house electrics question

[96terrano]

I'm curious to why all radiators, matal sinks etc are earthed In my house, and they aren't connected to a 240/250v supply

Why is this

[wildbri]

the earth wires are fitted to all metal surfaces so that that they are all bonded together as one. should an electrical equipment become faulty so that the metal surfaces could become live then the bonding to earth will cause a fuse to blow or a circuit breaker to trip so disconnecting the faulty fitting or cable from the mains. to put it simply TO STOP YOU GETTING ELECTRICUTED. regards bri

[96terrano]

Ahh right...... I see now, cheers I was just curious as I thought the sinks radiation system wad isolated form any electrical systems within in house

[rustic]

You will also find earth bonds between the hot and cold water taps on sinks and basins etc. but on older systems this was not done.
This is just in case that the hot water system becomes live say through an immersion heater fault and bad earth, thus giving 240 on one tap, and earth on the other.
Since most of us operate both taps at once... This could be lethal.

What really concerns me regarding plumbing, is that more and more people are using plastic pipes, and if used for modifications, could in fact insulate certain parts of the water system, thus loosing safety earths.

So think about safety when using plastic.

Your main earth in houses used to be either the metal water pipe or metal gas pipe, but since these are now often plastic, then the earth might come from the armoured cable near to the meter, or to an earth rod outside the building.

Never disconnect earths

Certainly RCD's or earth leakage trips help to prevent electrocution, however the lighting system is often not protected via RCD's so you are more at risk.
So treat with respect if working with lights especially in bathrooms and kitchens.
There are now a lot of legal issues regarding the extension and additional wiring added to domestic systems.
So seek advice before considering messing with wiring.

I have seen complete idiots replace wall sockets and light switches, and crossed over live and neutral, so it could have been worse, if they got the earth wrong.

This is made worse by the likes of Aldi and Lidl type places selling cheap metal clad switches and sockets, which the general public attempt to swap themselves.

If they get the earth wire wrong, and remember the lighting circuit may not have RCD protection, then this could leave the metal switch plate live.

Rant over for now...

Best regards,

Rustic

[davenclaire]

also you msin central heating pump is 240v as are your syncro motors if they go short and they can then the central heating pipes will go live to, bang big time if you touch a radiator. just recently had to rebond all my pipes and fit a new ground earth

[rustic]

Originally Posted by davenclaire

also you msin central heating pump is 240v as are your syncro motors if they go short and they can then the central heating pipes will go live to, bang big time if you touch a radiator. just recently had to rebond all my pipes and fit a new ground earth

We are talking 4 mm2 cable too, not cheap and nasty flex.

[solarman216]

Originally Posted by rustic

You will also find earth bonds between the hot and cold water taps on sinks and basins etc. but on older systems this was not done.
This is just in case that the hot water system becomes live say through an immersion heater fault and bad earth, thus giving 240 on one tap, and earth on the other.
Since most of us operate both taps at once... This could be lethal.

What really concerns me regarding plumbing, is that more and more people are using plastic pipes, and if used for modifications, could in fact insulate certain parts of the water system, thus loosing safety earths.

So think about safety when using plastic.

Your main earth in houses used to be either the metal water pipe or metal gas pipe, but since these are now often plastic, then the earth might come from the armoured cable near to the meter, or to an earth rod outside the building.

Never disconnect earths

Certainly RCD's or earth leakage trips help to prevent electrocution, however the lighting system is often not protected via RCD's so you are more at risk.
So treat with respect if working with lights especially in bathrooms and kitchens.
There are now a lot of legal issues regarding the extension and additional wiring added to domestic systems.
So seek advice before considering messing with wiring.

I have seen complete idiots replace wall sockets and light switches, and crossed over live and neutral, so it could have been worse, if they got the earth wrong.

This is made worse by the likes of Aldi and Lidl type places selling cheap metal clad switches and sockets, which the general public attempt to swap themselves.

If they get the earth wire wrong, and remember the lighting circuit may not have RCD protection, then this could leave the metal switch plate live.

Rant over for now...

Best regards,

Rustic

Well said mate specially about the introduction of plastic pipe for repairs, a little understood area, Rick

[rustic]

Originally Posted by solarman216

Well said mate specially about the introduction of plastic pipe for repairs, a little understood area, Rick

I would like to thank 96 Terrano for starting his thread,
as I hope it will make people more aware of the issues of messing with electricity, and more especially in areas that involve water.

[briggie]

in fact if you really want to be scared about mains electric ......

it is ac ... alternating current ..... ie ..... its 240 v ( rms ) positive , but also 240v ( rms ) negative voltage too , so you actually have a potential difference of 480v ( rms ) , the real potential difference is much more

[jims-terrano]

Originally Posted by briggie

in fact if you really want to be scared about mains electric ......

it is ac ... alternating current ..... ie ..... its 240 v ( rms ) positive , but also 240v ( rms ) negative voltage too , so you actually have a potential difference of 480v ( rms ) , the real potential difference is much more

Excuse me oh wise one, you are speaking like a ham

[briggie]

Originally Posted by jims-terrano

Excuse me oh wise one, you are speaking like a ham

rms ( root mean square ) is 70.7 % of the sum , so that needs to be taken into account when working it out ......... oops sorry jim

[96terrano]

Originally Posted by briggie

rms ( root mean square ) is 70.7 % of the sum , so that needs to be taken into account when working it out ......... oops sorry jim

Soo, what's the rms mean on a speaker, as an auto electrician I should know

[briggie]

Originally Posted by 96terrano

Soo, what's the rms mean on a speaker, as an auto electrician I should know

im sure jim will be more than happy to explain

[briggie]

rather than us trying to explain ......... use google

its easy really , just complicated to explain , especially for a old wrinkly like me lol

[96terrano]

Originally Posted by briggie

especially for a old wrinkly like me lol

I'm saying nowt