agricultural question

[telectrix]

not had much experience of agri. work so am a bit at a loss. farmer wants a double socket fitting on a cattle ( for want of a better word) run. it's a steel enclosure, gated, in which the cattle pass through single file. the structure is bolted to the concrete floor, obviously, an IP rated socket, fed from above with flexible conduit. supply will be from an RCD protected dis. board. i'm unsure of what bonding i need to carry out. section 706 ( restricted movement) also applies. considering the general state of the existing installation, i will have to carry out tests on the earthing ( think it's TN-S) and obviously fullt test the RCD. also, i can't see any evidence of the structural steel being bonded.any input welcome. thanks in advance guys.

 

[pushrod]

Have some recollections of if it is a reinforced concrete floor the steel in it must be bonded and that must have mechanical and corrosion protection as well- would think that is a total pain if not already done. Also remember that ordinary metal conduit not considered acceptable due to corrosion but surprisingly, to me at least, that plastic was. Surprised me, if i am remembering correctly, as you also have to be careful about rodents and it never strikes me as being particularly strong either, particularly if a cow decides it wants to chew it! Although i think all electrical equipment is supposed to be inaccessible to livestock.

 

[Chr!s]

i'm unsure of what bonding i need to carry out

Supplementary, between all extraneous and exposed

section 706 ( restricted movement) also applies

I wouldnt say so, 3rd paragraph

i can't see any evidence of the structural steel being bonded.any input welcome. thanks in advance guys.

is it extraneous if so all extraneous parts require bonding, test to see if it is effectively connected to met, if not requires main bonding

considering the general state of the existing installation, i will have to carry out tests on the earthing ( think it's TN-S) and obviously fullt test the RCD

Yes youll need to know earthing arrangement, Expect front end rcd, 100ma td or max 300ma
ssockets <32 30ma, sockets >32 100ma

 

[telectrix]

impossible to check if concrete floor has steel reinforcement. if it has it's buried under the concrete.

 

[Engineer54]

As Chris posted, structural steel work will need to be bonded back to the MET as will any incoming services to the building. I doubt if the slab steelwork has been bonded. If there was a substantial tied together steel cage work type reinforcing, it will be acting as a biggish ground field and should have been bonded to the steel structure and back to the MET.

The one thing you do need to be aware of is, that the touch voltage requirement where livestock is a factor, is reduced to 25 volts...

 

[Chr!s]

impossible to check if concrete floor has steel reinforcement. if it has it's buried under the concrete.

Not to much of an issue providing its not pme

 

[telectrix]

going later today to check Zdb and other parameters, make sure existing earthing etc. is adequate. problem at the moment is it's that cold , can't grip tools.