208 vs. 240 V

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Fabio

Well-known member
Joined
Sep 4, 2010
Messages
278
I've received the AV charger and I see this jumper to set 208 V input.
What difference does it actually make? Can one unit still function if one were (hypothetically speaking) to cut that jumper and connect to a regular 240 @ 30A circuit?
 
I would move the jumper to the position that corrosponds to your situation.
208 is usually two legs of three phase power, 240 is normal single phase power.
 
Read the EVSE manual provided with your AV unit. Page 71 shows that you need to CUT the jumper IF the supply voltage is 208 Volts. Otherwise, leave the jumper alone.
 
You almost certainly won't have 208v. As smkettner said, 208v is generally two legs of commercial three phase power. I understand it may be possible to find three phase power in a real old home, but you're unlikely to find it in a modern or semi-modern home.
 
Obviously what Fabio was thinking was that 208v 40A might be equivalent to 240v 30A, so cutting the wire might let him use the unit on a 30A circuit. I'm no EE, but I expect it is the amps, not the watts, that matters here.
 
Nope, while my University Professor may disagree about my understanding of Analog Electrical circuits , I was under no illusion of that :)
it's just that my electrician cut the breaker without thinking and I need to decide if I need it replaced or solder the jumper back or ignore it (the self test is OK)


planet4ever said:
Obviously what Fabio was thinking was that 208v 40A might be equivalent to 240v 30A, so cutting the wire might let him use the unit on a 30A circuit. I'm no EE, but I expect it is the amps, not the watts, that matters here.
 
I suspect that Nissan is requiring 240V 40A circuits in preparation for a future increase from the 3.3kW to a 6.6kW charging unit in the car. Although 3.3 only converts to 13.75A at 240V and 6.6 to 27.5A, I suspect that they wanted a little more cushion and went with the 40A circuit. Another interesting item is that when one installs a 40A circuit the next common wire size to accommodate that is #8 wire. #8 wire can take as much as 55A so they have really covered their bases with extra capacity/safety.
 
It is a "jumper" wire, not a "breaker", but ...
best to call AV Technical Support and ask them what difference the jumper makes.

Possibly just changes a power calculation that we do not even see. Possibly changes the generation of the +/- 12v for the circuit board.

If running on 240v, it SHOULD be re-connected, or they would not have needed the jumper, right?

If re-connecting, REMOVE ALL POWER ... FIRST.
 
By Electrical Code:
A device capable of supporting a "continuous" load OVER 24 amps and as high as 32 amps requires a 40-amp breaker and circuit.

The 30-amp breaker handles OVER 16 and as high as 24 amps.

So, the AV unit is configured to "offer" the EV (up to) 30 amps, and even though the first LEAFs only use 15 or 16 (we think), the "30-amp" AV EVSE requires a 40-amp breaker.

AV could easily make a 16-amp version that requires only a 20-amp breaker. Or, a 24-amp version that would use a 30-amp breaker. Ask the AV Technical Support if they can supply (or modify) a unit for your needs.

The upcoming SPX unit (according to their literature) can be set, in the field, to match your breaker. :D
 
Thanks for the correction, that's what I happens when I type while watching Soccer...
I think too that I will solder the jumper wire back, to be on the safe side.

garygid said:
It is a "jumper" wire, not a "breaker", but ...
best to call AV Technical Support and ask them what difference the jumper makes.

Possibly just changes a power calculation that we do not even see. Possibly changes the generation of the +/- 12v for the circuit board.

If running on 240v, it SHOULD be re-connected, or they would not have needed the jumper, right?

If re-connecting, REMOVE ALL POWER ... FIRST.
 
Fabio said:
it's just that my electrician cut the breaker without thinking and I need to decide if I need it replaced or solder the jumper back or ignore it (the self test is OK)
Measure the voltage. Read the manual. Adjust the jumper if needed so that it is correct.
 
I also notice on the Japan website, they refer to the infamous cold weather package

It includes a "PTC" (pack temp control) listed as 5kw

I think this system operates when plugged in only , if so it would need a 240v 40a circuit breaker

weather or not the charger is upgraded to 6.6kw
 
If anyone is interested in the actual purpose of the jumper ...
I just spoken with an AeroVironment technician who told me that the purpose of that jumper is for a daughter board that they plan to add in the future to measure consumption. For the model sold today, that jumper serves no purpose whatsoever.
Thanks to all the replies, I know you guys were well intentioned. :)
 
Back
Top