Shocking!

[Guest123]

Anyone else think it's probably a TN-C-S supply???


BBC News - Electricity cut to Ludlow homes after 'shock from tap'

 

[rocker]

Definite TNCS with external reversed polarity.

 

[Jimmy Boy]

Enlighten me guys how/why and how often does this occur.

Would an RCD have a hissy fit and trip if this happened ?

 

[Darkwood]

Broken neutral external on supply, one of the biggest risks with TNCS as all the earth in the houses then becomes a substitute path back, the house in question probably had insufficient bonding and used the owner to bridge the gap from radiator to ground, i noticed the diggers were out in the street and the power cut on purpose they would only do this after investigating the property installation, but they mention they fault could be within the property to sweeten the issue.
Well i say Neutral but its combined with Earth as well so hence the supply is earthed at multiple point throughout its length, this above fault can only really happen if the break is between the property and before the next multiple earth point thus the digger is so close to property.

 

[Sintra]

Why in the UK do we not fit an additional earth electrode onto a TNC-S system like some other european countries do to minimise the hazards of of broken supply neutral.

Any thoughts please gents.

 

[Darkwood]

It could also be a TNS as i bare witness to this, mentioned in other posts, if the earth armour corrodes and earth is lost you can get a similar situation but the installation needs to be in a L to E fault situation for the same result.

 

[Des 56]

Why in the UK do we not fit an additional earth electrode onto a TNC-S system like some other european countries do to minimise the hazards of of broken supply neutral.

Any thoughts please gents.

Open supply neutral located before the street location.
Street has non conducting water and gas sevices
Good protective bonding and an additional earth electrode in a single dwelling in a street, all off the same supply
The rest of the streets houses have no earth electrode

Streets return path is severed,both by the open neutral and by non conducting services
Nice house with earth electrode now becomes return path via its electrode for all Sunday dinners being cooked,cable overheats,catches fire and burns down well protected house and leaves others unscathed
As the faces would sing "All or nothing"

 

[malcolmsanford]

Why in the UK do we not fit an additional earth electrode onto a TNC-S system like some other european countries do to minimise the hazards of of broken supply neutral.

Any thoughts please gents.

Most Main supplies in Europe have a main RCD installed on the supply which is why they are not overly concerned with this or earthing in general. If you lost the neutral you would get that imbalance and the RCD will trip out.

Also what benefit would there be if you had a local stake, the eartrh faults would just use that as well, as often can happen in a TT system. PME is just a glorified TT system really. If you banged in enough rods you would reduce your Ze all the time.

That house most likely never had good bonding.

 

[gaz101]

Had similar problem last month
Western power did not bleave me till I put a temp e rod in lawn switched off main sw
Met to temp rod 125v
Corroded joint on pole