Jump to content

DONT STAY LURKING AS A GUEST,

JOIN TEF AND BENEFIT FROM MEMBERSHIP:

CLICK HERE TO JOIN.
  •  
     
     
Countdown To Christmas!
 

 
  • 0

bondings


paul b b

Question

Hi all,

went to a job to day and there is no main bondings, there is a rod (tt system) cable is 6mm2, my question is, should the main bindings be 6mm or 10mm?

many thanks

Link to comment
Share on other sites
 

25 answers to this question

Recommended Posts

The Godfather

For TN-S or TT systems the csa of main protective bonding conductors must be a minimum of 6mm and not be less than half the csa of the main earthing conductor. 544.1.1

The Godfather

Link to comment
Share on other sites
 

thanks Godfarther!

i may as well use 4 for the sup bondings, unless you guys think otherwise (there is an rcd but onlu protects half the circuits)

This also made me laugh, When i was there the home owner (been there 9 months) phoned the guy he bought it from to ask where the main bonding was, he was sure it was there somewhere, the guy said on the phone that since he installd a rcd in 2006 that main and sup bondings we no longer required! ho ho ho. he showed me a PIR he recived with the house docs dated 2008 and 1 page long (i noted that there was nothing written in the main bondings box) shortest pir i have evere seen.

still more work for me!!

Link to comment
Share on other sites
 
Apache

ALL circuits need RCD on TT

Link to comment
Share on other sites
 

i told the guy that, but its a where do u stop job. there is about 12 way all taken up in a 2 bed house.

Link to comment
Share on other sites
 
Apache

If the wiring is to the 17th edition supplementary bonding may not be needed. Not in 2006 though.

If main bonds are put in place then my amateurish electrical brain says getting all circuits on an RCD is next in importance!

Link to comment
Share on other sites
 
The Godfather

The Don would consider RCD protection, essential to say the least on a TT system.

Don & His Boys

Link to comment
Share on other sites
 

I agree with you, but if the customer does not want it done.

Though i could change the main switch for a time delay s type, what cert would be needed for this?

also do you issue a cert for installing bondings?

Link to comment
Share on other sites
 
Apache
I agree with you, but if the customer does not want it done.

Though i could change the main switch for a time delay s type, what cert would be needed for this?

also do you issue a cert for installing bondings?

would be a MWC - no?

Link to comment
Share on other sites
 

is that to install a s type and bondings? both MWC?

Link to comment
Share on other sites
 
 
The Godfather
is that to install a s type and bondings? both MWC?

You could put both on 1 certificate.

Don

Link to comment
Share on other sites
 
Andy™
I agree with you, but if the customer does not want it done.

Though i could change the main switch for a time delay s type, what cert would be needed for this?

also do you issue a cert for installing bondings?

if he refuses to have an RCD, direct him to this

Link to comment
Share on other sites
 

paul ...your original question asked about the required size for the Main Bonding cables. The Godfather answered that for you...after that Im not sure what other work you intend to do, apart from maybe Supp bonding in the bathroom.If you do any other work then as long as its on the circuits controlled by the RCD you will only have to comment on your Certificate [E.I.C / MEWC. on the non rcd protected circuits cos you havent worked on them.If you work on the non rcd protected circuits then in most cases your wiring will have to be protected by an rcd due to either high Zs or Additional Protection requirements...Or both

Link to comment
Share on other sites
 

sorry to hijack but this is kinda related, u bond all incoming services correct, even oil. what if the oil tank is inside the house

Link to comment
Share on other sites
 
 
Apache
sorry to hijack but this is kinda related, u bond all incoming services correct, even oil. what if the oil tank is inside the house

I think the critical word is incoming. It's inside the house - can't bring in any potential so no need to bond. You'll be wanting me to bond me hot water cylinder next!

:D

Simple to the non-spark?

Link to comment
Share on other sites
 

thats waht i thought, the waters bonded but that comes in on plastic then copper.

and get this for an old argument. i rang eon and asked about exporting pme, they said its fine just dont touch the cut out fuse and ther stuff ect. i also talked to an eon engineer in the street he said he was a spark and they always exported pme to out buildings. i told him about loseing the nutral and he agreed but said loads of outbildings are wired this way and the rcd should trip

Link to comment
Share on other sites
 
Andy™
thats waht i thought, the waters bonded but that comes in on plastic then copper.

and get this for an old argument. i rang eon and asked about exporting pme, they said its fine just dont touch the cut out fuse and ther stuff ect. i also talked to an eon engineer in the street he said he was a spark and they always exported pme to out buildings. i told him about loseing the nutral and he agreed but said loads of outbildings are wired this way and the rcd should trip

plenty threads on here about exporting PME/making it TT etc

Link to comment
Share on other sites
 
Andy™
sorry to hijack but this is kinda related, u bond all incoming services correct, even oil. what if the oil tank is inside the house

only needs bonded if it can introduce a potential. just because its inside, doesnt mean its not extraneous. check continuity between the metallic parts and earth. if its under 23K ohms, bond it

Link to comment
Share on other sites
 
sorry to hijack but this is kinda related, u bond all incoming services correct, even oil. what if the oil tank is inside the house

oil tank inside the house? is that not againt building regs? and what sort of house is that?

Link to comment
Share on other sites
 
Andy™

maybe in an 'outhouse' as part of the house (access only from outside, but its still inside the main building)?

Link to comment
Share on other sites
 
NozSpark
oil tank inside the house? is that not againt building regs? and what sort of house is that?

I've seen oil tanks inside houses,,,

the last one was in a "mansion" type place,,, 158 rooms including cellar rooms.. the tanks (4 of them) were in the cellar.

BTW the electrics were shocking (no pun intended):o

Link to comment
Share on other sites
 

paul bb its a farm house mate, lots of strange goings on.

nozspark, the electrics are shocking here too.

its in the house access from inside, big metal tank.

thanks for the replies guys

Link to comment
Share on other sites
 

andy c. when u say bonding do u mean equipotential like the other services, or supplimentry like other extrenuous conductive parts.

the continuity is that with wander lead between pipe and and met.

it gets a bit much all this bonding, i mean the oil pipe enters the boiler were it will be earthed back through the plug, ringmain cpc back to the bord, so why the need for more, unless of course its main equpotential and in need of 10mm

Link to comment
Share on other sites
 
Andy™
andy c. when u say bonding do u mean equipotential like the other services, or supplimentry like other extrenuous conductive parts.

equipotential

Link to comment
Share on other sites
 

Archived

This topic is now archived and is closed to further replies.

×
  • Create New...

Important Information

Terms of UseWe have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.