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Electrical Issue?

So I just picked up my MR today (yay!).

Drove it ~100 miles home. Plugged it into brand new, professionally installed 14-50 outlet, and the whole house power flickered within a minute or so. Flickered again an hour or two later while the car was still charging (maybe when it finished?). Neither breaker tripped (the one the car is on, or the entire panel).

The outlet is the Tesla-recommended commercial-grade model. The breaker was installed new with the outlet. Car was charging at 32A.

I just manually dropped the amperage down to 30 and upped the battery limit so it would start charging again to try to see if maybe it was drawing too much. Haven't seen any more flickers yet.

Has anyone else experienced this? Any thoughts? Doesn't make any sense to me that the breakers didn't trip.
 

jjrandorin

Moderator, Model 3, Tesla Energy Forums
Moderator
Nov 28, 2018
15,845
20,552
Riverside Co. CA
who did your install, and did they do a usage calculation on your house? I am not an electrictian (although several people who likely work with electricity for a living post on this board), but flickering lights usually is a load issue, isnt it?

One thing I DO know is, nothing will find electricity deficiencies in your home like charging an EV, with its constant load. throwing something at the wall, I wonder what the size of your service is, and what else you had running (as in, do you have an electric oven? Electric heaters? do you only have 100amp service instead of 200 amp?)
 

eprosenx

Active Member
May 30, 2018
2,076
2,554
Beaverton, OR
So I just picked up my MR today (yay!).

Drove it ~100 miles home. Plugged it into brand new, professionally installed 14-50 outlet, and the whole house power flickered within a minute or so. Flickered again an hour or two later while the car was still charging (maybe when it finished?). Neither breaker tripped (the one the car is on, or the entire panel).

The outlet is the Tesla-recommended commercial-grade model. The breaker was installed new with the outlet. Car was charging at 32A.

I just manually dropped the amperage down to 30 and upped the battery limit so it would start charging again to try to see if maybe it was drawing too much. Haven't seen any more flickers yet.

Has anyone else experienced this? Any thoughts? Doesn't make any sense to me that the breakers didn't trip.

Flickers for the entire house are not a common failure mode if something is installed wrong. Normally we see melted receptacles as the most common mistake.

This does sound serious though. Your 14-50 install may be 100% perfectly done, but having such a high draw load on your house electrical system might have found a latent defect in your main electrical panel or somewhere upstream (the feed from the utility back to the transformer, or the transformer itself).

I recommend being extremely careful with this situation. Until you do some more testing, don’t charge the car while sleeping. Monitor it the next time you charge.

Setting it down just a couple amps may not be enough to avoid what is going on. If you need to get some charge in the car until you figure out what is going on, I might try 16 amps if you had long enough to wait (just during waking hours).

To try to stress test the system of course I would charge at the full 32 amps.

You have three options of people to call:
1. You can call your electrician back and see what they say.
2. You can call your power company and explain the situation and perhaps ask them to come check the tightness of their connectors at the transformer and meter base. Often times they are extremely responsive on this stuff as a loose neutral can cause a house fire.
3. You could call Tesla and ask if they can see anything in the logs. I bet the Tesla might be able to see the blips, but getting someone to actually look at if for you might be impossible.

Myself personally, I would go inspect everything myself in the electrical panel and I would take the covers off and thermal image it while charging with my Flir camera, but I am weird that way. :)

There is the possibility that the power issues were totally unrelated to your house (could be a grid issue), but it seems really coincidental.

I would be curious to see lots of pictures of your install and panel. I am curious what size of service you have, how old your panel is, etc... Perhaps it will give us an idea of how modern or old your electrical system is.
 
  • Informative
Reactions: Matt L

eprosenx

Active Member
May 30, 2018
2,076
2,554
Beaverton, OR
Also FWIW, if something was overloaded this is not the failure mode I would expect. I would expect to blow a breaker, or have voltage dip much more than expected (causing the car to a back off or stop and report a fault), or to have something get hot and overheat.

Flickering lights sounds like a loose or arcing wire. You can have that happen with or without being overloaded.
 
Thanks for the input guys.

Could have been a coincidence, but that’s not common here outside of a storm.

The house was built in 2012, 200A service, 42-pole panel (only 3 open now). All-electric house. I think there are several all-electric houses in this neighborhood.

The electrician didn’t do a usage calculation. I did a very rough one and determined we might have trouble if I tried to get the wall charger installed. VERY non-scientific though.

BTW, this is not the first time we’ve have suspect electrical issues. The others are all smaller though, where we guess just sloppy installations (tripping GFCIs, lights burning out prematurely, etc).
 

eprosenx

Active Member
May 30, 2018
2,076
2,554
Beaverton, OR
Thanks for the input guys.

Could have been a coincidence, but that’s not common here outside of a storm.

The house was built in 2012, 200A service, 42-pole panel (only 3 open now). All-electric house. I think there are several all-electric houses in this neighborhood.

The electrician didn’t do a usage calculation. I did a very rough one and determined we might have trouble if I tried to get the wall charger installed. VERY non-scientific though.

BTW, this is not the first time we’ve have suspect electrical issues. The others are all smaller though, where we guess just sloppy installations (tripping GFCIs, lights burning out prematurely, etc).

Can you post a picture of your panel (so we can see the amps on the breaker handles) and a picture of the service schedule?

So the GFCI thing may be unrelated, but the “lights burning out prematurely” concerns me.

One of the most dangerous conditions to have is to have a loose neutral wire somewhere between your main electrical panel and the utility transformer. When this happens, you end up with random voltages between 0-240v on each of your 120v circuits. This can easily start fires.

Now I kind of doubt this is what is going on since it would be much more noticeable if it was and the Tesla would not make it any worse (since it does not use the neutral) - but I just call it out anyway.

I would probably have my multimeter out and plugged into a wall outlet in my living room watching the voltage while charging the car. Then you might catch the voltage dropping during the event you describe. This is very unscientific and would only monitor one of the two phase legs, but it is better than nothing.
 

eprosenx

Active Member
May 30, 2018
2,076
2,554
Beaverton, OR
So, it turned out to be a complete coincidence. There was work being done on a transformer upstream; the power flickers occurred throughout the entire neighborhood.
o_O

Glad you ran it to ground and glad it was nothing wrong with your wiring!

Enjoy your new car!!!

Also, thank you for reporting back with the result! It helps us all learn and advise others in the future.
 

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