Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

HEADS-UP: Simultaneously Charging a Tesla and a LEAF

This site may earn commission on affiliate links.
William3 said ... (in a thread about "stock rims for sale"):
I was cleaning out the garage (to make room for the Nissan Leaf) and realized that I still have these rims.

From a LEAF Forum (7th post on page 1)

Bottom Line: Do *NOT* charge a LEAF and a Tesla at the same time.

Further info from the grapevine:

Further digging ... it appears the on-board charger in the LEAF causes a substantial amount of noise on the circuit and house panel, which also feeds into the Roadster's PEM causing a "bug-zapper" type of noise :cursing:

And apparently Nissan is working on the issue. And might have a noise-filter solution within a few weeks.

It seems prudent to
a. pay attention to the Tesla PEM if the Roadster is plugged in and charging when you plug in your LEAF for charging at 240V; the above referenced link speaks of 2008, or 1.5 Roadster, and it is unknown whether the (significantly different) 2.0 PEM has the same symptom;
b. avoid simultaneous charging until the LEAF is "fixed".
c. Even if no apparent "noise" is noticed in 2.0 Roadster ... I'd be cautious.
d. Even with LEAF 120V charging ... I'd be cautious.

Just a heads-up ... :smile:
 
Do any of the EVSE's provide line noise filtering on the 240V? I wonder if this issue could be more or less pronounced depending on what J1772 EVSE you use to plug in the Leaf.
 
Do any of the EVSE's provide line noise filtering on the 240V? I wonder if this issue could be more or less pronounced depending on what J1772 EVSE you use to plug in the Leaf.
A regular EVSE (the ones at residences and "resonably" priced) definitely do not contain noise filtering of the power lines (in or out) ... there's simply a relay or a contactor between the car and the breaker. Although there may be more complex things going on (from an analog circuit perspective) causing some variation, my hunch is that the EVSE model won't make any significant difference.
 
My car is a 2010 Roadster #8xx
My Roadster charger is the 70amp HPC.
My Leaf charger is the one that Nissan is pushing (made by AV).
I barely find time to keep up with THIS forum, so I don't really bother with the Leaf forum. If you guys that read it discover anything else that I should know please pass it along. Thanks!
2010 Roadsters might be ok because the PEM is so significantly different. But that's not really the point, because if the LEAF causes such problems on a 2008 Roadster, PV inverters, GFCI's, other electronic equipment in the house (according to the LEAF forum posts), then there's something that needs to be fixed on the LEAF. Of course, not all LEAFs might be "bad", but it sounds like it's not an isolated case.

Open the trunk of the 2010 Roadster and wait for the normal noises (pumps, fans) to stabilize and to "learn" them. Then plug in the Roadster and start charging, all the while carefully again "learning" the normal noises, this time specifically from the PEM. Now have a helper plug in the LEAF and listen carefully what happens at the PEM of the Roadster when the LEAF starts charging. Try at least 24A and 40A and 70A on the roadster, although my guess is ... it won't make a difference.

You may not be able to hear any effect/noise-diference when the LEAF charges, which would be good.

Another test to see if your LEAF is "bad": invite over a 2008 Roadster owner. :)
 
I have PV inverters right next to my Leaf EVSE. So far (knock on wood), I haven't heard any unusual noises from the inverters or anything else in the house while the Leaf charges.
Maybe I got a "good" charger in the Leaf, or maybe something else about the house wiring is a contributing factor.
(As usual, grounding paths are a topic of discussion.)
 
Further digging ... it appears the on-board charger in the LEAF causes a substantial amount of noise on the circuit and house panel, which also feeds into the Roadster's PEM causing a "bug-zapper" type of noise
I've heard the 60Hz "bug-zapper" at home on clean (evening) power charging my 1.5, so I don't think it is a leaf thing...

It seems prudent to
a. pay attention to the Tesla PEM if the Roadster is plugged in and charging when you plug in your LEAF for charging at 240V; the above referenced link speaks of 2008, or 1.5 Roadster, and it is unknown whether the (significantly different) 2.0 PEM has the same symptom;
b. avoid simultaneous charging until the LEAF is "fixed".
c. Even if no apparent "noise" is noticed in 2.0 Roadster ... I'd be cautious.
d. Even with LEAF 120V charging ... I'd be cautious.

I just experienced this problem. I have been charging on a 208V nema 14-30 outlet at work for a couple of months. Last Friday a new leaf parked in the spot next to mine and plugged into the 120V outlet. Within a few hours, the GFI breaker on my outlet tripped. The same thing happend today (Tuesday). A few hours later I was able to reset the breaker and finish charging. It seems that the leaf can trip my breaker when it is drawing max current, but doesn't seem to trip it when it's near the end of it's (the leaf's) charge.

I worked with the electrician when the outlet was installed and we upgraded to #8 wire... So I know the wiring is good. When this happened, I double checked it again.

The power comes from a 3 phase breaker. My outlet is on the B & C phases. The 120V outlets are on the B & C phases too and share a common neutral (allowed for 3 phase systems). We plan to move one of the outlets to the A phase in an attempt to keep the Leaf's dirty power off the B&C phases. I will also try and measure the power factor of the leaf charger.
 
Last edited:
I worked with the electrician when the outlet was installed and we upgraded to #8 wire... So I know the wiring is good. When this happened, I double checked it again.
I didn't know any better, and installed #4 wire (four separate 70 A wires) with my NEMA 14-50R, and I also used a 60 A breaker. I'm planning on "downgrading" to 55 A wire and a 50 A breaker, now that I realize the Roadster really only pulls 40 A on the NEMA 14-50. After reading this thread, I wonder if I should expect problems to appear?
 
