Unable to charge using NEMA 14-50 outlet in garage and Mobile Connector

[Federico]

Here are the images from the back of the outlet (as much as I could pull the outlet after opening the 2 holding screws). I also checked the voltage ...it is 250v for slots on sides and 120v from each of two sides to the bottom slot).

Hope this gives you all some insight into what I am facing.

It looks good, but take a photo of the front faceplate to make sure the ground (bare wire) in on the top (half rounded). The next step should check the panel (you will need to remove 4 screws) to see if the ground is connected.

Plugshare is a great app, but some free chargers are Chargepoint, which means you need to register with them (is free but you need to add a credit card), they will send you a card for free but you can add it to your Apple Wallet without any issue.

 

[pete_shaw]

Does the car charge using the 5-15 regular wall outlet? If it doesn’t work then you could have a Tesla cord issue.

Yes, it does.

 

[pete_shaw]

It looks good, but take a photo of the front faceplate to make sure the ground (bare wire) in on the top (half rounded). The next step should check the panel (you will need to remove 4 screws) to see if the ground is connected.

Plugshare is a great app, but some free chargers are Chargepoint, which means you need to register with them (is free but you need to add a credit card), they will send you a card for free but you can add it to your Apple Wallet without any issue.

Thanks again. I will likely attempt to open the panel tomorrow but from what I recall when the electrician last opened it, it looked like old mess.

 

[NR427]

I doubt your outlet was installed to code with what looks like exposed romex. That would make me question your "licenced" electrician.

 

[pete_shaw]

I doubt your outlet was installed to code with what looks like exposed romex. That would make me question your "licenced" electrician.

Don't know much about it but expecting these guys claiming to be pro definitely know the local code and understand it is part of their job. For now my first priority is to see if this even can work.

 

[Timbo2]

I doubt your outlet was installed to code with what looks like exposed romex. That would make me question your "licenced" electrician.

Many towns in NJ are "flexible" with exposed romex in garages as they aren't considered living spaces. For example I've had two different sets of permitted work done in my garage with exposed romex.

 

[COrocket]

Yes, it does.

I’d be pretty insistent that it’s an outlet issue then

 

[MrMassTransit]

Here are the images from the back of the outlet (as much as I could pull the outlet after opening the 2 holding screws). I also checked the voltage ...it is 250v for slots on sides and 120v from each of two sides to the bottom slot).

Hope this gives you all some insight into what I am facing.

When you say you checked the voltage - I assume you have a multimeter? You mention that from the two side slots (the hot slots) to the bottom slot (the neutral) is 120v. That’s good. Did you try to measure from a side slot to ground (the fourth point which is more of a circle than a slot)? If properly grounded, you should get 120v. I would guess that you will actually get 0, indicating the ground is not connected. If you do get this result, just call the electrician and tell him how you tested the outlet. That would definitively prove that there is something wrong with his work.

 

[Feathermerchan]

He said above that the 5-15 works fine.

 

[eprosenx]

Just tuning in a bit late to this thread... A few comments:

I'll bet he wired the ground to the neutral, or did not terminate the ground.

Ground and neutral should be bonded at one point of the electrical system (typically at the service entrance panel) and so they have 0v of potential between them. Even accidentally inverting the two the UMC would have no idea. It is not actually even connected to the neutral pin in the slightest. It is just testing the ground pin, and even if neutral were hooked to the ground pin it would have no way to know that.

I doubt your outlet was installed to code with what looks like exposed romex. That would make me question your "licenced" electrician.

That looks like romex inside of an unfinished wall. This is commonly allowed I think, though there are rules to keep people from hanging crap from it, etc... (so vertically it is often OK, but if horizontal it needs to be above a certain height or something like that)...

