Two phases to house - loss of neutral

l and earth

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.

Reply to
nesesu
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mains

All new construction [last 30 years] around here uses iron mains with rubber sealed joints and plastic service pipe into all homes, so there is NO bond from the house to the main. The Gas main is plastic, as are the service drops. So, the only earth connection is the rather 'iffy' pair of 8' ground rods usually in the rain shadow of the roof overhang.

Neil S.

Reply to
nesesu

It would be across both sets, but......

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.

Reply to
terryc

That is true in a lot of cases, however I have noticed with a lot of newer houses, (in QLD anyway) they are using some kind of either black or grey pvc or poly pipe for home water mains. To make it worse, it looks to me to be "crimped" together at joins, sometimes with what look like soft metal rings but not always.

Copper or the old cast iron pipes would provide an excellent Earth, and excellent soil electrical contact due to the enormous surface area of the water main in contact with the soil over distance

Mine is all copper, all the way back to the water main, so no problems here.

Reply to
kreed

Having the breakers trip because a faulty neutral in an neighbours house (which would cause his neutral current to flow through his earth and your earth (etc) to the common neutral) could be an annoyance.

bye.

Reply to
Jasen Betts

**It's going to be a lot more popular too. The stuff is around half the price of copper pipes, is very easy to handle and use.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

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.

Reply to
Bruce Varley

Actually, the Neutral conductors are *NOT* connected to the plumbing system. The Neutral conductor is connected by the MEN link to the main earthing conductor, which is connected to the appropriate earth electrode. AS/NZS 3000 then requires that conductive pipe work be equipotentially bonded to the main earth conductor or earth terminal or bar (NOT to the neutral).

David

Reply to
David

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

Reply to
Meat Plow

I actually had the neutral fail (break) a few years back during a winter wind-storm. No deleterious effects. The imbalance (neutral) current was carried by the ground, a copper water pipe that's probably at least 10 feet below gound level and 20 0r so feet long.

Jerry

Reply to
Jerry Peters

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.
Reply to
Baron

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.
Reply to
Baron

Is this something new(

Reply to
terryc

"Phil Allison"

** 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

Reply to
Phil Allison

Sometimes, just to make things really exciting, some of the neutral current flows over alternate paths to a neighbor's house. These alternate paths can include things like cable TV shields.

Reply to
David Brodbeck

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.

Reply to
whit3rd

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.

Reply to
Sylvia Else

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

Sylvia.

Reply to
Sylvia Else

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

Reply to
Thomas Tornblom

**Depends on the equipment you connected. The damage might range from mild to catastrophic.
**Briefly, yes.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

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