...so a Leaf moves in, and there goes the neighbourhood?...:confused::wink::biggrin:


I've heard the 60Hz "bug-zapper" at home on clean (evening) power charging my 1.5, so I don't think it is a leaf thing...



I just experienced this problem. I have been charging on a 208V nema 14-30 outlet at work for a couple of months. Last Friday a new leaf parked in the spot next to mine and plugged into the 120V outlet. Within a few hours, the GFI breaker on my outlet tripped. The same thing happend today (Tuesday). A few hours later I was able to reset the breaker and finish charging. It seems that the leaf can trip my breaker when it is drawing max current, but doesn't seem to trip it when it's near the end of it's (the leaf's) charge.

I worked with the electrician when the outlet was installed and we upgraded to #8 wire... So I know the wiring is good. When this happened, I double checked it again.

The power comes from a 3 phase breaker. My outlet is on the B & C phases. The 120V outlets are on the B & C phases too and share a common neutral (allowed for 3 phase systems). We plan to move one of the outlets to the A phase in an attempt to keep the Leaf's dirty power off the B&C phases. I will also try and measure the power factor of the leaf charger.
 
I've heard the 60Hz "bug-zapper" at home on clean (evening) power charging my 1.5, so I don't think it is a leaf thing...

if I remember correctly range-meister Eberhard mentioned in a different thread, that Tesla licensed the charger from A.C. Propulsion for the first 500 Roadsters.
In the this charger the winding of the stator is used for charging ( as a choke ? ) So it would be normal to hear this noise, it is generated by the micro movement of the wires,which are pushed and pulled with 60 Hz. When the motor rotates you won't hear this due to the louder bearing + fan noise.
 
you need a 50 amp breaker as the recipticle will only take 50 amps.
Good advice! I didn't think about that. Easy to change since I've already purchased the 50A breaker.

If you upgrade later to an HPC or other reciptacle then the wires will be in place.
I disagree on this one. The HPC wires directly in without a receptacle, and I would need a new conduit for the HPC anyway. I'm planning on taking out the 70A wire just because it's so thick that it's in the way. Things will fit much nicer with the 55A wire, and I've already purchased it. The 70A wire wouldn't be good enough for the HPC anyway, since I'd need 90A wire for that. 70A (or 72A?) is the load on the 90A breaker.
 
If anyone cares, I did downgrade to a 50 A breaker and 55 A wire. I though the smaller gauge wire would be easier to work with than the 70 A, but it was still a pain!

P.S. I verified that the neutral wire is not used by the Tesla UMC, but the Safety Ground is most certainly connected. I still wired the neutral to my house in case I ever plug anything else in to that receptacle.
 
Any updates on this issue of charging both cars at the same time?
Yes ... Nissan determined that better filtering is in order and started updating the charger in the LEAF. However, I am not privy to details (like starting with which VIN). A particular LEAF owner who also happens to charge where a Tesla Roadster 1.5 charges at the same location has had the LEAF updated via a warranty service at the Nissan dealer. That solved the issue.

My guess: LEAF VINs after probably 2,000 should be ok, but no guarantees. If you have a 1.5 Roadster charging off the same electrical service (sometimes hard to determine -- separated circuits are *NOT* sufficient isolation) as an early (<2000 VIN) LEAF ... I would pay close attention if it is unavoidable to charge simultaneosly. Again, the VIN cut off is a (conservative) guess ... I don't know if Nissan can be prodded to release that info. And then there's the uncertainty of older VINs getting updated.

Some folks I've talked to think this issue is being overblown. Ok ... but if it was my $100k car ... I'd want to be very conservative.
 
Now I'm more glad than ever that Nissan botched my order so that I was unable to get a Leaf. And especially glad that I didn't get a Volt, which I would have done had it been available two years ago. I guess GM has a new strategy for trying to kill EVs. :scared:
 
My guess: LEAF VINs after probably 2,000 should be ok, but no guarantees. If you have a 1.5 Roadster charging off the same electrical service (sometimes hard to determine -- separated circuits are *NOT* sufficient isolation) as an early (<2000 VIN) LEAF ... I would pay close attention if it is unavoidable to charge simultaneosly. Again, the VIN cut off is a (conservative) guess ... I don't know if Nissan can be prodded to release that info. And then there's the uncertainty of older VINs getting updated.
Nissan does have a line filter installed right before the actual charger unit in the vehicle. I have VIN 568 and have no measurable line noise and have never tripped a GFCI. One thing I have noticed is that some owners that have reported random issues have also report low line voltage. One LEAF owner also has reported that the car will attempt to draw more amperage in the event of a voltage sag. I'm not sure if that could be related, but my home runs just above nominal voltage (244/122 volts to the outlets).
 
Nissan does have a line filter installed right before the actual charger unit in the vehicle. I have VIN 568 and have no measurable line noise and have never tripped a GFCI. One thing I have noticed is that some owners that have reported random issues have also report low line voltage. One LEAF owner also has reported that the car will attempt to draw more amperage in the event of a voltage sag. I'm not sure if that could be related, but my home runs just above nominal voltage (244/122 volts to the outlets).

Wow, is that ever brilliant (I'm being sarcastic in case you didn't guess)? The circuit is already overloaded, so you try to load it more.