It sounds like there is some funky mystery in that wiring run somewhere, like maybe a bad splice or something. I wonder if you could use like a continuity checker to read for the resistance between each wire at the outlet and and back at the panel end to see if there is something semi-disconnected or loose along the way. These kinds of 120V outlet circuits usually go in and out of multiple outlets, so maybe something isn't very tight.
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Help to understand home charging options?
- Thread starter Litigate28
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"Ground Fault" could mean a couple of things. Usually means that there is an unwanted current path between a phase and ground. But in this context it could mean that the ground is not there or is not good. I'd say first thing to do is check that the UMC charges the car properly at some other outlet thus verifying that it and the car's charging equipment are OK. Since everything worked before the new outlet was installed suspicion is clearly focused on that but best to be 100% certain that the car's equipment is up to snuff.
When the UMC shows the fault is it plugged into the car or does it show that light when it is plugged in to the new outlet but the car is not connected?
Next: check the electrician's work. Start with a "bug" (outlet tester). What does it report? There are 6 ways to connect 3 wires to 3 terminals and only one of them is correct. Be sure the white wire is connected to the silver colored screw, the black wire is connected to the brass colored screw and the bare wire to the grey screw with the hexagonal head.
If the bug shows normal and the wires are on the right terminals and the UMC works in another outlet then you have a mystery the unraveling of which is going to involve other types of testing. If you have a volt/ohm meter measure the voltage between the T shaped slot and the other slot. It should be 120V. The T shaped slot to the ground pin should read a fraction of a volt. The straight slot to the ground pin should measure the same or very close to the slot to slot measurement value. Turn the breaker off and check that the straight slot measures at most a fraction of a volt to ground and to the T slot. Now measure the resistance between the T slot and the ground pin. I should be small (less than a couple of ohms). Now measure the resistance between the straight slot and the ground pin. It should be very high or off scale.
When the UMC shows the fault is it plugged into the car or does it show that light when it is plugged in to the new outlet but the car is not connected?
Next: check the electrician's work. Start with a "bug" (outlet tester). What does it report? There are 6 ways to connect 3 wires to 3 terminals and only one of them is correct. Be sure the white wire is connected to the silver colored screw, the black wire is connected to the brass colored screw and the bare wire to the grey screw with the hexagonal head.
If the bug shows normal and the wires are on the right terminals and the UMC works in another outlet then you have a mystery the unraveling of which is going to involve other types of testing. If you have a volt/ohm meter measure the voltage between the T shaped slot and the other slot. It should be 120V. The T shaped slot to the ground pin should read a fraction of a volt. The straight slot to the ground pin should measure the same or very close to the slot to slot measurement value. Turn the breaker off and check that the straight slot measures at most a fraction of a volt to ground and to the T slot. Now measure the resistance between the T slot and the ground pin. I should be small (less than a couple of ohms). Now measure the resistance between the straight slot and the ground pin. It should be very high or off scale.
What's odd is the 5-15 was working before he tried putting in the 5-20, and now even when he put the 5-15 back it's not working anymore. So my guess is something happened there that stopped it from working?
Just a quick thanks to you and Rocky and the others that are taking the time to help me out. This has gotten quite frustrating. To answer your questions...
The UMC is fine, I tried it in about 6 plugs inside the house and it lights up green perfectly, so it is not the UMC. Also the red light happens right when I plug it in, so this is before I even try plugging it into my car. It is the 4 blink red light which according to the manual means ground fault. I actually have three sets of outlets in the garage and on all of them, it flashes the red light 4x indicating the ground fault. The electrician tried all three outlets, opening them up and seeing what he could do.
Outlet "1" is the one he tried to upgrade with the two sets of 5-15 in there that we've been talking about. He put the 5-15 back in so the 5-20 is now just sitting out there. Previously it would work, now it doesn't as I mentioned above. Two interesting things about his attempt: 1) he had one of these things to test the ground:
He had that plugged into one socket, and it showed the lights for "Correct." As soon as he would plug in the UMC, it would change to "Open Ground." He couldn't figure out why. At some point he did the voltage tester and found some current coming in from the ground too.
The second interesting thing is the only thing he did change from when he opened it up to when he gave up and put it back as he found it, was removing this loose piece of wiring that was wrapped around the ground:
This small piece was on before, and the UMC worked. He took it off and supposedly put everything back on the way he found it, and now it doesn't work. Could this small tiny piece make the ground work?
