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Posted By: Uppeydog Lighting circuit Neutral - 11/21/05 10:09 PM
Brain Teaser (well it is for me!):

Cieling rose; Switched Live To Earth or Neutral = 240V..OK.

1st Neutral Black To Earth = 0V..OK.

Another Black 2nd(Supossed Neutral)Joined to 1st Neutral. When separated from 1st Neutral reads To earth = 240V...?
and to Switched Live (on) 0V.

When joind back to 1st Neutral reads To Switched Live = 240V. and to earth 0V.

Howcome This supposed Neutral carries 240V when separated from other Neutral?

Don't shout at me this for my neighbour!!
Posted By: aussie240 Re: Lighting circuit Neutral - 11/21/05 11:17 PM
Hard to visualise without a diagram....what is this other '240v neutral' connected to?
Are you using a high impedance digital voltmeter? If so the capacitance from this neutral to an active wire could be high enough to produce 240v on no load....especially if the neutral is part of a long length of twin cable.
If this '240v neutral' is the return for some other load which is switched on then obvioulsy it will be at 240v when disconnected.
Posted By: Uppeydog Re: Lighting circuit Neutral - 11/21/05 11:47 PM
Good one Aussie,
He's just knocked on my door, as someone tried to nick his cherry picker!!

He told me he's got it sorted; it was the neutral from the room next door. He had the switch next door taped down in the off position, but his offsider turned it on at the back door!!!(Two - Way Switched!!!)

I won't tell him you called him a stupid "POME B"... ('Cause he's 6'4"!!!)

Cheers. 2Rivers (Katherine & South Aligator)
Posted By: Trumpy Re: Lighting circuit Neutral - 11/23/05 04:16 AM
This particular thing has been known to kill the odd Electrician working at a switch-board.
If a Neutral loses its reference to it's usual busbar, it then becomes a Phase conductor.
This is of course assuming that the circuit is still energised and the switch is on.
Leaning you arm up against the metal side of a switch-board body and holding a wire you thought was a Neutral before can be the easy way to get a fatal hand-to-hand shock. [Linked Image]
Be careful around them Neutrals!.
Posted By: Texas_Ranger Re: Lighting circuit Neutral - 11/23/05 09:51 PM
That's why I like our 1+N circuit breakers so much!!! You can't switch off the phase w/o the neutral.
Posted By: Uppeydog Re: Lighting circuit Neutral - 11/25/05 09:28 AM
Thanks for those replies!

What had happened is the cieling had come down. Jim rang me & explianed the above.

The first thing I said was to turn off the lighting circuit & use table lamps plugged into the wall sockets for light.

So they obviously just turned off the light switches & taped them down. Not awear the kitchen fluro was double-switched !! Meanwhile his mate had come in the back door, turned on the fluro (which did not light because the neutral loop was disconnected in the next room)so he probably left it on, which energised the open neutral in the next room!!
At least they were awear of the "live" conductor.

Just goes to show the juction box set up is a lot safer in these situations, where the loop remains intact, & just each fitting can be removed (with the supply off of course!) but you never know what's happened in the past ie. some one may have decided to connect in a neutral from a different circuit. (Good old multimeter saves the day again!!)

Texas Ranger: are they (L+N) the standard cicuit breakers in USA?

Cheers, 2Rivers.
Posted By: pauluk Re: Lighting circuit Neutral - 11/25/05 10:35 AM
People sometimes don't seem to realize that the neutral is only at (or near) ground potential so long as it is connected to the supply neutral. As soon as there's a break..... [Linked Image]

Quote
are they (L+N) the standard cicuit breakers in USA?

No, the U.S. normally just switches the phase(s), as here. Even the main on a panel doesn't open the neutral. Texas-Ranger is in Austria.
Posted By: Texas_Ranger Re: Lighting circuit Neutral - 11/26/05 04:39 PM
Quote
Texas Ranger: are they (L+N) the standard cicuit breakers in USA?
As far as I'm aware of 1+N breakers are only commonly used in Austria, France, Belgium and some Eastern European countries.

Re: my nick: we got international TV here too [Linked Image]
Posted By: pauluk Re: Lighting circuit Neutral - 11/26/05 04:47 PM
So there's no truth to the ECN rumor that you're related to one of these guys then, kemo-sabe? [Linked Image]

[Linked Image from lonerangerfanclub.com]


[This message has been edited by pauluk (edited 11-26-2005).]
Posted By: Texas_Ranger Re: Lighting circuit Neutral - 11/26/05 11:55 PM
My nick name is my only connection to them... [Linked Image]
Posted By: Uppeydog Re: Lighting circuit Neutral - 11/29/05 12:55 PM
That's the best laugh I've had in days!!

I'm upto my neck here in a family bereavement....Don't panic Paul it's nothing to do with that Neutral!!!

From,
Kiwi...(I'm from Reykjavik!)

[This message has been edited by Uppeydog (edited 11-29-2005).]
Posted By: Uppeydog Re: Lighting circuit Neutral - 11/29/05 01:55 PM
You blokes are getting me in a lot of strife!...I'm walking around here with a tear in my eye, but it's coupled with a stupid grin!!!
I'm just waiting on my brother & sister-in-law from Toronto Canada to land at Glasgow airport.
His name is: Afghan-Rebel!
& Her name is: Zanzibar-Sue!
OH No...Here we go again!! TOO FAR!!!
Posted By: Alan Belson Re: Lighting circuit Neutral - 11/29/05 07:18 PM
All the goodies ( ie kimusaby ) wore white hats. The bad guys all had black hats. When he shot the bad guys, it was always to knock a gun out of their hands. From 100 yards. With a revolver (!), which in real life would literally have been filed inaccurately out of a solid billet and which would have been hard-pressed to hit a barn. From the inside. Without all the rounds going off at once and blowing his head off. Using shells 20 years before they were invented. And if he'd really worn those ridiculo gloves in that heat, his hands would have rotted off!! The mask!! What a larf!! - "Yoo-Hoo, Clayton! What's that on your face!?" The token Native American played by an Anglo-Saxon. But I loved every second of it!
Only problem is, that's the 'Lone Ranger', and 'Tonto'. The actual 'Texas Rangers' are much respected officers of the law.
Posted By: pauluk Re: Lighting circuit Neutral - 12/01/05 04:42 PM
It's been a few years, but didn't the Lone Ranger start out as one of the Texas Rangers? I seem to remember an episode explaining how he came to be out on his own......

Totally off-topic, but re the white hats I have a tape full of old car commercials from the 50s/60s here. One of them is a cartoon-type ad for Dodge pickup trucks:

"Get on down to the Dodge Boys today. You can tell they're good guys -- They all wear white hats!" [Linked Image]
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