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Re: Two phases to house - loss of neutral



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Except where plastic is in use.  Mine is all plastic and the safety
earth is linked to the armouring on the incoming mains feed cable.

--
Best Regards:
                     Baron.

Re: Two phases to house - loss of neutral




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Is this something new(<40 yrs) in the Standards in Australia?
No plumbing link here. Just an earth stake under the box.

Re: Two phases to house - loss of neutral



"Phil Allison"
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** If that situation arose it would be possible to break the flats into
three groups and feed each group with their own phase and neutral conductor.



....  Phil





Re: Two phases to house - loss of neutral


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**Not an issue, due to the MEN system used in AUSTRALIA. Cross-posting to an
international group will guarantee a bunch of useless comments. Pay
attention to Australian posters only.

Your electrician is correct.


--
Trevor Wilson
www.rageaudio.com.au



Re: Two phases to house - loss of neutral


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 From the replies, the same system applies in the US. But people have
still had problems.

Sylvia.

Re: Two phases to house - loss of neutral


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**AFAIK, the US system is fundamentally different to ours.


--
Trevor Wilson
www.rageaudio.com.au



Re: Two phases to house - loss of neutral



"Trevor Wilson"

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** In the US and Canada  -   it is  NOT  permitted to link neutral and earth
or plumbing within a premises.

See here under the heading "Regulations".

http://en.wikipedia.org/wiki/Earthing_system

The MEN system used here in Australia seems to be unique.

See last para on same page.


.....  Phil



Re: Two phases to house - loss of neutral


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**Interesting. I'd have thunk that some places in Europe might employ a
similar system. Guess not. Ever since I ran across my first US audio product
with a high value resistor to chassis from (allegedly) Neutral, I realised
that the US system was highly flawed.


--
Trevor Wilson
www.rageaudio.com.au



Re: Two phases to house - loss of neutral


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Rubbish. In most of Canada, it is manditory that the neutral be bonded
to earth at only ONE point, the service entrance switch enclosure.
From that point an earth conductor is connected to 2 ground rods and
to any metallic piping system(s).
Neutral failure is a not uncommon problem especially with overhead
aluminum 'triplex' service drops. A seagull deficates on the bare
aluminum neutral and it soon rots off leaving an open neutral
condition.
Ground rod to earth resistances of 5 ohms are not uncommon, so a 10A
unbalance between 'phases' could give a 50V offset of the neutral.

Neil S.

Re: Two phases to house - loss of neutral



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Sylvia

Thought one. Get rid of the electrician.

In my experience with loss of neutrals it is the number one cause of
electrical equipment/lighting failure.

Bob  AZ

Re: Two phases to house - loss of neutral


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not a neutral problem but.
I can remember an old lady complaining that every time she turned the
hot water tap the lights came on half brilliance.and sure enough they did.
she had three phase and an instantaneous three phase water heater.

one phase had gone and the heater caused the dead phase to be live in
series with element.(the water flow closes the heater circuit)

Re: Two phases to house - loss of neutral



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It would be across both sets, but......
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The neutral is actually grounded to the earth for such a case; hence MEN
(Multiple Earth Neutral), so the neutral would actually travel through
the ground to your neighbours earth stake and back into the neutral phase
there.

If the USA Godzilla remake is to be believed, all your earth worms will
come to the surface as an indicator, (or is that only for correct DC
connections?).

If you are worried about such an event happening, dump a bucket of wter
on your earth stake quarterly and encourage your neighbours to do the
same.


Re: Two phases to house - loss of neutral



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It actually happened in our house about 2 weeks ago, an overgrown bush near
the incomer was the cause. First sign of trouble was unexpected swings in
light brightness when kitchen appliances were switched on. I checked with a
DVM, and saw phase voltages to neutral shifting between 275 volts (240
nominal) and 190 volts as appliances were turned on and off. Perhaps
fortunately, at the time we didn't have any electronics energised. There was
no equipment damage at all.



Re: Two phases to house - loss of neutral


On Tue, 24 Nov 2009 11:10:26 +1100, Sylvia Else

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Removing the return leg isn't going to cause problems in a properly
wired US home. Don't know about the UK.

Re: Two phases to house - loss of neutral



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The lights would go out !  Domestic properties usually have just a 240v
single phase feed.  Usually you would get a single phase running down
one side of the street and another phase running down the other.

--
Best Regards:
                     Baron.

Re: Two phases to house - loss of neutral



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That's just false.  A properly wired US home without a neutral
wire to the transformer has 240V across both phases, which
can leave either phase anywhere from zero to 240 VAC.  Damage
to 120V appliances will result unless the breakers trip first.

The 'ground' connection would have to carry the whole house's
current imbalance load in place of that neutral, through the earth to
some nearby dwelling that DOES have a proper neutral wire,
to the same pole-pig transformer, for this calamity not to occur.

Re: Two phases to house - loss of neutral


Leaving the neutral failure issue aside, what would happen if I disabled
the Earth leakage detectors and drew power across the two phases.

Would the two utility meters correctly reflect the energy I consumed?

Sylvia.

Re: Two phases to house - loss of neutral


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On second thoughts, it's pretty obvious that they wouldn't be correct,
and that I'd be significantly overcharged for the power.

Sylvia.

Re: Two phases to house - loss of neutral



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yes.


No you wouldn't.

Each of the meters will indicate what you draw from the phases, and as
you now have a higher voltage, you will also draw more power, which is
what you are paying for.

Thomas

Re: Two phases to house - loss of neutral



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**Depends on the equipment you connected. The damage might range from mild
to catastrophic.

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**Briefly, yes.


--
Trevor Wilson
www.rageaudio.com.au



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