Did Anyone Look at this Patent

[GoldDigger]

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)?

Just the first in the circuit as long as the circuit is not half of an MWBC. New GFCI receptacles come with a supply of "No Ground" stickers to be placed at each downstream receptacle.

 

[romex jockey]

in the broader scope, i applaud MH for using his site for consumer protection & vetting the many new widgets gets our trade is flooded with, looking forward to more of this here! ~RJ~

 

[Dennis Alwon]

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.

Yes, at first I was thinking there wouldn't be an issue with bonding the gr. screw to the neutral and then I realized that a ground fault in the equipment would be an issue by potentially energizing the casing.

You would think that the patent office would not allow this but I guess they are not involved in safety. You know whether this is listed or not home owner's will use it.

 

[LarryFine]

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)?

The latter.

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.

Prohibited.

 

[Peter Furrow]

Yeah but... three wire Systems on a dryer or range pose the same hazards that we discussed under this post, yet, it is permissible by the NEC.
Hazard 1: abnormal condition such as an open neutral & coincidentally a ground fault at the same time would energize the casing ..you get shocked.
Hazard 2: normal condition It’s still a hazard because you can become a part of the parallel return path if you are touching the casing of another piece of equipment or anything that returns back to the source.

But what if the NEC made specific requirements for this miracle receptacle?
For example:
Only be used in a two wire residential system.
Not permissible with metal junction boxes only existing bakelite or plastic junction boxes.
Not permissible with appliances in kitchen or garage.

Overall, I have mixed feelings about the product. Yes, I do see the potential hazards.
But could those hazards be minimized if the NEC made strong stipulations as to where they can be installed and in what conditions.?

I work on a lot of older homes on beach side with two wire systems. We install two- prong receptacles in the bedrooms and in areas where a third ground prong is needed we install a GFCI receptacle. The bootleg receptacle kind of appeals to me.
OK you guys can start throwing rocks at me now. LOL


Sent from my iPhone using Tapatalk

 

[480sparky]

The people who who buy and install this type of device (should they every make it to the store shelves) are the same ones who would NOT install them because they're $1 more than the plain-jane grounded receptables, which is what they'll install anyway.

 

[K8MHZ]

Yeah but... three wire Systems on a dryer or range pose the same hazards that we discussed under this post, yet, it is permissible by the NEC.
Hazard 1: abnormal condition such as an open neutral & coincidentally a ground fault at the same time would energize the casing ..you get shocked.
Hazard 2: normal condition It’s still a hazard because you can become a part of the parallel return path if you are touching the casing of another piece of equipment or anything that returns back to the source.

But what if the NEC made specific requirements for this miracle receptacle?
For example:
Only be used in a two wire residential system.
Not permissible with metal junction boxes only existing bakelite or plastic junction boxes.
Not permissible with appliances in kitchen or garage.

Overall, I have mixed feelings about the product. Yes, I do see the potential hazards.
But could those hazards be minimized if the NEC made strong stipulations as to where they can be installed and in what conditions.?

I work on a lot of older homes on beach side with two wire systems. We install two- prong receptacles in the bedrooms and in areas where a third ground prong is needed we install a GFCI receptacle. The bootleg receptacle kind of appeals to me.
OK you guys can start throwing rocks at me now. LOL


Sent from my iPhone using Tapatalk

I was thinking about the three wire dryer permission and what I realized was that it isn't like a jacked ground. In order for a three wire dryer to be legal, it won't have a neutral. Just 240 volts and the frame ground. The ECG, to be legal, must enclose the two hot conductors. So really, it's not the same thing at all.

 

[LarryFine]

Yeah but... three wire Systems on a dryer or range pose the same hazards that we discussed under this post, yet, it is permissible by the NEC.

Was, not is.

Hazard 1: abnormal condition such as an open neutral & coincidentally a ground fault at the same time would energize the casing ..you get shocked.

That happened to a customer's son. Range lights and clock stopped, two days later son bridged between range and sink, spent a few days in the hospital. 3-wire cord neutral wire pulled out of crimped-on spade terminal in range wiring compartment.

Hazard 2: normal condition It’s still a hazard because you can become a part of the parallel return path if you are touching the casing of another piece of equipment or anything that returns back to the source.

At least with a service, the neutral "represents" the earth. With a branch circuit, it may or may not, especially with a device that has a 50/50 chance of being reverse-wired. This means creating a certain hazard far worse than the risk of having no EGC at all.

