bonding and tails size?

[raustin]

Just been to look at at a bedsit for a cu change. Straight forward enough, but only has 6mm main bonding conductor & water and the tails are 16mm.
Its a tncs with 60a fuse. So 2 questions
1 - Will the bonding need to be bought upto current regs and 16mm fitted for main conductor and 10mm for water.
2 - do the tails need to be upgraded?

Cheers Rich

 

[topquark]

What's the assessment of the loading for the bedsit? I'd suspect that the 16mm tails would be OK.

 

[raustin]

5 circuits in total.
Ring 32A
Cooker 32A
Immersion 16A
Storage heaters 16A
Lights 6A

 

[topquark]

Cooker with socket (extra 5A)?

 

[raustin]

Cooker with socket (extra 5A)?

Yeah, cooker with socket

 

[topquark]

Taking into account any diversity I make that:

Lighting 4A 2/3rds of total demand
RFC 32A (taken as 100%)
Cooker 15A (Based on the circuit, you should calculate this from the rating of the appliance as: 10A +30% of full load + 5A for the socket)
Heater 16A (no diversity allowed)
Immersion 16A (no diversity allowed)

 

[topquark]

I guess the assumption is here that this is a landlord meter?

 

[raustin]

ok thanks, how about the bonding? The landlord wants this done at the lowest price so can the bonding be worked out to show its adequate?

 

[topquark]

Application of the adiabatic equation should tell you. There's a sticky around with the calcs on for that.

Scrap that, just reread your post and you've said it's TNC-S so 10mm minimum I'm afraid.

 

[Des 56]

Scrap that, just reread your post and you've said it's TNC-S so 10mm minimum I'm afraid.

I am glad you posted again,I was convinced and sure it was an oversight on your part

 

[topquark]

I am glad you posted again,I was convinced and sure it was an oversight on your part

The beer has set in .... I'm stopping posting now!

 

[Des 56]

The beer has set in .... I'm stopping posting now!

i will have to speed up then,I am just starting my 2nd can of the Geordies finest ale

A late starter and night owl,I have to consume at least 2 more before I allow myself time off for some sleep

 

[raustin]

Scrap that, just reread your post and you've said it's TNC-S so 10mm minimum I'm afraid.

thanks guys as always really helpful.