Earthing a church

[colin durning]

Hi all,
I had been asked to look at the flourys in a church hall as they have problems getting new lamps.
When testing earth cont.(mettalic fittings) i detected 137v between fitting and MET.
I stopped there and inspected the system, free of charge of course, and found 2 100A supplies, 4 sub DB's, 2 water and 2 gas supplies. No bonding whatsoever,only 1 main earthing conductor that feeds 1 sub DB.

I have advised them to get it earthed pronto and they would like me to give quote.

Would it be acceptable to run the bonding to a sub DB, or will i have to run them to the SOURCE???
Not sure if a sub DB is regarded as the source.
Will i have to run main earthing conductors to each sub DB.

Any help would be much appreciated

 

[colin durning]

http://i1088.photobucket.com/albums/i332/dubf8t/utf-8BSU1HMDA3MjUtMjAxMTA0MjEtMTMyOC5qcGc.jpg

 

[colin durning]

Had a look at the last Periodic from 7 years ago, numerous Code1+2's. Several circuits with IR under 1Meg. VIR everywhere. It's a pity THE big man's skint

 

[Engineer54]

Thanks for the snaps, but too late for me to study ..... I'm sure you'll get some help here from others like Malcolm before i get back here tomorrow...

One of those service heads, is as old as that church, never seen one quite like that, looks as if there's something missing!!!! ...lol!!!

 

[colin durning]

Cheers.
Was thinking of ringing the DNO. You would like to think they would do summit with that.

 

[malcolmsanford]

That does not look like a quick tidy up job and walk away I think you have a bit of work there old mate.

Safety as got to be your first concern and that is the earthing and bonding. I would take a few more pictures and put togehter a plan for the church.

Highlight

The age of the header and advise that the DNO should be contacted. Personally I would be telling the DNO that you can sometimes smell burning and that there is sometimes a buzzing coming from the head, there is a good chance that will be a free upgrade on something that old.

The head at the belfry, is it redundant? it looks to me as if those carriers are empty?

That meter with all those tails .................that is a pure work of dedication getting all that lot in, I bet a few of those conductors have had a shave. If it were me I would when the DNO came to change the head take all that that lot out and fit say 25/35mm one set of tails. Now you could utilise that 3 phase grey board as it still looks ok but big and bulky, If there was money in the pot I would be looking at getting a nice 3 way ryefield to fit.

Once that is sorted again you will have to change the T+E to the sub boards. Personally I would not re-run T+E me I would use MICC, but again it's money, so SWA or even singles in some Plastic trunking. So from the Ryefield/existing board a sub mains 10/16mm depending on calcs to the sub boards.

That should sort out the earthing troubles. Me I would be fitting a 8 way MET at the origin there. The system looks like a TN-s, when the DNO upgrade they may fit a TNC-S for you. So whichever a 16mm main earth from the head to the MET. Then a 16mm from the MET to your Ryefield, and of course then onto your sub boards.

Bonding then you can sort out as you go.

That would be my suggestions to the church board. I reckon also they will have to get the local Building office involved as it may be listed, and then there is the Diocise which may want a say. I think your going to have to stress the safety issue and cover this in writing, you know how boards and comitees love a written missive.

 

[Engineer54]

Looking back over these photo's i think that Malcolm has got it spot on, especially the point that this isn't going to be a walk in the park job!!! lol!!! Also agree that your first and major concern is to sort out the earthing and bonding issues for this church. An in depth discussion with the local DNO on the two supplies coming into the church would be advantageous, one of them may well be obsolete. I would definitely try to make just one of them your main supply point with all distribution sub's etc, located in that supply heads location, not scattered around as it seems to be at the present. One more thing, i haven't seen many churches of this age and with steeples of a 100ft or so without some form of Lightning Protection, especially if the church stands in it's own open grounds.

Churches and there administration just about always plead poverty, just remind them they have a lawful responsibility to the public and there parishioners and staff to provide a safe environment within there premises at all times!!! If the denomination of this church is either C of E or Catholic, they can't be pleading poverty!! haha!!!

 

[colin durning]

Thanks Malcolm...great advice.

Iam going to have to go back round for yet other look. Looking back at the photo's myself i think your prob. right about that supply being redundant...but you never know!

I've been reluctant to get involved too much as you know what happens when just having a wee freebie look. Prob about 8hrs wee looks so far.
Initially, when i found the mettallic fitting had Volts on it, i had a quick look at the install and when found no earthing i lettered them stating the installation was dangerous. I then met with a couple of guys who deal with the financial side of the church, money for this is a big issue as the've only got dough for wind and water tight. I was asked to quote for earthing and if they manage to get some money, for rewiring some VIR circuits etc. Again, another wee look. This turned up another gas supply, water supply and the electrical supply that looks redundant and the PIR from 7 years ago.
Eng54, i hav'nt got a clue what kind of church it is. Its not RC. Lots of BB's and other groups use the hall but the church does not have many punters, there's another church of the same less than half a mile away with more punters so this one has been neglected a little.
Looking at it again its prob nearer 60-70ft, i had a look for lightning protection but did'nt see owt.
Hope to have more snaps soon

 

[colin durning]

Ok, i got access and took some more snaps with a borrowed camera, still uploading pics. Wish i'd used the BlkBerry now.

The redundant looking supply appears to be redundant.

The old part of the church is fed from an an old 60A sw directly of the meter http://i1088.photobucket.com/albums/i332/dubf8t/IMG_0874.jpg, this in turn feeds these two DB's. I'll call these DB3 and DB4http://i1088.photobucket.com/albums/i332/dubf8t/IMG_0869.jpg

This one may have the supply tattie jointed behind the fuse carriers as noted on PIRhttp://i1088.photobucket.com/albums/i332/dubf8t/IMG_0859.jpg

Here is what i'll call sub DB1 http://i1088.photobucket.com/albums/i332/dubf8t/IMG_0856.jpg
Sub DB2 http://i1088.photobucket.com/albums/i332/dubf8t/IMG_0872.jpg

What about the old PIR, fancy a swatch... i'm kind of getting into this now lol