But what if the NEC made specific requirements for this miracle receptacle?
For example:
Only be used in a two wire residential system.
Not permissible with metal junction boxes only existing bakelite or plastic junction boxes.
Not permissible with appliances in kitchen or garage.

Still risking a reverse-wired condition that assures that any bonded conductive parts and surfaces are energized!

Overall, I have mixed feelings about the product. Yes, I do see the potential hazards.
But could those hazards be minimized if the NEC made strong stipulations as to where they can be installed and in what conditions.?

Electrons don't follow the NEC rules.

I work on a lot of older homes on beach side with two wire systems. We install two- prong receptacles in the bedrooms and in areas where a third ground prong is needed we install a GFCI receptacle. The bootleg receptacle kind of appeals to me.
OK you guys can start throwing rocks at me now. LOL

Consider yourself stoned.

 

[LarryFine]

I was thinking about the three wire dryer permission and what I realized was that it isn't like a jacked ground. In order for a three wire dryer to be legal, it won't have a neutral. Just 240 volts and the frame ground.

Again, in the past, the 3-wire major appliance circuits used the neutral for grounding, not the EGC as the neutral.

Today, yes, only a major appliance that requires no neutral may be supplied by only two conductors plus the EGC.

 

[Peter Furrow]

LOL Larry!!
I’ll just stick with the GFCI installation and two prong receptacles for all those two wire system homes..
“ everybody must get stoned” Dylan


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[LarryFine]

I’ll just stick with the GFCI installation and two prong receptacles for all those two wire system homes..

And one GFCI can protect downstream receptacles, as with any circuit.

 

[hillbilly1]

I was thinking about the three wire dryer permission and what I realized was that it isn't like a jacked ground. In order for a three wire dryer to be legal, it won't have a neutral. Just 240 volts and the frame ground. The ECG, to be legal, must enclose the two hot conductors. So really, it's not the same thing at all.

The three wire dryer is exactly like the jacked ground. The drive motor is 120 and requires the neutral connection. The bond is a strap that comes with the dryer that can be connected if three wire, disconnected if four wire.

 

[drcampbell]

The three-wire dryer ... drive motor is 120 [volts] and requires the neutral connection. ...

I've often wondered about that. They mass-produced millions of them; how hard (or expensive) would it be to install 240-volt motors? Do that and a three-wire connection is quite sufficient.

 

[LarryFine]

I've often wondered about that. They mass-produced millions of them; how hard (or expensive) would it be to install 240-volt motors? Do that and a three-wire connection is quite sufficient.

Everything in typical dryer is wired from L1 to N, and only the heating element uses L2. This allows a dryer to work equally well on either 120/240v (homes) or 120/208v (apartments) services, except with 75% heating capacity on the latter.

 

[drcampbell]

It's not possible to build a fractional-horsepower motor that runs OK on either 208 or 240? Efficiency's not an issue; the motor consumes maybe 5% of the total power and any "wasted" energy becomes useful heat.

 

[LarryFine]

It's not possible to build a fractional-horsepower motor that runs OK on either 208 or 240? Efficiency's not an issue; the motor consumes maybe 5% of the total power and any "wasted" energy becomes useful heat.

What about drum light bulbs?

 

[hillbilly1]

Inverter drives are getting quite popular on washers, the same could be used on dryers, except 208-240 volt input, the drum light, led with multi volt driver.

 

[retirede]

Inverter drives are getting quite popular on washers, the same could be used on dryers, except 208-240 volt input, the drum light, led with multi volt driver.

Inverter drives are cost-effective on washing machines because they eliminate the need for a complicated mechanical transmission.
An inverter would be an unacceptable added cost to a dryer that runs single speed and single direction.

 

[hillbilly1]

Inverter drives are cost-effective on washing machines because they eliminate the need for a complicated mechanical transmission.
An inverter would be an unacceptable added cost to a dryer that runs single speed and single direction.

Just throwing it out there because it can be done. Changing a dryer to straight 208-240 at this time would not really gain anything due to the neutral is already available, and a cheap workaround with the 120 volt motor. Might be usable in European countries, but do they have 208 volts on their three phase systems there?

 

[GoldDigger]

What about drum light bulbs?

These days most new units used LEDs and the drivers can be designed to any voltage range.