Is it safe touching the neutral wire of my design?

Thread Starter

Leon_Chan

Joined Sep 11, 2019
99
I want a device to be switched on outside the house with a switch. The device is connected to the ac source without the netural wire, it is a 2 legs plug. So is it safe to just left the earth wire to be outside the house with the on/off switch ( the live wire is completely placed inside the house)?

Also, can a home circuit breaker protect against electrical shock of device connected without a netural wire?

Any advice?
>>>>
The first time I keep it remembered in the school, E-L-N, was some 30 years ago. I have mistakenly the two earth and neutral wires. So sorry about this.

I rewrite the original question above as follows:-

I want a device to be switched on outside the house with a switch. The device is connected to the ac source without the earth wire, it is a 2 legs plug. So is it safe to just leave the neutral wire to be outside the house with the on/off switch ( the live wire is completely placed inside the house)?

In case this plan does not work, what would be the best ways to switch on the in-house device?
 
Last edited:

boostbuck

Joined Oct 5, 2017
501
If you have RCBs installed your installation will not work as the A-N current will be out of balance, causing the RCB to trip.

Advice: DONT. You should not use the earth as a current return.
Do it properly.
 

MrChips

Joined Oct 2, 2009
30,707
A circuit breaker is there not to protect against electrical shock but to prevent burning down your house.
To protect against electrical shock you need a GFCI. For this to work you need all three wires, LINE, NEUTRAL, EARTH.
 

wayneh

Joined Sep 9, 2010
17,496
I want a device to be switched on outside the house with a switch. The device is connected to the ac source without the netural wire, it is a 2 legs plug. So is it safe to just left the earth wire to be outside the house with the on/off switch ( the live wire is completely placed inside the house)?

Also, can a home circuit breaker protect against electrical shock of device connected without a netural wire?

Any advice?
Circuit breakers do not protect against shock. They protect the wiring in your house to prevent a fire caused by excessive current.

A GFCI helps protect against shock by comparing the current in the line wire with that in the neutral. If they are not very nearly equal, that means some current is leaking to ground in some path other than the neutral wire. That other path might be you, so the GFCI will trip. You obviously have no such protection in your scenario.

It’s not clear to me where your current is going. I understand the hot side but where is the path to ground?

And I agree this sounds unsafe.
 

SamR

Joined Mar 19, 2019
5,031
Why would there be a hot leg and not a neutral? That is a huge error to start with and it should be remedied, not compounded. And, as Mr. Chips said, do it correctly and not haphazardly. Install a hot, neutral, safety ground, and GFCI component.
 

Thread Starter

Leon_Chan

Joined Sep 11, 2019
99
Device, like hair dryer, does not come with a netural wire as it is enclosed inside a plastic case. Also, most devices made, may be for example from China , may not come with the netural wire.

So what would be the best ways to made available an on/off switch outside the house and prevent people from getting a shock?
 

boostbuck

Joined Oct 5, 2017
501
Double Insulated devices with only two pins lack an EARTH wire, not a neutral wire.

For your own safety's sake, I suggest you employ a professional for this job.
 

SamR

Joined Mar 19, 2019
5,031
If it doesn't have a neutral, then there is no circuit. There isn't a single prong on the plug for a reason. It has to have at least 2 prongs connected to the outlet to make a circuit, Hot and Neutral! A supply path to the load and a return path. The fact that the Neutral is eventually connected to the earth ground the same as the safety ground does not mean that they serve the same purpose.
 

MrChips

Joined Oct 2, 2009
30,707
Device, like hair dryer, does not come with a netural wire as it is enclosed inside a plastic case. Also, most devices made, may be for example from China , may not come with the netural wire.

So what would be the best ways to made available an on/off switch outside the house and prevent people from getting a shock?
You are confusing EARTH and NEUTRAL.
All two-prong appliances use LINE and NEUTRAL.

We have said it before. You need a GFCI with all three wires connected.
 

Thread Starter

Leon_Chan

Joined Sep 11, 2019
99
The first time I keep it remembered in the school, E-L-N, was some 30 years ago. I have mistakenly the two earth and neutral wires. So sorry about this.

I rewrite the original question as follows:-

I want a device to be switched on outside the house with a switch. The device is connected to the ac source without the earth wire, it is a 2 legs plug. So is it safe to just leave the neutral wire to be outside the house with the on/off switch ( the live wire is completely placed inside the house)?

In case this plan does not work, what would be the best ways to switch on the in-house device?
 
