Ground/Neutral Receptacle Connections

[STucker]

Back when I was working in a residential setting(not as an electrician), I would consistently see where homeowners with ungrounded receptacles would replace their old receptacle with one that has a ground, and then jump the ground connection to the neutral in lieu of running a new line with an EGC. Of course, this is bad practice and certainly not code compliant, but it should still provide a path for fault current back to the source.

What I'm wondering is what are the implications? Does it potentially degrade the insulation of the neutral from potentially high currents/temperatures? Are there other issues that would be expected?

 

[LarryFine]

The issue is having current, thus voltage drop, on the neutral, which means the normally-grounded surfaces of the plugged-in device would not be at zero volts relative to earth and/or actually-grounded surfaces nearby, creating a possible shock hazard. And this is presuming intact connections throughout the circuit. Imagine an accidental break in the neutral between the load and the panel.

 

[infinity]

What I'm wondering is what are the implications? Does it potentially degrade the insulation of the neutral from potentially high currents/temperatures? Are there other issues that would be expected?

During a ground fault wouldn't the ungrounded conductor see the same high current as the EGC?

 

[STucker]

The issue is having current, thus voltage drop, on the neutral, which means the normally-grounded surfaces of the plugged-in device would not be at zero volts relative to earth and/or actually-grounded surfaces nearby, creating a possible shock hazard. And this is presuming intact connections throughout the circuit. Imagine an accidental break in the neutral between the load and the panel.

Very good point on the shock hazard, but wouldn't a break in the neutral just result in an open circuit regardless of there being no EGC?

 

[STucker]

During a ground fault wouldn't the ungrounded conductor see the same high current as the EGC?

Unless my terminology is off, Ungrounded conductor=hot, correct?

Doesn't it typically experience the same current as the EGC during a ground fault?

Edit: sorry, I don't think I made a specific point that the existing wiring had no EGC.

 

[480sparky]

Very good point on the shock hazard, but wouldn't a break in the neutral just result in an open circuit regardless of there being no EGC?

It would............. until you touched the grounded portion of anything connected to that circuit when you're grounded. Then YOU end up being the current path.

 

[infinity]

Unless my terminology is off, Ungrounded conductor=hot, correct?

Doesn't it typically experience the same current as the EGC during a ground fault?

Edit: sorry, I don't think I made a specific point that the existing wiring had no EGC.

Right and you're using the neutral as an EGC by connecting a bootleg bonding jumper to it. How would it only "potentially degrade the insulation of the neutral from potentially high currents/temperatures" when the hot leg had the same amount of current?

 

[Jamesco]

It would............. until you touched the grounded portion of anything connected to that circuit when you're grounded. Then YOU end up being the current path.

I f a 3 wire cord and grounding type plug piece of equipment or appliance is plugged into the receptacle the metal enclosure/chassis of the equipment/appliance is connected directly to the neutral conductor. If for any reason the branch circuit neutral conductor connection is broken, open, any where from the receptacle connection to the electrical panel neutral bar connection the metal enclosure/chassis of the equipment/appliance will become energized if the power switch on the equipment/appliance is closed.

Hot from recept >>> to closed switch >>> to Load >>> from load out on neut conductor in cord to neut contact in recept >>> jumper from neut to equipment ground contact on recept >>> back out on the EGC in cord to metal enclosure/chassis of equipt/appliance.

Could prove deadly if a person touches the equipment/appliance while touching any grounded object with any other part of their body.

 

[electrofelon]

I f a 3 wire cord and grounding type plug piece of equipment or appliance is plugged into the receptacle the metal enclosure/chassis of the equipment/appliance is connected directly to the neutral conductor. If for any reason the branch circuit neutral conductor connection is broken, open, any where from the receptacle connection to the electrical panel neutral bar connection the metal enclosure/chassis of the equipment/appliance will become energized if the power switch on the equipment/appliance is closed.

Hot from recept >>> to closed switch >>> to Load >>> from load out on neut conductor in cord to neut contact in recept >>> jumper from neut to equipment ground contact on recept >>> back out on the EGC in cord to metal enclosure/chassis of equipt/appliance.

Could prove deadly if a person touches the equipment/appliance while touching any grounded object with any other part of their body.

So which is more dangerous, no egc, or using neutral as egc?

 

[jaggedben]

It's okay to tie the neutral and EGC together at the outlet as long as you drive a ground rod and connect it for each outlet where you do this.

Just kidding! :lol:

 

[jaggedben]

So which is more dangerous, no egc, or using neutral as egc?

