Electrical line noise while charging at 240V

[Ingineer]

As I mentioned before, I don't believe this has anything to do with the EVSE. If you are hearing direct audible noise from your panel/subpanel this does not sound good! Usually noise indicates arcing, which would definitely cause plenty of EMI/RFI using the AC wiring as an antenna.

I will volunteer to stop by your place next time I'm in the southbay and check it out if you have not found the source of the problem by then. Are you available anytime during the day on weekdays, maybe at lunchtime?

If you are comfortable with it, I recommend you open your panel and start charging on 240v to see if you can locate the source of the noise. In particular, look for any screws or terminals that are discolored.

I have a thermal imaging camera that will spot such things quickly.

Until you can figure out what's happening, I agree with your recommendation to stop charging on 240v until you can isolate the cause.

-Phil

 

[garygid]

The symptom at the "hill" residence was not 60Hz noise, but a high-frequency (over about 3kHz) static-type noise (while charging through his AV EVSE) that I cannot hear with my old ears.

A quiet 120Hz hum is normal within a foot or two of SMA (SunnyBoy) inverters.

We should probably just wait for the "week or so".

 

[GeekEV]

We should probably just wait for the "week or so".

While it can be fun to troubleshoot, I agree - I'm sure Nissan will make good. And I can't imagine any of us have more resources than they do... :shock:

 

[tbleakne]

The fact you audibly hear the noise at the sub-panel is stunning.
With really high levels of radio frequency, such as at the transmitter of a very high power radio station, it is possible to hear the song that is playing audibly at the power connections. But that is at a staggering level of radio frequency energy.

This is a different effect. A RF wave with AM modulation only generates audio-frequency components when it is rectified, which requires non-linearity. A good electrical panel is highly linear, but some bad connections can introduce very slight non-linearities. This, combined with a very powerful, local signal can produce weak electrical components that match the audio modulation frequencies.

If you are hearing direct audible noise from your panel/subpanel this does not sound good! Usually noise indicates arcing, which would definitely cause plenty of EMI/RFI using the AC wiring as an antenna.
-Phil

I agree arcing would be dangerous, but I don't believe that is causing the sound here.

A wire pair carrying current with significant audio-frequency components can vibrate at the same frequencies due to the magnetic forces between conductors. I would call this loose wiring, not loose connections, so it would not be dangerous. If the wiring is free to vibrate mechanically, this can cause sound. Higher frequencies will radiate sound better. Of course an audio speaker can do this much more efficiently.

I agree the noise is originating in the charger, not the EVSE, but different EVSE models will have different amounts of filtering. The very fact that we call it RFI (radio-frequency interference) filtering suggests that it is not tuned to audio frequencies, as mogur has suggested.

The charger in the car most likely chops the incoming 60 Hz power into a higher frequency that facilitates rectifying and transforming the power to the voltage required by the battery. Such switching power supplies introduce lots of harmonics, multiples of the fundamental chopping frequency, but I would expect all these frequencies to be above the audio range. However, imbalances in the switching circuitry could introduce sub-harmonics in the audio range. Perhaps this is what folks are hearing.

 

[Ingineer]

I agree arcing would be dangerous, but I don't believe that is causing the sound here.

A wire pair carrying current with significant audio-frequency components can vibrate at the same frequencies due to the magnetic forces between conductors. I would call this loose wiring, not loose connections, so it would not be dangerous. If the wiring is free to vibrate mechanically, this can cause sound. Higher frequencies will radiate sound better. Of course an audio speaker can do this much more efficiently.

I agree the noise is originating in the charger, not the EVSE, but different EVSE models will have different amounts of filtering. The very fact that we call it RFI (radio-frequency interference) filtering suggests that it is not tuned to audio frequencies, as mogur has suggested.

The charger in the car most likely chops the incoming 60 Hz power into a higher frequency that facilitates rectifying and transforming the power to the voltage required by the battery. Such switching power supplies introduce lots of harmonics, multiples of the fundamental chopping frequency, but I would expect all these frequencies to be above the audio range. However, imbalances in the switching circuitry could introduce sub-harmonics in the audio range. Perhaps this is what folks are hearing.

