Electrical Wiring - Switch Hot Or Neutral?

[crokett]

Just wondering which way is the 'right' way. Finishing the wiring in the shop and hooking up the light switches. Power comes in to both of the switch boxes. In one box, the hot lead runs to the switches. In the other box the neutral ran to the switches. I rewired it to switch the hot because

a) that is what I've always done and what I will expect if I have to open the box again

b) the wires were backstabbed and I hate backstabbing

I know there is no real functional difference, but just wondered.

[mjernigan]

David--

While my degree is EE, I'm no electrician, but I'll jump in. Assuming you're talking a simple single pole single throw, one switch per device circuit: Switch the HOT, such that when the light is off, there is no power at the light. If you switch the neutral, then the light will be off--that is, extinguished--but there will be power to the recepticle.

I almost bit it this spring installing some flourescent lights in my garage where a previous owner switched the neutral. Had I assumed that because the switch was off there was no power there, I could have been killed. Luckily, I stuck with my habit of always testing even though I'd switched it off (though stupidly, not at the breaker), and heard the howling of the tester before I reached up to disconnect.

Mike

[Tom Slick]

Always switch neutral, it's a safety issue.


Edit: Disregard my above advice, it should be NEVER switch neutral. See my post below.

[jziegler]

Always switch neutral, it's a safety issue.

I thought it was the other way around. If you switch neutral, the socket is still hot when turned off, so you can still get zapped by it.

[BobSch]

Always switch neutral, it's a safety issue.

I disagree. As Mike said, if you switch the neutral the circuit is still HOT.

[os1kne]

I'll vote for switch the hot.

[chopnhack]

As far as I know, you always switch the hot. Just think about what it is you are "switching".... you are turning off the flow of electricity, when switching the neutral you are interupting the flow...there is a difference. When something grounds the interrupted flow, the flow resumes and more than likely shocks/kills you. Ground the switched hot when its off and ... nothing happens!

[krogers]

There was a wiring diagram in Family Handyman recently showing some simple electrical issues around the house. They showed switch the Neutral. I don't know the specific reason why. That is the way I have always seen it drawn.

[gjat]

I'm not an electrician, but I work for an electrical contractor, so my opinion is exactly equal to the fee you just paid me. (Which was NOTHING)

You switch the HOT. The Neutral is basically the same as a ground. If you were to fully investigate a household electrical system, you'd find the ground is connected to the neutral bar in the main panel. They're essentially the same thing.

For safety reasons, you want to eliminate the source of the power at the device, not the ground. For example, if you switch off a light, and go to work on the socket, the power would still be there, but seeking a source to ground. Whether it's the neutral or a ground, you body can physically make the connection from the hot, completing the circuit, and electrocuting yourself.

[Tom Slick]

Sorry guys, I meant to say NEVER switch neutral!!!! I have no idea why "always" came out instead. talk about giving the wrong response. Brain fart.

Always always always switch hot, it is a safety issue

[LCHIEN]

always switch the hot side. Since the neutral line is at or very near ground. Theoretically you can touch neutral or/or ground and not get shocked as long as the Hot is insulated or disconnected.

Think about it this way. You have an appliance box. Hot and neutral come into the box and the hot immediately goes into a switch. The other side of the switch controls several loads, timers, lights, heaters etc inside the eletrical box. If the switch is off then you can be standing in a puddle of water attached to ground and touch anything inside the box except the one point where the hot is connected to the switch and you'll be OK.
Now, if the neutral was switched only instead of the hot, then touching anything in the box and standing in the water you'll be severely shocked because the hot is everywhere, on every electrical component in the box.

Now imagine the room is the box....

[master53yoda]

I've commented on this before but people have died because of switching neutrals.

[jussi]

David--
, and heard the howling of the tester before I reached up to disconnect.

Mike

Are you talking about a non contact tester? If so, which brand/model do you use?

[os1kne]

I don't mean to hijack the question, but I have a pair of Gardner Bender Circuit Alert wirestrippers with the non-contact voltage sensor built into the handle. I have an older model than what's shown on the link and I bought mine on clearance because I needed a new pair of wirestrippers. I thought that the voltage sensor would be a neat feature that I wouldn't use much, but I use it often - and it's helped save my butt from making bad assumptions. They sell a stand-alone sensor as well. (Remember to turn it off to prevent draining the batteries.)

http://www.circuitalert.com/circuit_...strippers.html

[crokett]

I'm glad I rewired it. I knew about the issues with leaving it hot to the fixture but hadn't thought about the potential ground issues. I have a Gardner Bender non-contact voltage sensor, although not one that is built into the wire strippers. I should add that