In his scenario neutral tied to EGC is worse. With no EGC the chassis does not become energized.

With that said, don't a lot of tools and appliances have the chassis tied to neutral internally? That would create the same problem.

 

[GoldDigger]

In his scenario neutral tied to EGC is worse. With no EGC the chassis does not become energized.

With that said, don't a lot of tools and appliances have the chassis tied to neutral internally? That would create the same problem.

AFAIK, except for dryers and ranges the UL does not allow a connection between neutral and exposed parts, even when hard wired or a polarized plug is used.
Unless double insulation methods are used most devices these days require an EGC connection.

 

[Jamesco]

In his scenario neutral tied to EGC is worse. With no EGC the chassis does not become energized.

With that said, don't a lot of tools and appliances have the chassis tied to neutral internally? That would create the same problem.

No! Never! The neutral is a current carrying conductor and should never be connected to the chassis.

 

[jaggedben]

No! Never! ...

Well your post contradicts Golddigger's somewhat. (And to be clear, I'm talking about factory connections, never an installer made one.)

I thought polarized two-prong plugs had something to do with grounding certain parts of the tool or appliance, but I suppose I probably have more to learn.

 

[Jamesco]

Well your post contradicts Golddigger's somewhat. (And to be clear, I'm talking about factory connections, never an installer made one.)

Many, many, many, years ago. A 4 wire cord and plug has been required for many, many, many, years.

I thought polarized two-prong plugs had something to do with grounding certain parts of the tool or appliance, but I suppose I probably have more to learn.

Tools with 2 wire cord and polarized plugs have internal double insulated power wiring. An EGC is not needed.



.

 

[GoldDigger]

Well your post contradicts Golddigger's somewhat. (And to be clear, I'm talking about factory connections, never an installer made one.)

I thought polarized two-prong plugs had something to do with grounding certain parts of the tool or appliance, but I suppose I probably have more to learn.

The easiest to understand use of polarized plugs is for floor and table lamps with Edison base (screw in) lamp sockets.
The polarized cord is an attempt to insure that the more exposed, especially during bulb changing, screw shell is connected to the neutral conductor. But the shell is still required to be insulated to some extent, even if only by cardboard.
Another justification is that the single pole switch is known to be interrupting the hot rather than the grounded conductor.

FWIW, the neutral to ground jumper in a washer or range often comes installed from the factory and the installer is instructed to remove it. If the appliance is later moved to a three wire connection the jumper can be reinstalled.

Sent from my XT1585 using Tapatalk

 

[LarryFine]

In addition, when the 3-wire major appliance circuit is/was permitted, it was a case of the neutral being used for grounding purposes, not the other way around. In addition, the neutral was to be insulated unless part of SE cable, and was to be supplied from the main panel, not a sub-panel.

 

[480sparky]

In his scenario neutral tied to EGC is worse. With no EGC the chassis does not become energized.

With that said, don't a lot of tools and appliances have the chassis tied to neutral internally? That would create the same problem.

I think you're referring to the exact opposite..... double insulated.... to make sure the exterior of an appliance doesn't come in contact with anything that's possible energized.

 

[jaggedben]

Many, many, many, years ago. A 4 wire cord and plug has been required for many, many, many, years.



Tools with 2 wire cord and polarized plugs have internal double insulated power wiring. An EGC is not needed.



.

The easiest to understand use of polarized plugs is for floor and table lamps with Edison base (screw in) lamp sockets.
The polarized cord is an attempt to insure that the more exposed, especially during bulb changing, screw shell is connected to the neutral conductor. But the shell is still required to be insulated to some extent, even if only by cardboard.
Another justification is that the single pole switch is known to be interrupting the hot rather than the grounded conductor.

FWIW, the neutral to ground jumper in a washer or range often comes installed from the factory and the installer is instructed to remove it. If the appliance is later moved to a three wire connection the jumper can be reinstalled.

So I had in mind power tools, not lamps. For example, my circular saw, palm sander, router, an rotohammer all have polarized 2-prong plugs. I suppose there's probably something to the design that makes one internal lead more worth being protected from than the other. Maybe the switch.

 

[LarryFine]

So I had in mind power tools, not lamps. For example, my circular saw, palm sander, router, an rotohammer all have polarized 2-prong plugs. I suppose there's probably something to the design that makes one internal lead more worth being protected from than the other. Maybe the switch.

No, except for possibly the switch, the polarity of the cord is not because the narrow prong is in any way connected to a "more insulated" wire than the other.