Electricity supply

[davidwi]

Just a quick one today - for a house (domestic) supply - what wire(s) come into the house from the street?

Is it 3 ie Live, Neutral, Earth?
Is it 2 ie Live, Neutral?
Is it 1 Live?

Thanks
D

 

[westie101]

In the majority of cases either: -

Live & Combined Neutral/Earth can be a single cable or 2 separate cables.
or
Live, Neutral & Earth (this if a PVC cable is in effect 3 wires, if a lead sheath it is two wires in the cable and the sheath as earth.

 

[ban-all-sheds]

Why do you need to know?

What are you planning to do with the information?

 

[davidwi]

Thanks Westie

I live in a Victorian Terrace so I expect then the cable coming in from the road will be the twin live and neutral with my Earth from a spike inside the house near my consumer unit

 

[davidwi]

Why do you need to know?

What are you planning to do with the information?

It is just to answer a general question.

I had thought only live came from the street with Earth and Neutral being brought from a spike near the consumer unit.

 

[westie101]

I live in a Victorian Terrace so I expect then the cable coming in from the road will be the twin live and neutral with my Earth from a spike inside the house near my consumer unit

Take and post a photo of the meter position and the incoming cable, I'm sure we can give a better answer if you do

 

[ban-all-sheds]

It is just to answer a general question.

But why?

Why are you asking - it can't be because of any existing interest in electrical matters.

And I sincerely hope it's not because you think you need to know in order to do any work:

I had thought only live came from the street with Earth and Neutral being brought from a spike near the consumer unit.

 

[davidwi]

It is just to answer a general question.

But why?

Why are you asking - it can't be because of any existing interest in electrical matters.

And I sincerely hope it's not because you think you need to know in order to do any work:

I had thought only live came from the street with Earth and Neutral being brought from a spike near the consumer unit.

Dear Ban-all-sheds
I merely have an inquisitive mind and an interest in all things scientific and this week, electrical supply has captured a few minutes of my time. I am not planning any work, nor do I imagine I need to have this information to enable me to carry out any DiY - purely interest. I hadn't realise the pylons across the countryside carry Live AND Neutral, that's all.

 

[westie101]

purely interest. I hadn't realise the pylons across the countryside carry Live AND Neutral, that's all.

Er they don't, the only time a neutral appears on electricity networks in this country is on the Low Voltage (230/400V) network.
Normally a pylon carries two 3 phase circuits both made up of 3 live conductors with the phases being 120deg apart

 

[Chri5]

This should clarify the exact system you have

http://www.diynot.com/wiki/electrics:earthing_supply_types_and_bonding:earthing_arrangements

 

[bernardgreen]

purely interest. I hadn't realise the pylons across the countryside carry Live AND Neutral, that's all.

Unfortunately 95% of pylons do not carry the neutral but do carry three live phases at 32,000 volts or higher. At substations two of these phases are fed to the inputs of a transformer which produces the 230 volts for domestic supplies on its output. One side of that output is the live to your house and the other side is the neutral to your house. At the substation the neutral is connected to ground.

That is the simple explanation. It is more complex in reality as the transformer may produce 3 lives at 230 volt in a three phase network which most are.

 

[davidwi]

This should clarify the exact system you have

http://www.diynot.com/wiki/electrics:earthing_supply_types_and_bonding:earthing_arrangements

Superb - thank you

 

[davidwi]

purely interest. I hadn't realise the pylons across the countryside carry Live AND Neutral, that's all.

Unfortunately 95% of pylons do not carry the neutral but do carry three live phases at 32,000 volts or higher. At substations two of these phases are fed to the inputs of a transformer which produces the 230 volts for domestic supplies on its output. One side of that output is the live to your house and the other side is the neutral to your house. At the substation the neutral is connected to ground.

That is the simple explanation. It is more complex in reality as the transformer may produce 3 lives at 230 volt in a three phase network which most are.

Thank you

 

[JohnD]

Thanks Westie

I live in a Victorian Terrace so I expect then the cable coming in from the road will be the twin live and neutral with my Earth from a spike inside the house near my consumer unit

Sometimes in an old terraced house there is a cable looping from your service head into the house next door, or vice-versa.

Sometimes there is no proper earth at all

As electricity supplies were (almost) never run into Victorian homes, we know your installation will be newer, and may have been upgraded once or more, so it might be quite modern; or it might not. Very hard to say without seeing it.