8.5kw shower 6mm2 cable on 32amp mcb ????

[ianphilip007]

hi there

after some advice re the above problem when just doing a simple like for like shower replacement, as it keeps cropping up. 8.5kw showers, 6mm2 cable protected via a 32amp MCB. now i would usally protect a 8.5kw shower with a 40a mcb on a 6mm cable (ref mthod c) . now i know a 8.5kw shower ( 8500/240 = 35.4 A) will never really ever threaten to trip a 32Amcb. So what do you do replace the 32 with a 40 ? or just leave the 32 in place and note on the cert ?. My concern is that i dont know why it was fused at 32A in the first place, it could be re ref method or it could have been just installed wrong.

 

[malcolmsanford]

To be honest Ian unless the cable is reference method C you can't really replace the PD to 40amp

Personally I would give the customer the choice upgrade the cable to 10mm-40/45amp or leave the 32amp in with the 6mm.

On the side I would be telling them exactly what you posted, the 32amp will be fine, and if after 15 years it starts to wear out you will price them up the upgrade

 

[telectrix]

just what i was going to say. try clamping the current. bet it's under 35A at worst case.

 

[ianphilip007]

that was my thinking malcom, safer to leave on the 32 if ref method is not known, would you note it on the cert (re unknown ref method)

 

[malcolmsanford]

What cert for a like for like replacement?

If you want to issue them a MEIWC fine, and if you want to note it in Part 2 fine again, but personally I would not note it, just give them the verbal option

 

[ianphilip007]

i always cert when replacing a shower as i like to carry out a full circuit test. i know not strictly nessacary as its like for like. i think ill note the existing 32a mcb in comments section re existing installation and explain to customer.

 

[malcolmsanford]

i always cert when replacing a shower as i like to carry out a full circuit test. i know not strictly nessacary as its like for like. i think ill note the existing 32a mcb in comments section re existing installation and explain to customer.

Admirable and fine bottom covering excercise

 

[ianphilip007]

lol spot on malcom