When you say you checked the voltage - I assume you have a multimeter? You mention that from the two side slots (the hot slots) to the bottom slot (the neutral) is 120v. That’s good. Did you try to measure from a side slot to ground (the fourth point which is more of a circle than a slot)? If properly grounded, you should get 120v. I would guess that you will actually get 0, indicating the ground is not connected. If you do get this result, just call the electrician and tell him how you tested the outlet. That would definitively prove that there is something wrong with his work.

You should be able to test as follows with a multimeter:

Hot 1 to Hot 2 (side slots) ~240v
Hot 1 to neutral ~120v
Hot 2 to neutral ~120v
Hot 1 to ground ~120v
Hot 2 to ground ~120v

Now the one thing with the install that I think might be a technical violation is that the metal box needs to be grounded. The ground wire should be connected to the metal box with a grounding screw in addition to the receptacle.

I can understand why the electrician might be a bit grumpy to come back out as this is an extremely simple install and he might have already checked it with a multimeter. There is a good chance the issue is with the UMC itself. As others have said, find another 14-50 receptacle that is known good and test yours with your car. Also, another option would be to find another UMC and test it with your receptacle and car (or someone else's car). I know my local Tesla group would be more than happy to find someone to come help you if you were local (it is a good community!). There may be something similar near you.

But now on to the more concerning and scary possibilities:

It is possible that something is fundamentally wrong with your electrical system in that perhaps your neutral and ground are not properly bonded together. The UMC would pick up on this and refuse to charge. Though I would think that would also impact 120v charging. Other possible concerns would be a "loose neutral" between your house and the utility transformer. It is possible the UMC could detect this by noticing diverging voltages from the two hots to neutral, but it would not be able to detect that on the 120v charging. I am not sure what all it checks for. Regardless, that is an extremely dangerous situation (for the whole house, regardless of EV charging) and would need to be resolved ASAP.

But there is a good chance the issue is just a bad UMC (or something wrong with your car).

Oh, and if you do feel comfortable enough to safely take the panel cover off then post a lot of pictures here of the wire as it comes into the box and its terminations and of the box itself and we may be able to provide advice. One thing we will be looking for is the "neutral to ground" bonding screw or strap. Modern ones are green in color (screws).

Good luck! Please report back on the resolution!

 

[pete_shaw]

When you say you checked the voltage - I assume you have a multimeter? You mention that from the two side slots (the hot slots) to the bottom slot (the neutral) is 120v. That’s good. Did you try to measure from a side slot to ground (the fourth point which is more of a circle than a slot)? If properly grounded, you should get 120v. I would guess that you will actually get 0, indicating the ground is not connected. If you do get this result, just call the electrician and tell him how you tested the outlet. That would definitively prove that there is something wrong with his work.

You're right. The voltage between either of the side to the top point is 0v. However, from the side to the bottom is 120v. If this is conclusive evidence of the grounding problem, I now have some solid facts to ask the electrician to address the issue without debating if the issue with the equipement or the outlet. Thank you so much.

 

[pete_shaw]

Just tuning in a bit late to this thread... A few comments:



Ground and neutral should be bonded at one point of the electrical system (typically at the service entrance panel) and so they have 0v of potential between them. Even accidentally inverting the two the UMC would have no idea. It is not actually even connected to the neutral pin in the slightest. It is just testing the ground pin, and even if neutral were hooked to the ground pin it would have no way to know that.



That looks like romex inside of an unfinished wall. This is commonly allowed I think, though there are rules to keep people from hanging crap from it, etc... (so vertically it is often OK, but if horizontal it needs to be above a certain height or something like that)...



You should be able to test as follows with a multimeter:

Hot 1 to Hot 2 (side slots) ~240v
Hot 1 to neutral ~120v
Hot 2 to neutral ~120v
Hot 1 to ground ~120v
Hot 2 to ground ~120v

Now the one thing with the install that I think might be a technical violation is that the metal box needs to be grounded. The ground wire should be connected to the metal box with a grounding screw in addition to the receptacle.

