try it with the Ford 120V EVSE or some other Level I EVSE). Anyhow, using this adapter, the FFE will pull 16A at 240V; so I know the pilot signal is working correctly. I wish it would pull 16A at 120V, as there are quite a few places that have NEMA 5-20 outlets, but there is some limitation in the FFE that prevents this.