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[GoneToPlaid]

I just mounted four Diginow SCv2 chargers on my DSR, and rode over to the electric co-op office to test with their Chargepoint EVSE.  I had trouble activating both plugs at once.  I used my phone and NFC to authenticate, which would unlatch the plugs.  The first one I plugged in to my chargers worked, but the second one would not.  Scanning my phone again would not let me use the other plug.  Eventually I made a second Chargepoint account, and used it to authenticate and was then able to use the second plug.

Is there an easier way to use dual J1772 plugs with a Chargepoint station? Searching this forum and the web has not turned up anything for me so far.

I mounted two chargers per side, in little aluminum side boxes.  It's not done yet, but ready enough for testing.

[Crissa]

How dare you try to give them twice as much money!

Tho it probably saves them all the people who swap from one side to the other being double charged...

-Crissa

[GoneToPlaid]

Right, or the wrong person being charged somehow.  Mostly I think they just don't expect this use case.  This particular charger is free, though .

I think Chargepoint also will issue a payment card.  So I may get two cards, for two accounts, and just keep them in the tank bag.  That would be a lot faster than logging out of one account and into the other.

[StableofZeros]

I’ve done this Several times, you have to either call ChargePoint and ask them to activate a second charger on your account, or get the payment card and swipe it at the second station. You can’t activate two stations from your phone at once.

[Crissa]

Ruins someone paying for someone else's charge, I suppose.  Like caravanning during a move.

-Crissa

[StableofZeros]

They made it seem like I could make one phone call to their support line and they’d activate however many you want!

[MVetter]

Use the app to start one. Tap your phone to start the other one. Or order an RFID card for $5.

I’ve done this Several times, you have to either call ChargePoint and ask them to activate a second charger on your account, or get the payment card and swipe it at the second station. You can’t activate two stations from your phone at once.

You absolutely can. Just in two different ways.

[DonTom]

I have several CharePoint cards. I never pay any attention to which one I use at a 2nd machine. I have charged my SR at 8KW several times and Chargepoints can usually only do around 6.6 each IIRC so I often hog up two stations.

FWIW, I wish they would get rid of all those J1772's and simply replace them all with a 14-50R's. And then we can get 12KW out of a single outlet. Same with Tesla Destination chargers.

BTW, can somebody here explain why a pilot signal is necessary for any vehicle?  It often causes problems for nothing, IMO.

I can charge all four of my EVs direct from 14-50R, so why all the unnecessary BS in J1772 and TD stations? It's all just 240 VAC, but the 14-50R is usually 12KW capable.

-Don-  Reno, NV

[Crissa]

I'm sure they limit the output for the same reason they don't just leave out a 50a outlet.  The pilot signal is to tell the charging vehicle how much it can draw.  And not every circuit is okay with a 50a draw.

-Crissa

[DonTom]

I'm sure they limit the output for the same reason they don't just leave out a 50a outlet.  The pilot signal is to tell the charging vehicle how much it can draw.  And not every circuit is okay with a 50a draw.
-Crissa

It doesn't work that way. If your EV charger draws ten amps at 240 VAC, it will draw ten amps even with a source capable of  a billion amps.  That is why I asked. 

240 VAC times ten amp draw =2,400 watts.

If you have a supply capable of a billion amps, the math  is the same, it's still a ten amp draw from that billion amp supply and you still have 2,400 watts.

I assume the pilot has something to do with safety and is unnecessary overkill.

I see no reason to NOT use a 14-50R for all EV charging. I think part of the fear is some people won't understand what happens if they get their fingers in the plug somehow. I know J-1772 is off until it is connected, unlike a 14-50R which is always hot and dangerous around idiots.

I just now looked it up here. It looks like the so called pilot in J-1772 is just the diode and the resistor and is only there  for safety reasons. Must be the same on the Tesla Destination stations  and what will also explain why some vehicles do not like the regular Tesla-Tap. It's because you have the diode and resistor then in parallel. One time to activate the J-1772 and another one to active the Tesla station. But now they are both in parallel and about half (diodes are tricky here)  the total resistance.

And that 100% explains why they sell this box. It's not to be used with a J-1772. That would defeat its entire purpose.

BTW, I opened mine to see what is inside. NOTING except the wires. But the diode and resistor is part of the Tesla inlet that I cannot see. No diode, no resistor that I can see, but I do see it on the small pins with an ohmmeter.  That explains how it works. Then when plugged into with  Tesla Destination station it  then only see the ONE "pilot" it expects to see and NOT  the one from the J-1772 because there is no J-1172 when this box is used.

So that explains it all. And I still say the plain 14-50R is better, just not as idiot-proofed.

