water zero or not

[the pict]

I remembered something today when discussing bonding some time back, the conversation went like this, most new builds and refurbs have the water supply in blue pipe alcathene so in theory no 0 potential introduced but as someone pointed out
when you open a tap zero potential goes down the plughole, literally, now I dont know how conductive water is but we are all well aware of the reduced resistivity it causes to people immersed in the stuff, comments anyone.
Pict

 

[Des 56]

I remembered something today when discussing bonding some time back, the conversation went like this, most new builds and refurbs have the water supply in blue pipe alcathene so in theory no 0 potential introduced but as someone pointed out
when you open a tap zero potential goes down the plughole, literally, now I dont know how conductive water is but we are all well aware of the reduced resistivity it causes to people immersed in the stuff, comments anyone.
Pict

Water is an insulator,think of a lead acid battery,it needs the sulphuric acid for the distilled water to conduct
Its only the impurites in the tap water that can help it become a conductor

Here is some technical bumph

Pure water contains equal numbers of H ions and OH ions. Less than one atom per million is ionized, so it is a poor conductor. Electrolytes which increase the number of H ions and decrease the number of OH ions are acids, and electrolytes which increase OH and decrease H are bases.

The total number of H ions times the total number of OH ions is constant (10^-14 of all the atons), so the greater the imbalance, the greater the number of ions, and therefore the greater the conductivity. So water with a pH of 7 (neutral) is a poor conductor, and water with a pH less than 5 or greater than 9 is a strong conductor.

 

[RogertheBodger]

Water is an insulator,think of a lead acid battery,it needs the sulphuric acid for the distilled water to conduct
Its only the impurites in the tap water that can help it become a conductor

Here is some technical bumph

Pure water contains equal numbers of H ions and OH ions. Less than one atom per million is ionized, so it is a poor conductor. Electrolytes which increase the number of H ions and decrease the number of OH ions are acids, and electrolytes which increase OH and decrease H are bases.

The total number of H ions times the total number of OH ions is constant (10^-14 of all the atons), so the greater the imbalance, the greater the number of ions, and therefore the greater the conductivity. So water with a pH of 7 (neutral) is a poor conductor, and water with a pH less than 5 or greater than 9 is a strong conductor.

Great answer professor Des.

What on earth have we got swirling around in our pipes? Just goes to show that old W.C.Fields was right - "Don't drink water, fishes make love in it"

On a more serious note Picts question is an interesting one, copper domestic water installation with a section of plastic pipe in it.

Is the water providing continuity between the sections of pipe, or is it insulating?

 

[Spudnik]

Only 100% pure water is an insulator.

The rubbish you have delivered to your home via pipes is not, due to the impurities it collects on its way.

 

[Goody]

Picked up this from a site:

"[SIZE=-1]Another phenomena that can happen once you try to expose water to a high electric potential is that it starts ionizing, i.e. you start creating ions in the water just from the strong electric field. Then you might end up with an ion trail being created, very much like the one created in the air during lightning, where the conductivity becomes very high. This trail becomes the passage for the current with almost no resistance.

In any case avoid electricity around wet things."[/SIZE]

 

[Deleted member 26818]

Tap water has a very low conductivity.
Whereas the water in central heating pipes, can have a high conductivity due to the additives that are sometimes added.

 

[Marvo]

Water is a reliable enough conductor to be a hazard when in proximity to electricity. On the other hand it's an unreliable enough conductor that it shouldn't be relied upon to provide earth continuity.

 

[IQ Electrical]

Water is a reliable enough conductor to be a hazard when in proximity to electricity. On the other hand it's an unreliable enough conductor that it shouldn't be relied upon to provide earth continuity.

Here's a bit of relevant reading:

 

[Engineer54]

They use deionized water for jet washing HV/MV cable insulators on say, ...distribution pylons and the like. I wouldn't fancy the operators chances, ...aiming tap water at those insulators!!!

 

[MarkieSparkie]

From my experiments, tap water in Weymouth, Dorset (hard water area), contained in a 1m long, 15mm plastic pipe has an impedance of about 80K ohms/m, meaning if 230Vac is applied a current of approximately 3mA/m flows. You may like to carry out experiments in your area.

 

[truckster]

From my experiments, tap water in Weymouth, Dorset (hard water area), contained in a 1m long, 15mm plastic pipe has an impedance of about 80K ohms/m, meaning if 230Vac is applied a current of approximately 3mA/m flows. You may like to carry out experiments in your area.

Don't they have television where you live?

 

[IQ Electrical]

Don't they have television where you live?

Well excuse me truckster matey, are you telling me you don't check your tap water resistivity on a regular basis?

I know I certainly do and I'm not sad!

I'll get my coat then......

 

[truckster]

OK I'll do it while the wifes in the bath, now do I test at 500V or a thousand?

 

[richy3333]

I just tried testing mine and now my Megger wont float anymore

 

[IQ Electrical]

I just tried testing mine and now my Megger wont float anymore

That's why you test for leakage first...