I can understand why the electrician might be a bit grumpy to come back out as this is an extremely simple install and he might have already checked it with a multimeter. There is a good chance the issue is with the UMC itself. As others have said, find another 14-50 receptacle that is known good and test yours with your car. Also, another option would be to find another UMC and test it with your receptacle and car (or someone else's car). I know my local Tesla group would be more than happy to find someone to come help you if you were local (it is a good community!). There may be something similar near you.

But now on to the more concerning and scary possibilities:

It is possible that something is fundamentally wrong with your electrical system in that perhaps your neutral and ground are not properly bonded together. The UMC would pick up on this and refuse to charge. Though I would think that would also impact 120v charging. Other possible concerns would be a "loose neutral" between your house and the utility transformer. It is possible the UMC could detect this by noticing diverging voltages from the two hots to neutral, but it would not be able to detect that on the 120v charging. I am not sure what all it checks for. Regardless, that is an extremely dangerous situation (for the whole house, regardless of EV charging) and would need to be resolved ASAP.

But there is a good chance the issue is just a bad UMC (or something wrong with your car).

Oh, and if you do feel comfortable enough to safely take the panel cover off then post a lot of pictures here of the wire as it comes into the box and its terminations and of the box itself and we may be able to provide advice. One thing we will be looking for is the "neutral to ground" bonding screw or strap. Modern ones are green in color (screws).

Good luck! Please report back on the resolution!

Thank you for a detailed helpful post eprosenx. The easiest part I could understand without having to reread was about voltages between diff leads. The voltage between Hot to Ground is 0v but hot to Neutral is 120v.

My 120v outlet in the garage worked fine and Tesla charges with that without complain. The part about "loose neutral" in this context I couldn't easily understand due to my lack of familiarity there but this helps talk to me with the electrician and convince him to make the visit and throroughly check this out, unlike what he did at the end of install.

 

[mongo]

You're right. The voltage between either of the side to the top point is 0v. However, from the side to the bottom is 120v. If this is conclusive evidence of the grounding problem, I now have some solid facts to ask the electrician to address the issue without debating if the issue with the equipement or the outlet. Thank you so much.

Yep, that shows ground is not connected at the breaker panel, assuming the bare wire was secure in the outlet (which it looks like it was from your pics).

And as @eprosenx mentioned, there should be a ground connection to the metal box. Something like this:
Should I ground the metal box for 14-50 outlet?

Given your 120V to neutral readings, your house neutral seems fine.

 

[KerryOH]

If you want to take a ride up the Garden State Pkwy to Belleville (exit 150) I have a working 14-50 outlet in my driveway. Send a private message and I’ll send details etc. you can also test my UMC on your M3.

 

[mswlogo]

Two comments.

Technically the outlet box should be grounded. Often the box gets grounded through the outlet connected to face plate and the cover screws to the box but that’s not how it should be done. That won’t cause an error in charging though. It should be looped to the box then out to the outlet.

I never use a multimeter on this stuff. The smallest leakage can cause misleading readings. I always use a “coil” type meter that actually pulls a load.

I’ve had my “Knopp” tester for over 30 years and I had a heck of time finding any coil tester besides the one I have which has not changed a bit. Honestly, I can’t do the work with out it. You need to pull a little bit of current to what’s really there.

https://www.amazon.com/Knopp-K-60-Cat-Number-14460/dp/B003A7T5KG

It is possible the adapter or UMC has an issue. But I think OP’s Electrician is kind of jerk. If the problem is his fault it should be no charge. If it’s customer equipment customer should pay for the service call. But either way he should be happy to come out. Even if it’s customers equipment.

Might want to find another electrician. I’d say it’s 50-50 chance house vs adapter/UMC.

One other simple thing to try (just as a data point). Shut off every breaker accept the EV and try it. Could be some weird load in the house.

 

[Jaywlker]

The electrician checked things when he finished the installation but hasn't come out to help (yet) after I told him about the charger issue. On the phone, he sounded like he shouldn't have to come since his work was "all good". It has got to be something to do with Tesla charging equipment according to him. Its a little uncomfortable to press him for this based on his pushback on my call today.

