Garage can I do this

[oldtimer]

Hi guys
Did some work in a house where there is a 12 way DB TNS and a 30A switched fuse for a garage / workshop (2 levels) about 30 metres from the house.Both DB and 30A SW/fuse are connected to live blocks from the meter.

The garage is supplied via a 6mm LNE run in galvy conduit supplying a 4 way wylex board and the Zs is 0.66 an PFC is 0.54 L-N and 0.35 L-E .

The customer wants a quote to upgrade the DB so here is my thoughts and would appreciate any feedback.

Install a 15 twin RCD board each RCD has 6 breakers so thats the house covered and the DB has 3 unprotected ways. My thought was to change the DB and in the future fit a 32A RCBO into the non protected side of the board for the garage supply replacing the 30A SW/fuse with a 45A switch and replaceing the old 4 way rewireable fuse board in the garage with a 4 way circuit breaker board.
The board has 2 x 5A and 2 x 16A fuses ie power and light for each level.

Also to point out the build looks like a 2 double garages one on top of the other.

Socan I do this and what is the definition of this Garage/workshop

Many thanks

Just to ad the DB Zs is 0.15 , PF 2.4 L-N , 1.5 L-E

 

[ezzzekiel]

sounds fine to me providing calcs are all in order and vd is ok, although i would fit a small cu with rcd in the workshop to save walking to house if rcd trips, the supply cable is mechanically protected.

 

[oldtimer]

Thanks for the reply the reason why I thought about fitting the RCBO at the CU in the house was that it covers the supply cable throughout the house in in the conduit running along the garden wall.

As for VD I measured 235 at the board and 233 at the garage.

The reason I was looking for clarification was I have never had this situation before plus I remember reading here about detached garages and earthing

 

[sparkylad]

Hi oldtimer. if .as seems likely , there is extraneous conductive parts in the Garage / workshop then you will have to either
1. Run in a 10mm Main Bonding conductor from the Met to these E.C Parts...or
2. Convert the exterior supply to TT. inc a rod installation.