As you said, the charger in the LEAF is switching at a frequency that is orders of magnitude over audible range, so I doubt seriously this is causing a 60hz-ish buzz, which is what it sounds like to me. 60hz radiated noise is almost always caused by arcing!

The LEAF's on-board charger is power-factor corrected, and also has a substantial noise filter before it leaves the car:

I doubt seriously this is normal after hearing the noise.

-Phil

 

[Christopher]

As I mentioned before, I don't believe this has anything to do with the EVSE.

Yeah, many people have made the same comment. I only mention the modified EVSE and the "eyebrow-raising" in my original post because if I do have to go to the dealer or call an electrician, I'll likely have to deal with their initial skepticism.

However, it's becoming apparent from this thread and some private messages that this noise issue is not specific to my electrical system or my car. Through the help of someone else with the problem, I'm now expecting contact directly from Nissan. They do seem to be looking into the issue.

I will volunteer to stop by your place next time I'm in the southbay and check it out if you have not found the source of the problem by then. Are you available anytime during the day on weekdays, maybe at lunchtime?

If you are comfortable with it, I recommend you open your panel and start charging on 240v to see if you can locate the source of the noise. In particular, look for any screws or terminals that are discolored.

I'm waiting to call an electrician given what seems to be developing but I would be happy to have you look at my panel! I'm not comfortable messing with it myself. I take it the fact that there's no noise at the panel (or anywhere else) when using a higher wattage/amperage device (my dryer) on the same circuit doesn't dissuade your suspicion of an issue at my panel?

Anyway, if you're still up for checking it out, I'm normally available to meet with you any day of the week and any time as long as I don't happen to have conflicting plans. I'll PM you with further info. Thanks!

 

[hill]

As I mentioned before, I don't believe this has anything to do with the EVSE. If you are hearing direct audible noise from your panel/subpanel this does not sound good! Usually noise indicates arcing, which would definitely cause plenty of EMI/RFI using the AC wiring as an antenna.
. . . . . . . . . . . . . snip
If you are comfortable with it, I recommend you open your panel and start charging on 240v to see if you can locate the source of the noise . . . . . . . . . . snip
-Phil

BINGO -good news and bad news. First the good:
SoCal Edison (too pathetically incompetant to calibrate our TOU kWh meter) finally came out and re-installed our good ol' fashion mechanical kWh meter.

Bad news: Yes ... while our main panel was open, Edison showed us clear evidence of arcing. Yes ... we are FUMING! Someone's incompetance/negligence could have burned down our home, had we ignored this. Here's to hoping that a certain installer/contractor will do the right thing ... quickly.

.

 

[LEAFer]

Bad news: Yes ... while our main panel was open, Edison showed us clear evidence of arcing. Yes ... we are FUMING! Someone's incompetance/negligence could have burned down our home, had we ignored this. Here's to hoping that a certain installer/contractor will do the right thing ... quickly.

.

Please give us a little more info.
1. The "installer/contractor" you are refering to ... installed what ? (PV, EVSE, etc).
2. The evidence of arcing was evident exactly WHERE in the main panel ?
3. Did the SCE employee indicate what he thought was the cause of the arcing ?

 

[Ingineer]

Bad news: Yes ... while our main panel was open, Edison showed us clear evidence of arcing. Yes ... we are FUMING! Someone's incompetance/negligence could have burned down our home, had we ignored this. Here's to hoping that a certain installer/contractor will do the right thing ... quickly.

I hate being right sometimes, but I'm glad you caught it before something bad happened!

Did it get fixed? What was arcing?

-Phil

 

[hill]

[I hate being right sometimes, but I'm glad you caught it before something bad happened!

Did it get fixed? What was arcing?

-Phil

Our arcing seems to be related to the TOU install 4 months ago ... not our AV EVSE install. In fact AV immediately sent out the regional contractor manager (Marty) this morning. Great guy. He pointed out the arc is typical of striking a live lead against the neutral lug. The utility simply noticed it when they put a normal (non-TOU) meter back in the socket yesterday. No one else accessed that part of the panel prior to its install. Here's the base of our main panel ... and a closeup of the arc:

Long story short, AV ran tests and assured us it's not their/our EVSE. We'll now have to try to get a hold of our PV installer, as the noise is most closely coming from their 2 locations. The noise only arises when the car is charging. AND . . . the noise (during charging) EVEN happens regardless whether it's night time (Inverters turn off) or day time.

