Switching Charging Current

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Papageno

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Joined
Feb 9, 2019
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I recently had a 240V charging station installed, but I cannot switch the charging level in my 2014 I3 from 120V to 240V. I followed the instructions but still no go. Did anyone encounter the same problem?

Thanks in advance
 
Can you give more details on what is happening?
Screen should show:
Level 1 Charging (120v)
Level 2 Charging (240v)

You should be able to set reduced or max for each level.

The car recognizes which cable you plug in, 120v or 240v, and then charges accordingly.
A 120 volt cable has one 120v hot wire, one neutral wire, and one ground wire. A 240 volt cable has two 120v hot wires, and one ground wire.

What happens when you plug in the 240 volt charging cable? What color lights at the charge port?
What brand charging station? What settings does it have?
 
The car should just automatically charge, assuming that the EVSE is good and wired properly. It doesn't care which input or how big it is...the two communicate so that the car doesn't try to draw more than the device can provide.

As said, you can tell the car to limit the maximum it will use, but the only time that is really useful is if the EVSE shares the supply with something else, and using the full amount would overload the supply to it.

The pilot signal from the EVSE indicates how much power is available, and the i3 adjusts its draw from it so it doesn't exceed that.
 
If it's charging, it's using the voltage you're supplying.

Note that at least in the US, there are two different ways to wire up 240V. One way is to have a full 240V over a single wire (with a return wire coming back.) The other major method is where there are two separate 120V feeds on two separate wires (plus a return wire.). If yours is the two separate 120V feeds combining to 240V in the connector, it's possible that one of the 120V feeds is bad. Note that this is rather unusual unless you have an old house that has never had its electricity updated. (pre-1960s, that still has fuses rather than breakers.)
 
Papageno said:
I recently had a 240V charging station installed, but I cannot switch the charging level in my 2014 I3 from 120V to 240V. I followed the instructions but still no go. Did anyone encounter the same problem?
If your car still charges using the one that came with it, then the problem is probably in the new charger. We can do couple of simple tests to find out IF you have a volt-ohm meter. If you don't, Harbor Freight sells cheap but good enough ones for ~$5 and Walmart is close behind.

Looking head-on at the J1772 plug, you see five pins:
J1772_120.jpg

  • top two pins - these are the power lines that have NO power until the charger and car 'negotiate'. We won't be testing these lines.
  • bottom pin - the ground is the reference we will use for measuring the control lines, presence and pilot.
  • left pin - this is the 'presence' line that is a resistor operated by the latch. We will measure the resistance between ground and the 'presence' pin to make sure the resistor and the switch operated latch work.
  • right pin - the pilot signal should have +12V relative to the ground. A -12V means the charger has a problem and won't work. Now to do more pilot signal testing requires having a resistor network between the pilot line and the ground. We won't do that because you would need test equipment more complex than a volt-ohm meter. Also, this would risk enabling the two power pins and that would be too exciting.

Perhaps you might share some photos of the charger, its power connection, and what happens to the lights around the charging port when it is plugged-in. Use the charger that came with the car to see the proper light sequence.

Bob Wilson
 
You might also check the simplest first - that the double-pole breaker in your electrical panel for the new 240 v charger is actually in the "on" position, and whatever indicator light on your new charge station is showing power to it,
 
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