Shower upgrade

[jif]

hi
I'm upgrading to a shower with 9.6kw power rating at 230v, my existing shower is fed by 6mm cable and when installed, a seperate consumer unit was used which contains only one fuse, the unit is fed from the meter and is marked as 45a on the unit but contains a 30A cartridge fuse.
I am going to change the cable to 10mm, do I need to and if so can I change the cartridge fuse/holder to 45A in the existing unit or would I be better changing this unit for an 45A MCB or RCD ?

 

[Big_Spark]

Glad to hear your uprating the cable to 10mm2.

Regarding it's protective device, you could upgrade the cartridge fuse and holder to 45A, however I always urge people to put showers on RCBO's, due to the inherent dangers of standing in water flowing from an electrically powered appliance should anything go wrong.

In case your unsure what an RCBO is, it is a device which incorporates the abilities of the MCB and the RCD in one neat package.

 

[securespark]

Suspect that Jif's shower supply is fed via a Wylex 104 (ivory box, red main switch?) which is from their "Dinosaur" range dating back to 1956...

So it will not know what an RCBO is, even if you stuffed one under its prehistoric nose!!

In which case, you will need to replace the 104 with something from this century.

No offence, FWL!

 

[galv]

if the shower is put on the rcd side of the cu would you still fit a rcbo?

 

[securespark]

What RCD side of what CU?

 

[Big_Spark]

Suspect that Jif's shower supply is fed via a Wylex 104 (ivory box, red main switch?) which is from their "Dinosaur" range dating back to 1956...

So it will not know what an RCBO is, even if you stuffed one under its prehistoric nose!!

In which case, you will need to replace the 104 with something from this century.

No offence, FWL!

No problems fella, I'm not a Dinosaur..YET!!

The cartridge fuse is better than the 3036, but when I suggested an RCBO, I was not meaning that it would fit in his board, I knew it would not if it hase Cartridge fuses in..should have made it clearer

 

[Big_Spark]

if the shower is put on the rcd side of the cu would you still fit a rcbo?

Galv, this is not a split load board, it has BS1361 Cartridge fuses in it and NO RCD just a Main Isolator.

To run this shower from an RCBO he will need to buy an enclosure and mount it beside the existing consumer unit and mount the RCBO in this.

 

[jif]

Thanks for the info folks - am I right in thinking I would need a 45A 230v 30ma rated RCBO and this would be in addition to my existing single fuse (albeit prehistoric) consumer unit and fitted between said unit and the shower, also if this is the case would the cable between the units have to be 10mm as the rest and how close would they have to be, don't think an extra unit would fit on the existing board, I'd have to fit another above it,
cheers
JIF

 

[Big_Spark]

Thanks for the info folks - am I right in thinking I would need a 45A 230v 30ma rated RCBO and this would be in addition to my existing single fuse (albeit prehistoric) consumer unit and fitted between said unit and the shower, also if this is the case would the cable between the units have to be 10mm as the rest and how close would they have to be, don't think an extra unit would fit on the existing board, I'd have to fit another above it,
cheers
JIF

There are two ways of doing this JIF. First way would be to connect an RCBO in it's own enclosure, to a fuse in your consumer unit using 10mm cable, then the output of the RCBO will go to your shower switch and so on.

Another way would be to buy a slightly larger enclosure, install into it a 63A Isolator and a 45A 30mA RCBO. The Input of the Isolator would then be piggy backed onto the supply from your meter, the output linked to the input of the RCBO, and the output of the RCBO to the shower switch.

Remember though, all links between enclosures should be in double insulated cable, not Twin and Earth. I know people do do it this way, but the cost of buying the correct cable is a few pounds for the amount you need.

 

[securespark]

J

Dinosaur referred to the Wylex 104, not you!! I can't talk, I was born in August 1966, a year after you, no? Ooops, cat-out-of-bag time....