Did Anyone Look at this Patent

[Dennis Alwon]

MIKE HOLT sent an email that showed this device trying to get patented. How in the world would this ever be allowed? On a logical level I would argue that it may be safer to have a neutral connected to the ground screw of a receptacle as that would allow for a ground fault to clear.

What is he present danger with this setup.... I could see this as an extra precaution even though it is not code compliant. What are the dangers here with no equipment grounding conductor to carry current?


Look here

https://www.mikeholt.com/files/PDF/Dangerous_Self_Grounding_Outlet_Patent.pdf

 

[dkidd]

Mike Newsletter - Self Grounding Outlet Patent

I thought this was a joke. Its so ridiculous. The person who created this had the insight to patent it but it never occurred to them that if their "invention" was safe and just as good why wouldn't all buildings simply do away with the 3rd conductor and only use two? I thought there were patent...

forums.mikeholt.com

 

[K8MHZ]

I have run across jacked three prong receptacles in the past. I sure don't know how that is patentable

 

[Fred B]

I have run across jacked three prong receptacles in the past. I sure don't know how that is patentable

Maybe he's just looking to make some money on all those jacked receptacles, claiming patent infringement. I think an attorney could turn it around on him and sue for damages if jacked devices cause injury or fire.

 

[Cow]

Correct me if I'm wrong, but patented doesn't mean UL listed.

 

[winnie]

There is another thread on this topic https://forums.mikeholt.com/threads/mike-newsletter-self-grounding-outlet-patent.2556340 and synchro pointed out that the 'claims' of the patent are very very narrow.

The thing that a patent 'owns' is not the disclosure, but the 'claims'. The 'claims' describe exactly what would be considered infringement that the patent owner can sue for.

In particular the claim of this patent is for a receptacle where the ground terminal has a welded bar connecting it to the neutral terminal. A bootleg ground with a wire under the terminals doesn't infringe .

My guess is that the patent examiner ruled out any form of bootleg ground that someone would actually make in the field, and all that was left was a particular form of pre-manufactured bootleg ground.

Of course the examiner was not actually determining if the invention was either safe or useful.

-Jon

 

[480sparky]

A patent is simply a legal means for defending an idea or concept. There's no way it would get any sort of listing, let alone any manufacturer willing to pump 'em out.

 

[Dennis Alwon]

Back to my question... why is this dangerous. There is no equipment grounding conductor so the only time the neutral will see current is on a ground fault.

 

[480sparky]

Back to my question... why is this dangerous. There is no equipment grounding conductor so the only time the neutral will see current is on a ground fault.

How could the neutral not see current if there's a load?

 

[Dennis Alwon]

How could the neutral not see current if there's a load?

I said the neutral will see the load not the equipment grounding conductor since there isn't any. The equipment grounding conductor will use the neutral as a ground fault

 

[480sparky]

I said the neutral will see the load not the equipment grounding conductor since there isn't any. The equipment grounding conductor will use the neutral as a ground fault

I'm confused.

....... so the only time the neutral will see current is on a ground fault.

So how can the neutral only see current is during a ground fault? Where does the current go when there's a load?

 

[Dennis Alwon]

I'm confused.



So how can the neutral only see current is during a ground fault? Where does the current go when there's a load?

Ken I don't know what you are saying. I never said the neutral wouldn't see current.

On second thought I do see the issue with this install....If I plug in a piece of equipment that has a ground and I touch the equipment and another grounded object then the path could come threw the person in contact with it. Basically another path for the neutral current.

I was thinking just about a ground fault and the current just going between the neutral and the hot

 

[480sparky]

Lemme ask you this, Dennis: What would happen to you if that circuit's neutral was opened somewhere between you and the panel and you touched the grounded metal case of the load (washing machine, fridge, sump pump)?

 

[hillbilly1]

Lemme ask you this, Dennis: What would happen to you if that circuit's neutral was opened somewhere between you and the panel and you touched the grounded metal case of the load (washing machine, fridge, sump pump)?

That’s the reasoning behind having the ground and neutral separated once it leaves the service, just an extra layer of protection against shocks. I’m sure Dennis already knows that, he is probably just stating under normal conditions, it’s not a problem. As far as adjacent grounded surfaces, it would need to be a severe voltage drop to create enough potential to be dangerous in most cases.

 

[480sparky]

That’s the reasoning behind having the ground and neutral separated once it leaves the service, just an extra layer of protection against shocks. I’m sure Dennis already knows that, he is probably just stating under normal conditions, it’s not a problem. As far as adjacent grounded surfaces, it would need to be a severe voltage drop to create enough potential to be dangerous in most cases.

If the neutral is open, then touching a grounded device plugged into this miracle receptacle would put you in series with any load if you ground yourself. I'm fairly certain you'd get one helluva shock.

 

[hillbilly1]

If the neutral is open, then touching a grounded device plugged into this miracle receptacle would put you in series with any load if you ground yourself. I'm fairly certain you'd get one helluva shock.

Yes, you would, but that’s not what Dennis and I are saying. Under normal operating conditions, it’s not really a problem. An open neutral would be an abnormal condition.

 

[GoldDigger]

Ken I don't know what you are saying. I never said the neutral wouldn't see current.

On second thought I do see the issue with this install....If I plug in a piece of equipment that has a ground and I touch the equipment and another grounded object then the path could come threw the person in contact with it. Basically another path for the neutral current.

I was thinking just about a ground fault and the current just going between the neutral and the hot

Specifically, a hot to neutral short within a normal piece of equipment whose case is intended to be grounded will put up to half the line voltage on the case. Far worse than the cord EGC wire being simply left disconnected. The NEC recognizes this.

 

[drcampbell]

It could be just the opposite: By owning a patent and squatting, it's possible to prevent anybody from (legally) marketing such a device.

 

[GoldDigger]

It could be just the opposite: By owning a patent and squatting, it's possible to prevent anybody from (legally) marketing such a device.

Thereby doing everyone a service?

 

[Fred B]

Specifically, a hot to neutral short within a normal piece of equipment whose case is intended to be grounded will put up to half the line voltage on the case. Far worse than the cord EGC wire being simply left disconnected. The NEC recognizes this.

I was thinking about that, now if you follow the current flow, a normal 120 circuit the return voltage is on the neutral, if you bond the neutral to the ground at the receptacle, the ground terminal is usually part of the mounting strap, thus when it is installed, it is mechanically bonded also to the metal box but not only that but also the cover plate screws. Thus you (or anyone) will have "access" to the return voltage on the cover plate screws, and if physically contacted by you, you also would potentially (how much potential depends on your level of "ground" contact)become a part of or a parallel return path for that neutral under "normal operating conditions". Not just fault conditions. Doesn't sound good.
I am also thinking "GoldDigger's" statement is part of the reasoning behind the requirements to have GFCI protection when installing or changing a 2 prong ungrounded receptacle to a grounded receptacle with no ground wire. With that in mind I was wondering, if I am replacing 2 prong for 3 prong in this scenario does every receptacle need to be a gfci receptacle or just the first in circuit (like you would for "normal" gfci installation)?
Note that the worst possible case would be to interconnect all of the receptacle ground terminals using, for example, NM with ground without extending to a functioning EGC going back to the panel.