Last piece of info: The other outlet on the same circuit in the garage also gave the red lights, he tried taking that apart and said it looked properly grounded so he couldn't do anything. There was one more outlet in the garage on a separate circuit. Also showed red when plugged in. He took that apart and said it wasn't grounded, but when he rewired it to be "grounded" several other things stopped working in the house (lights in garage, for some reason the AC) so he said that the ground was apparently being used to power something.
I don't have a voltmeter so maybe I should purchase one and do these steps to see what is going on. If these pictures or information however help diagnose anything, that would be even better. Thanks again everyone.
I'm noticing a lot of description of the electrician checking the outlets. At no point do I see any mention of him checking the other end of the wiring run to see what that grounding wire is doing. I and others have mentioned that is just as important and very likely could be where the problem lies. Did he really never check that ground wire at the panel?
That is really disturbing and seems very much to indicate that the grounding wire for that circuit is hooked up somewhere to something it shouldn't be. I think it's somewhere in the panel or along the wiring run. Ground should never have current flowing through it or be used to power anything. If he just tossed off that comment as if it were normal and wasn't shocked or disturbed by that idea, I would really get a bad feeling about that guy's competence.
A little background on these 120V circuits: People, including amateur electricians sometimes fall into a little trap, where they think how ground and neutral are both supposed to be at 0V, so it doesn't matter what you do with them, and you can tie them together or interchange them however you want. But that's not the case. For 120V circuits, the loop of current flow is through one hot wire and that neutral wire. Electric code is very specific that ground and neutral must be kept separate all throughout all of the branch circuits in the house, and they are to be tied to each other to keep that 0V only in one place--your main electric panel. If there are indications that there might be some current flow in that ground wire in or near an outlet, it seems likely that ground and neutral are touching somewhere, which may be causing some of that current from neutral to pass through a parallel path in the ground wire. And that could be causing the ground and/or neutral to jump around off of 0V, which the UMC may be detecting.
Apologies for not answering your previous question - he did go check the panel wiring and came back and said everything looked good there. I presume this meant the ground wiring but I can't be sure.
You're renting, correct?
If so, I suggest you start doing what you can to limit your liability towards this situation. You do not want to be responsible or liable for what's going on with this house's wiring and you do not want to be killed or impoverished if something does go wrong with the wiring.
One of the interesting skills in life that's not too well advertised as an important life skill is understanding how to hire and use people who know more about a thing than you do. Your electrician behaved in a very odd way; it is their specific profession to understand things like "if I disconnect this wire (that should be totally unrelated) those lights go off." Residential electrical systems are not actually tremendously complex and behavior like that should be easy to track down.
If you rent and wish to live there for a long time, I would communicate with your landlord and offer to pay for a tesla approved electrician to install a proper reasonably large current 240v circuit in the garage. While this work is underway make sure the electrician corrects all the other gremlins in the house that likely include randomly wired and daisy-chained outlets, neutrals pulled from one circuit to another, multiple hots run to breakers, etc. Any seasoned electrician will have seen it all and understand likely causes, risks, and remedies. You will likely have many fun discussions with your landlord; expect to pay for it yourself if you actually want it done.
Or
Stop touching things and charge elsewhere. Put things back together and stop using those outlets.
If so, I suggest you start doing what you can to limit your liability towards this situation. You do not want to be responsible or liable for what's going on with this house's wiring and you do not want to be killed or impoverished if something does go wrong with the wiring.
One of the interesting skills in life that's not too well advertised as an important life skill is understanding how to hire and use people who know more about a thing than you do. Your electrician behaved in a very odd way; it is their specific profession to understand things like "if I disconnect this wire (that should be totally unrelated) those lights go off." Residential electrical systems are not actually tremendously complex and behavior like that should be easy to track down.
If you rent and wish to live there for a long time, I would communicate with your landlord and offer to pay for a tesla approved electrician to install a proper reasonably large current 240v circuit in the garage. While this work is underway make sure the electrician corrects all the other gremlins in the house that likely include randomly wired and daisy-chained outlets, neutrals pulled from one circuit to another, multiple hots run to breakers, etc. Any seasoned electrician will have seen it all and understand likely causes, risks, and remedies. You will likely have many fun discussions with your landlord; expect to pay for it yourself if you actually want it done.