BTW ... that "week or two" ago ... that Nissan said they be getting back to us about this issue? Hasn't that time frame expired .... days ago?

.

 

[turbo2ltr]

Nothing to see here, move along...

 

[hill]

Nothing to see here, move along...

You're much more confident than I am, when the scenario is noise during charging, emanating from or near PV inverters, whether they're running or not. You're basing "nothing to see here, move along" ... on what.

 

[Coffee_Slurry]

Mine's even weirder.

During charging, the car is pretty quiet, and the Blink is silent, but the CONDUIT makes a shrill high-frequency raspy hiss noise. Not loud, but if I had to sit in the silent garage for long it would get annoying.

This is metal conduit carrying only the 240v red & black & ground wires.

It's not subtle. Where the conduit bends around a corner above the water heater -- that's where I hear it most.

<shrug>

 

[planet4ever]

Those are the electrons' tires screeching. :lol: Try charging at a slower rate.

 

[tbleakne]

Mine's even weirder.

During charging, the car is pretty quiet, and the Blink is silent, but the CONDUIT makes a shrill high-frequency raspy hiss noise. Not loud, but if I had to sit in the silent garage for long it would get annoying.

This is metal conduit carrying only the 240v red & black & ground wires.

It's not subtle. Where the conduit bends around a corner above the water heater -- that's where I hear it most.

<shrug>

This might be the possible effect I was describing, because the conductors in the conduit are free to vibrate. There certainly should be no connections to arc in the middle of a conduit run. If there were, this would be a bad thing. I was also speculating that the electrical filter in the Leaf's charging circuit might not be that effective down in the audio band.

I would think an arcing sound would be chaotic, with fluctuations on different time scales, while a steady hiss would be more like what I am describing. I am not sure about "raspy."

In your case, you only hear the sound while charging, right? The conduit is dedicated to the Blink, so there is no way to test the conduit with a similar load other than charging ? If you could record the sound, there is probably software floating around to analyze its spectrum.

 

[LEAFer]

You could invite a non-LEAF owner over to charge. Volt, Tesla (with adapter), Ford Ranger (with adapter), etc.

 

[hill]

How's that Nissan feedback coming along ... you know ... where they'll get back to us in a week or two?

(crickets :? )

 

[LEAFer]

Thanks for that "crickets" update

After the Holiday weekend ... I sent a reminder email yesterday morning, and got a fast reply. I requested Nissan contact hill, GroundLoop, and jsnable direct. He said he will pass that along. ( I had already requested they contact Christopher at least a couple of weeks ago. )

As regards parts ... the shipment from Japan was delayed, and the delays will probably add an extra week. After internal testing they'll be back at my place (their third visit) the following week, but it's not yet scheduled.

The above named members may PM me for additional info and/or PM me when Nissan has made first contact with them. Any other "weirdness" in noise/interference while charging should still be reported here; Nissan is monitoring for this.

 

[Christopher]

After the Holiday weekend ... I sent a reminder email yesterday morning, and got a fast reply. I requested Nissan contact hill, GroundLoop, and jsnable direct. He said he will pass that along. ( I had already requested they contact Christopher at least a couple of weeks ago. )

Don't hold your breath on being contacted by Nissan regarding this issue. I haven't heard a peep. They don't seem particularly interested in talking to me but then perhaps they were just humoring LEAFer by getting my contact info through him. ;-)

Meanwhile, I'm just waiting to see if anything comes of LEAFer's involvement with Nissan and these mysterious parts. Hey LEAFer, so do these visits come at night under the cover of darkness? Do you have to apply masking tape to a window in the shape of an "X"? Or maybe that would be the shape of a zero given Nissan's LEAF marketing?

 

[LEAFer]

Hey LEAFer, so do these visits come at night under the cover of darkness? Do you have to apply masking tape to a window in the shape of an "X"? Or maybe that would be the shape of a zero given Nissan's LEAF marketing?

More like "Z" ... mark of the Zerro ! :lol: Ole ! :lol: