Power Xpress problems

Power Xpress problems

I bought a Power Xpress charger as a back-up for my mobile connector. It refuses to charge my Model S. It does however charge my friends Volt. I even lowered the amperage to 5 amps and it still will not charge. I know my adapter is working, I charged on another friends J1772. Any one else try to charge with a Power Xpress charger?

ViewAskew | 30 January 2013

I actually recieved a PWR XPRS charger from my local electric company. (part of their EV install program) It charged my S the first day I tried it. After that it faults out and I get a solid red light. I've done all their reset trick but nothing helps. They are suppose to send me another unit soon. I'd be curious if it would charged another vehicle. (i.e. a Volt)

chadrchristensen79 | 30 January 2013

I thought that the model s charger
was integrated into the car , so there
Is no need for a separate charger.

jat | 30 January 2013

@chadrchristensen79 - the terminology is somewhat confusing. The Mobile Connector, Aerovironment charging dock, HPWC, Power Xpress, etc are all technically EVSE (Electric Vehicle Supply Equipment). They don't do much except provide for ground fault isolation and communicate with the car about what voltage/current is available, and then supplying what is requested.

The AC chargers are actually in the car, and rectify AC to DC to charge the battery. There is also monitoring of the charging process and communicating with the EVSE.

In the case of fast DC charging (such as Tesla Superchargers or CHAdeMO), the EVSE still communicates with the car to negotiate what can be supplied vs. what is desired, but the rectifiers in the car aren't involved at all -- the supplied DC goes straight to the battery.

DouglasR | 30 January 2013

Wouldn't the ESVE provided by Aerovironment, Blink, ChargePoint, etc. also function as chargers, i.e., rectifiers, at least with cars other than the Tesla? It was my understanding that the Leaf, Volt, and other plug-ins do not have built-in chargers, yet they use these stations. Is that incorrect?

djp | 30 January 2013

The LEAF charger is in the car. The station just provides 240vpower

diegoPasadena | 30 January 2013
So what is the benefit of such a Power Xpress charger over just plugging it into a NEMA 14-50 socket?

nwdiver93 | 30 January 2013

Sorry... I did mean "connector" not charger.

Please post if your problem is resolved. It sounds exactly like my problem. Everything initially looks fine ~240vac then the voltage cycles quickly 0-240 a couple times then the car gives up and says "no wall power". The Volt does something similar and also says "no wall power" at some point but it doesn't give up like the Tesla and eventually starts charging.

nickjhowe | 30 January 2013

@diegoPasadena - a quick glance at the Power Xpress specs makes it look worse than NEMA 14-50 - 32A instead of 40A. I guess if you need J1772 for some other reason it makes sense, but at first glance for Model S it looks like a bad idea.

jat | 30 January 2013

@DouglasR - no, any car with J1772 will have the rectifier in the car.

@diegoPasadena - You can plug the J1772 plug directly into the car (with the adapter). The NEMA 14-50 socket still requires an EVSE, in this case the Tesla Mobile Connector.

I agree with @nickjhowe - the only reason the get a J1772 EVSE for the Model S is if you also have another EV you want to share it with, but it will almost certainly be worth having separate charging spots in that case.

ViewAskew | 31 January 2013

@nwdiver93 - As soon as I recieve the replacement unit I'll post and let everyone know.

As far as my reason for using the charger, it's not because I want to. Long story short... When I ordered my S I requested the 14-50 adapter because it's more common. I assumed when my pwr company came and installed my 240v line it would have 14-50 socket. They ended up giving me a 6-50 socket. So I just ordered an adapter from Tesla so I can use the Model S cable. I was using the PWR EXPRS until it arrived.