TT system inspection pit

[robd]

Afternoon all, Can anyone tell me if there's a reg stating you need to use inspection pit/box/cover or whatever you want to call it for the main earth rod/rods or is it just good practice.

Thanks

 

[Pat Tester]

I don't know of any specific reg however the clamp must be protected from damage both physical and from corrosion etc and remain accessible for future testing etc,
I used to use the silly little round boxes, designed by an utter ****, what utter utter ****s they were; However after one gruelling incident when I snapped the crimp eye for the second time, to stop me going on the rampage it was necessary repeatedly bang my head against a wall until i lost consciousness.
Therfore I now prefer to use the pits that are available from screwfix. There is so much room inside, you can stash a balaclava, neoprene gloves and a fair length of rope along with a selection of knives and further more you don't waist 200mm of rod above ground. A right blessing I say.

 

[robd]

ha ha yes I too would like to get my hands on whoever thought they were a good idea. Cheers

 

[MNR]

Is there anything stopping you using a galv adaptable metal box labeled up?

 

[Engineer54]

Is there anything stopping you using a galv adaptable metal box labeled up?

Yes!! ...Corrosion sort of springs to mind!! lol!!

 

[Engineer54]

I don't know of any specific reg however the clamp must be protected from damage both physical and from corrosion etc and remain accessible for future testing etc,
I used to use the silly little round boxes, designed by an utter ****, what utter utter ****s they were; However after one gruelling incident when I snapped the crimp eye for the second time, to stop me going on the rampage it was necessary repeatedly bang my head against a wall until i lost consciousness.
Therfore I now prefer to use the pits that are available from screwfix. There is so much room inside, you can stash a balaclava, neoprene gloves and a fair length of rope along with a selection of knives and further more you don't waist 200mm of rod above ground. A right blessing I say.

You should always always use earth pit boxes that are flush to the ground. They are robust, they will protect the earth rod connection, convienient for future testing, and last but not least, is a visible location marker.

These black plastic box arrangements that basically sit on top of the rod, are 5 minute wonders, they protrude above ground level so are always prone to mechanical damage, and are just not built to sustain any physical abuse be it accidental or otherwise!!

There are other methods that will not require any form of earth pit or box, but not really suitable for domestic, or single rod position installations...

 

[ackbarthestar]

You could dig a proper service pit and bury your 1.2m rod in a couple of extra feet...... that should keep some of the posters on here happy :rolleyes4::lol::lol:

 

[IQ Electrical]

542.3.2 suitably protected against corrosion....

 

[MNR]

Yes!! ...Corrosion sort of springs to mind!! lol!!

They were not dug into ground but fixed to the concrete, steel conduit dropped down to box . The do as you likeys had been down a whole road and taken every cable from there rods. We did suggest pits but the housing association point blank refused the installation of the pits.

 

[Engineer54]

They were not dug into ground but fixed to the concrete, steel conduit dropped down to box . The do as you likeys had been down a whole road and taken every cable from there rods. We did suggest pits but the housing association point blank refused the installation of the pits.

Sorry MNR, i can't picture your above description, fixed to what concrete, and steel conduit to what box???

I'd like to hear what objection this housing association would have to the universal ''Standard'' method of protecting earth electrode positions. They would have to have a cast iron reason, for refusing, ....and i can't think of any!! lol!!!

 

[MNR]

Hole through high level out of external wall, into terminal box down wall to ground level, right angle bend on conduit connected to adaptable box with brass bush and coupular.

There objection was they did not want the disruption of gunning up concrete the rods go through to install the pits, this translates to this way was cheaper for them.

 

[Engineer54]

Hole through high level out of external wall, into terminal box down wall to ground level, right angle bend on conduit connected to adaptable box with brass bush and coupular.

There objection was they did not want the disruption of gunning up concrete the rods go through to install the pits, this translates to this way was cheaper for them.

Sorry MNR, still a little confused with the picture!! lol!! Where is the rod connection in all this ?? Are you saying that they have broken thru concrete to drive the rod in, then installed an adaptable box over the top of it where the connection to rod is located?? How far from the building outer wall has these rods been located?? Please don't tell me virtually right next to the wall will you?? lol!!!

What i can't quite follow, I take it that this housing association estate is an all TT system, set-up, which frankly i've never seen on this scale before in the UK. ...Anyway whatever, A real silly question now, ....Why did they cast the concrete before the rods were in position, with the ground pit chambers in place?? It's not as if they didn't know that all these houses needed an earth rod, and those rod positions would have been clearly shown on the ground works services layout drawings. This sounds like a real buck-shee set-up, i wonder how long they expect those thin Galv adaptable boxes to last anyway. ..lol!!!

 

[Engineer54]

Oooops. didn't read one of your posts too well, ....this arrangement is to replace a previous installation that had been vandalised by the cable snatchers... haha!! Scrub the silly question in this instance then...lol!!

 

[MNR]

Yep, not a new installation. Before they where just clipped down wall to rod with no protection over any of it.