To protect against electrical shock you need a GFCI. For this to work you need all three wires, LINE, NEUTRAL, EARTH.
Earth is not required for a GFCI to work. In fact in the US, you can have a GFCI (3-wire receptacle) on a 2-wire circuit as log as it's labeled "No equipment ground".

i have had a post lamp for years, no GFCI. In fact there are no breakers in the house. Just fuses.
The outdoor circuits for the porch and outside front receptacle are protected with a GFCI receptacle and all downstream devices. The light over the front door isn't protected either.

The stupid people would let a hair dryer fall into the sink or bathtub. The bathroom could get a nubber of GFCI outllets all in the same place.

Outside devices like hedge trimmers that can cut the cord, I NEED a GFCI.

I really don't care about the bathroom either. Two inductive electric toothbrush chargers and one inductive Airfloss. One charger for a beard trimmer. Low voltage plug in wall wart. Wall Wart is left plugged in. Hair dryer has an integral GFCI..

It would be "NICE" to put real outlets there.

Pretty much grandfathered.

Aside: (which I might write up)
I mounted what would be a legal use of a Medical grade Outlet strip on a Hospital bed in Patient Areas.
It's mounted and it requires tools, so I'm cool. I'm not in a medical facility, anyway.
I just got tired of plugging in the sweeper or hair dryer every once in a while.
A charger for a medical device every 10 days for a few hours and a shelf to place it on. A nebulizer.

There's other stuff, but that's what the strip has. I'm going to mount a surge supresssor strip to the bed too and daisy chain strips. That won't comply. There is this general feeling that extension cords should not be permanent.
 

SamR

Joined Mar 19, 2019
5,031
If I remember my NEC correctly, for residential new construction, GFI is required for A) Any outlet within 6 feet of a water outlet. This covers baths, laundry sinks and kitchens. B) Outlets within an enclosed garage are. For fuel fumes. C) Outdoor receptacles. To protect from water and protect extension cords. Also required is 3 wire circuit construction.
My GFIs were installed in the panel as breakers. There weren't any GFI receptacles back then and it's a long walk from one end of the house and through a crowded garage and workroom to get to the master panel where they are installed.
There is always the "grandfather clause", but the prudent approach is to treat any electrical work as new construction where possible.
They also now make plugin GFIs. The one that I have plugs into a single 3 prong receptacle outlet and provides dual GFI protected outlets.
 
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wayneh

Joined Sep 9, 2010
17,496
Where I live (northern Illinois), new installations require an arc fault circuit interrupter, AFCI. It's a notch up in expense over GFCI.
 

MrChips

Joined Oct 2, 2009
30,707
I don't know anything about 2-wire GFCI.

What I do know is that when we moved into our new house the GFCI in the service panel would trip as soon as I plugged in the data cable between my computer and the printer. After some very intensive investigation here is what I discovered.

1) The computer and the printer were plugged into two separate circuits. One circuit was serviced by a GFCI and the other had none. By connecting the printer cable I was completing the EARTH connection.

2) I traced the fault to a short between NEUTRAL and EARTH behind an outlet in a different part of the house. How did I diagnose this fault?
With the main breaker off, I had to do a binary search through the entire house wiring looking for a short between NEUTRAL and EARTH.

3) The EARTH wire to the GFCI was clipped at the service panel.

Here is the likely scenario that I have concluded. When the "certified" electrical installer closed the main circuit breaker for the first power-on test the GFCI tripped. It was too close to quitting time for the day. Rather than fix the problem, cutting the EARTH wire at the GFCI was the "quick fix".

Go figure!
 

wayneh

Joined Sep 9, 2010
17,496
Simply put,
the device is inside the house as well as the live wire
the switch and the neutral wire is outside the house
That's unsafe. The neutral wire leaving the device and heading to the switch is actually "hot" when the switch is off. If you use black wire to indicate this, that helps, but is misleading because it's not really a line wire.

And then there's the issue of someone or something outside flipping the switch. Depending what the device is, that could be dangerous.
 

MrChips

Joined Oct 2, 2009
30,707
There is nothing safe about touching any mains wiring.

If you want to disconnect power to the outside use a double pole switch and switch both lines.
You never know who installed the wires. Occasionally NEUTRAL and LINE have been found to be reversed.
 

DickCappels

Joined Aug 21, 2008
10,153
I updated the title
from :
Is it safe touching the earth wire?

to:
Is it safe touching the neutral wire of my design?
No, that is what the earth connection is for and why appliance frames and enclosures are connected to earth rather than neutral. A lot of thought went into this system.

In places I have lived there is the Hot or Line wire, a Neutral wire that is connected to ground at only one place in the system, and an Earth wire that is used for protective shields (grounding for your refrigerator, in my present case) and should not carry load current, otherwise it would become unsafe as is Neutral.
 
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