Two MET's in a House?

[D80]

Was checking out a job for someone I do a bit of work for - he feels the gas installers are cutting corners with the electrics.

Amongst the several problems is the house now has 2 METS (existing is a TT system with no earth pit but to all intents and purposes has a main earth in there somewhere, new work has a new rod & pit).

The gas sparks have installed the new rod and also a new MET - but not linked to the existing MET.

So:
Gas bond, new board, Earth to Rod on one MET
Water bond, 2 existing boards,l existing main earth on another...

Didn't have my MFT with me, but no continuity between the two from my multimeter. Any ideas on which regs this contravenes?

 

[Deleted member 26818]

You can only have one MET.
What you are describing is essentially two EMTs with no MET.

 

[ezzzekiel]

if he is using the gas installers to do his electical work then any probs he has are his own fault.

 

[truckster]

542.4.1 says "in every installation a main earthing terminal shall be provided" Hence you can only have one Main Earthing Terminal

 

[Blowcat]

I would be inclined to establish where the main earth for the installation is coming from first and then arrange the earthing from there.
Failing that a link inbetween both earth blocks is what I might sugest.(and do)
or just a bigger earth block if they are local to each other

Sounds as though they are doing a half reasonable job except for the minor earthing and bonding failures. lets hope there no faults for the sake of the people there!!!

 

[B16 Tom]

Why are the gas men doing the electrical work??? If my car needs repairing i wouldnt take it to my hairdresser???
The MET can be joined together via a cable run. But you would need to make sure the Ze is satisfactory!! I have done this many times and find a 16mm cpc between the 2 works fine depending on the lenghth of the run. (If not the dreaded adiabatic eqaution is needed):hanged:

 

[Engineer54]

How come no-one is suggesting to make this situation Right?? ... ie, One MET, located at or near the DNOs cut out head, or the earth bar of the CU. Leaving this micky mouse set- up as is, ....is only going to cause future possible confusion and problems to homeowner and electricians alike!!

 

[Dcf]

Makes a change from having no earth, spoilt for choice eh?As the guy in highlander said ther can be only one.good old gas installers

 

[D80]

The Gas Sparks - they are the Sparks the gas installers use and are a NIC registered company.

 

[D80]

I can understand if my original terminology is a little bit off, but it paints the picture. One set of earthing at an esco, another some 6 inches away in an old consumer unit. They aren't linked other than through 2 separate earths.

 

[JLD]

How come no-one is suggesting to make this situation Right?? ... ie, One MET, located at or near the DNOs cut out head, or the earth bar of the CU. Leaving this micky mouse set- up as is, ....is only going to cause future possible confusion and problems to homeowner and electricians alike!!

My sentiments exactly. Just because a company is registered with NICEIC does not automatically make everything they do correct or even safe. Our industry is suffering because people put so much effort into finding work arounds rather than putting things right.