-Don-  Reno, NV

[Crissa]

I'm sure they limit the output for the same reason they don't just leave out a 50a outlet.  The pilot signal is to tell the charging vehicle how much it can draw.  And not every circuit is okay with a 50a draw.

It doesn't work that way. If your EV charger draws ten amps at 240 VAC, it will draw ten amps even with a source capable of  a billion amps.  That is why I asked. 

It does work that way.  If your charger is capable of 12, and the EVSE is only capable of 3, the pilot signal tells your charger not to exceed 3.  That is the entire purpose of an EVSE, to electrically communicate the capacity of the outlet.

And that 100% explains why they sell this box. It's not to be used with a J-1772. That would defeat its entire purpose.

That device might be handy, but it defeats the safety.  If you draw 12 through it and the EVSE was only capable of 7, you will set the EVSE's circuit on fire.  An electrician or inspector would be very cross with your installation.

-Crissa

[DonTom]

It does work that way.  If your charger is capable of 12, and the EVSE is only capable of 3, the pilot signal tells your charger not to exceed 3.  That is the entire purpose of an EVSE, to electrically communicate the capacity of the outlet.

Ever see a 14-50R that was only capable of three KWs?  Now you see what I mean? We do not have to tell the 14-50R anything at all. We only have to tell the J-1772. The problem is caused by its own stupid design (IMO) of the J-1772.

That device might be handy, but it defeats the safety.  If you draw 12 through it and the EVSE was only capable of 7, you will set the EVSE's circuit on fire.  An electrician or inspector would be very cross with your installation.

Nope, that is not a real issue, That is why the charge stations all have circuit breakers (and yes, I have tripped a couple  with my 7.9 KWs from a single station). But a plain 14-50R can handle the entire 50 amps at 240 VAC, at least in most cases, before the CB will trip. Usually  60 amp CBs are used with home 12 KW Telsa Destination stations  as they follow the 80% rule. That is 48 amps. That is what I have at my houses.

That is as good as a 14-50R. And a few Tesla Destination stations are 16KW (66 amps). Even better than the 14-50R.

The big limitations are on the J-1772, Probably is for safety, but it's the exact same issue with anybody who has a 14-50R in their garage and many do.  So why not get rid of the J-1772 and replace them all with a 14-50R that everybody can use at any current draw needed?  Why should an inspector pass a house with a 14-50R but not out on the road?  Makes no sense to me.

-Don- Reno, NV

[Crissa]

Ever see a 14-50R that was only capable of three KWs?

No.  Because that would violate the electrical code.

On the other hand, you can have EVSEs on all sorts of circuits.  And that pilot signal tells the EV what it's plugged into.

Your little device defeats those safety measures.

-Crissa

[DonTom]

Ever see a 14-50R that was only capable of three KWs?

No.  Because that would violate the electrical code.

On the other hand, you can have EVSEs on all sorts of circuits.  And that pilot signal tells the EV what it's plugged into.

Your little device defeats those safety measures.

-Crissa

On J-1772, it is just a diode and a resistor that tells the station to turn on. Nothing complicated about it. Either you get 240 VAC or you don't. Nothing to adjust the voltage to change the current draw.

On DC charging, it can get quite complicated. The chargers are real chargers and run a fancy program. That is where they need the signals to tell the true DC charger what voltage and current your EV can handle. My Energica will be perhaps 25 KW. The next person to plug in could get 150 KW from the same charger, as well as at a much different voltage. And even adjusts by battery temperature as well as SOC and everything else possible.  I don't claim to know fully how DC charging works. But I do know it is nothing like a J-1772.

But J1772's are NOT chargers at all. They are much like a 240 VAC outlet in your house. No way to control it other than off and on.

IMO, J1772, even though very simple,  has a lot of unnecessary BS at the high price of current availability.

With DC charging the complexity is necessary. But not with AC. Just give me a 14-50R and let me charge at my full 8KW, please. You can have all the J-1772 stations that can only do 6.6 KW or whatever.

If all Tesla destination stations as well as all J-1772's were replaced with a simple 14-50R, I could always charge at the max and not have to carry nearly as many adapters.

I hope somebody here can explain the big advantage with J-1772 over a simple 14-50R. I only see the disadvantages and there are many.

At least the Tesla Destination stations can often do 12 KW or better, unlike the J-1772.

-Don-  Reno, NV

[DonTom]

Your little device defeats those safety measures.

-Crissa

One safety measure of J-1772 is that it is expected that many cars will charge outdoors in the rain. A lot of the safety features of J-1772 is about that possibility.

But all they really need there is GFI. And the same GFI can be on a 14-50R.

-Don-  Reno, NV