Or
Stop touching things and charge elsewhere. Put things back together and stop using those outlets.
These are definitely attention getting.
If you want to pursue this further then yes, that will be necessary. But get one with a clamp-on probe that can measure current too because it looks as if "objectionable current" (that is, any current that flows in the ground wire) might be involved.
JPoldo
Member
Make sure the neutral (white) wire at the panel is screwed down tightly. I worked on a panel this week and several neutral wires were loose. If loose at panrl and ground/neutral touching in another outlet box will cause current to flow through ground which is very bad!
brucet999
Active Member
A 20A breaker is exactly right for the pictured outlet, assuming that the wiring is 12AWG CU or 10AWG Al. The breaker is to protect the wiring, and that circuit likely feeds several outlets (two duplex outlets are shown in the pic) so that there could be close to 20A total load on the circuit, even though each of the duplex outlets is rated for 15A.
To use a 5-20, there should ideally be only one dedicated outlet on the circuit.
brucet999
Active Member
No qualified electrician would put a 20A breaker on a 14AWG circuit. It is most likely that the circuit is 12 AWG and it is very easy to verify either at the outlet or the panel;.
Just wanted to say thanks to everyone who helped and contributed. In the end I finally gave up and paid for the 14-50 outlet installation... As someone said earlier some things are just better left to the professionals.
I'll just enjoy the 9-10kw/hr charging now.
I'll just enjoy the 9-10kw/hr charging now.
Looks good!
Are you planning on leaving the mobile charger connected to that? My connection is similar and I've thought about how I'd manage to add some strain-relief to the plug so the weight of the charger isn't supported entirely by the plug.
I've read words to the effect that most of the high current plugs aren't really sturdy enough to survive daily insertion / removal, and that the sturdy ones are $80ish (so you'd know if you have one)
In the long run I'm planning on having my plug replaced by a permanently connected / hardwired clippercreek unit, though I may cobble something together with a semi-permanently installed mobile connector and some strain relief, if I can find a cheap mobile connector.
Yeah that was the plan, just leave it connected. Perhaps if I'm going on a road trip I'll take it with me otherwise I'll take it.
Feel a bit dumb for not doing this sooner. Spent almost two months doing supercharger trips and having only 30-60% charge most of the time. And for a P85D it is a noticeable difference in power. Live and learn.
In that case I'd make a little shelf above the plug to put the mobile charger onto as a strain relief. Chances are if you're leaving it there almost always you won't wear out the plug.
I've found that I only over-pay once to do the job right; if I nibble around the edges and try to cheap out, I typically end up paying and paying and paying...
There are a couple of solutions to wall-mount the body of the mobile connector, below the outlet. These range from commercially-available products, to 3D-printed things, to ad-hoc (but cheap and simple). As an example of the latter, some owners have used a water bottle holder for a bicycle with good results.
(I'm also a member of the "leave it plugged in except for road trips" contingent.)
Bruce.
The most elegant solution is the corded HPWC:
These cost $500 when they are available and seem to have disappeared from the store. I don't know if they will ever come back and I expect they may not because they come set for 40 A which is the most they can take from a 50 A circuit but the catch is that it is legal to install a 14-50R behind a 40 A breaker in which case the maximum allowable is 32 A. The corded version can be set back to 32 A but simple to do as that is you'd probably want an electrician to do it.
The other alternative, of course, is to buy a regular HPWC and have an electrician wire a 14-15P cordset to it. Assuming you had a 50 amp circuit pulled you would then be able to charge at 40 A as opposed to the 32 A you are getting from the mobile charger (which, conservatively, assumes the 14-50R you are plugged into is on a 40 A circuit).
These cost $500 when they are available and seem to have disappeared from the store. I don't know if they will ever come back and I expect they may not because they come set for 40 A which is the most they can take from a 50 A circuit but the catch is that it is legal to install a 14-50R behind a 40 A breaker in which case the maximum allowable is 32 A. The corded version can be set back to 32 A but simple to do as that is you'd probably want an electrician to do it.
The other alternative, of course, is to buy a regular HPWC and have an electrician wire a 14-15P cordset to it. Assuming you had a 50 amp circuit pulled you would then be able to charge at 40 A as opposed to the 32 A you are getting from the mobile charger (which, conservatively, assumes the 14-50R you are plugged into is on a 40 A circuit).
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