by 333rocky333 »
Mon Dec 24, 2007 5:38 pm
To do it your way is not for the average diy person,if you are asking how to do it ,i would not advise you to even attempt it.
Them one way units are more for older properties with existing service blocks already fitted and seperate switchfuses for each circuit each branching off the service block, with the arrival of consumer units that method is hardly used now.
Personally I think its bodging and I would not know any elect, for the sake of replacing a 3 way Rewirable board, that would even consider doing it that way.
Get a nice 6 way board for about 60 pound plus fitting will look really neat and no more hassle with fuse wire ,
It is notifiable work and also a criminal offence as you will be breaking the electric board seal to isolate the supply, there is also the potential of electrocuting yourself or fusing the entire street.
It may sound harsh but the danger there is very serious
The wires would go from the meter to the service block, then from the service block to the existing fusebox, and also from the service block to the new shower consumer unit ,it is good practice to fit a rcd in that .
Both units need to be suitably earthed also.
The tails need to be suitable and double insulated,and the earth bonding needs to be confirmed before even starting .
If you have 100amp supply then these tails are going to likely be 25mm
you will struggle to get them in your unit, and have even more problems getting them in your old 3 way board.
You can possibly downrate the size of these cables but would not advise without not knowing what you have.
Even though you have the bits I would still look at replacing the board now,your old board will proberly not conform with new regs out january,so any future work you require may need the board changing anyway.
If presently you have 3 rewirables only it is likely your existing tails as well as your bonding was installed some time ago and is now to small for the current regs.
This has to be sorted prior to any work done,and is essential for your own safety.
If not it will not pass any inspection.
Sorry