hi, ive previously posted regarding new consumer unit to house, but my new question is-

I have a old style fusebox and when i had a electric shower installed, i had a separate mini consumer unit installed similar to one you would have in a garage, with the new style rcd trips.

I plan on having a supply taken from the house approx 10m, using 4mm swa armoured cable and two double sockets and two 28watt light fixtures in the shed with a mini consumer unit fitted in the shed.

this work will be completed by an electrician, but looking at cost, is it possible to use a similar setup to the shower, to make the connections inside, or how this could be done, if i didnt want to upgrade my consumer unit, trying to cut costs with having a new consumer unit fitted, to safeguard the entire property supply.

many thanks

liam

Much depends on how much power you need. Using 4mm cable will allow for upgrade latter if you need more power but to keep costs low then you need to aim below 13A. With a 13A supply one can use a RCD FCU in the house and in the shed use a switched FCU as the light switch with a 3A fuse. Then no need for any consumer units.

If your not using an electrician do remember there may be earthing problems if a long distance.

There are two types of RCD FCU's those with passive and those with active RCD's. If close to consumer unit then a passive can be used. These do not auto trip with power cut. But away from consumer unit then an active should be used. This ensures should under fault conditions the voltage drop it will fail safe.

A little confusing Liam, you did not finish the other thread by repling to Billy Goat.
The best step forward is a house consumer unit, then everything is protected, shed and shower plus whole house becomes very safe and easy to manage!
I had my kitchen upgraded, circa 1980's house, we went from a fuse box to double RCD (split) CU and the electrician did it in minimal cost-time and I can vouch it is money well spent (nice certificate as well).
If you are concerned that the shed supply is high risk of tripping and knocking out the house supply, then make use of the redundant shower CU but wired for the shed and fed seperate to the house circuit RCD's.