Time to find a new electrician!

 

[MrMassTransit]

You're right. The voltage between either of the side to the top point is 0v. However, from the side to the bottom is 120v. If this is conclusive evidence of the grounding problem, I now have some solid facts to ask the electrician to address the issue without debating if the issue with the equipement or the outlet. Thank you so much.

No problem! Let us all know how it turns out, but that definitively indicates a problem with the ground on that outlet. On your 120v outlet that you tested with, you can do the same thing (from the small slot (hot) to the round hole) and you’ll get 120v from hot to ground (since the adapter worked fine off this outlet, I’m sure the ground will test properly). Given that the 120v outlet seems to be fine (as well as your hot to neutral readings), my guess is it is just an issue with ground not being connected rather than a larger issue with how your panel is wired or the grounding system of your residence.

Also, everyone else is correct that the outlet box should be grounded also but that is not the cause of your issue.

 

[Can37]

Here are the images from the back of the outlet (as much as I could pull the outlet after opening the 2 holding screws). I also checked the voltage ...it is 250v for slots on sides and 120v from each of two sides to the bottom slot).

Hope this gives you all some insight into what I am facing.

The connections are good but it looks like box is not grounded, this is a sure sign the electrician is a problem. I would have another electrician come in and fix the box and take a look at the connection in the main panel. Did you check the voltage to the ground pin?

If the box is not grounded, this setup is very unsafe!

 

[pete_shaw]

No problem! Let us all know how it turns out, but that definitively indicates a problem with the ground on that outlet. On your 120v outlet that you tested with, you can do the same thing (from the small slot (hot) to the round hole) and you’ll get 120v from hot to ground (since the adapter worked fine off this outlet, I’m sure the ground will test properly). Given that the 120v outlet seems to be fine (as well as your hot to neutral readings), my guess is it is just an issue with ground not being connected rather than a larger issue with how your panel is wired or the grounding system of your residence.

Also, everyone else is correct that the outlet box should be grounded also but that is not the cause of your issue.

This has now become a bit of education for me in electrical outlets. Thanks for guiding me and staying with me. I just checked the 100v outlet for voltage between the ground hole to each of the two slots . Oddly enough there is 110v from one of the slots to the ground but 0v from the other slot to the ground. Then I checked few random 110v outlets throughout the house and exactly the same observation. (Of course the Tesla mobile connector did work with my 110v outlet).

This made me go back to the observation I made earlier this morning (between 4-5 am) I had about new 240v outlet. I retested the voltage between each of the slots on side to the top hole for ground. This time I got bout 60v from one side to the ground and close to 0v (needle moved a tad bit) from the other side. This time I made sure to wiggle the proble many times to ensure I am not missing the connection point and providing wrong information here that can lead to of course misdiagnosis. I feel like an idiot because previously I reported that there was 0v from each side slot to the ground on top of outlet. Now one of the slots measures 60v to the ground.

 

[pete_shaw]

Thank you all for such great guidance and support. I am truly appreciative of the help. I have an update in my previous observation that I reported above.

Update:
I just checked the 100v outlet for voltage between the ground hole to each of the two slots . Oddly enough there is 110v from one of the slots to the ground but 0v from the other slot to the ground. Then I checked few random 110v outlets throughout the house and exactly the same observation. (Of course the Tesla mobile connector did work with my 110v outlet).

This made me go back to the observation I made earlier this morning (between 4-5 am) I had about new 240v outlet. I retested the voltage between each of the slots on side to the top hole for ground. This time I got bout 60v from one side to the ground and close to 0v (needle moved a tad bit) from the other side. This time I made sure to wiggle the proble many times to ensure I am not missing the connection point and providing wrong information here that can lead to of course misdiagnosis. I feel like an idiot because previously I reported that there was 0v from each side slot to the ground on top of outlet. Now one of the slots measures 60v to the ground.