I have trawled through numerous prior advices on this subject but can't quite find matching variables so please excuse me for taking you over old ground again. The bulk of the work will be done by a Canadian relative at the end of this month. (He built the garage last year). He is very competent but I am concerned by the differences in specification and practice. I will certainly be more confident if his proposals compare favorably with any advice that you are able to give me.
I need to power up my new garage (30M2) which incorporates a study+WC & basin+a sink in the garage area. I also intend to replace the house CU but I will use a local spark once the garage job is done. At the moment I have an overcrowded fusebox.
The maximum load iwould derive from:
LIGHTS Internal lighting say 400W...External lighting say 500W
STUDY 3Kw heater/computer/printer/scanner/copier
CLOAKROOM Instantaneous water heater 5.5Kw
GARAGE A second instaneous water heater5.5Kw/several 13a outlets for domestic power tools inc.,extension to lawnmower etc. and a small chest freezer at 5oow.
TOTAL: 20KW RATIONALISED TO c.10KW
The builder has already buried 5m of 3 core SWA from a point in the house's floor void which is 6m from the main CU.. I do not know what size the cable is. It looks substantial and imeasures 15mm dia??
QUERIES
1) Should the freezer to be excluded from RCD?
2) Should the sockets be on a ring or radial and/or separate for study and garage?
3) What to do with the two 5.5KW water heaters. By their nature they will be used minimaly and for a matter of seconds. They will both be within 2.5m of the location of the CU?
4) Can you guys tell from the 15mm., dia., of the SWA whether it is sufficient or should I chop a piece off to ID the rating accurately (got a feeling I know the answer)?
5) I was thinking of using a galvanised junction box at each end of the SWA with glands. At the garage end the box would be adjacent to the CU...What size cable should I use between the two?
6) On the house side would 10mm T&E be sufficient over the 6m run?
7) Given that the armour will be connected to earth should the core wire also be used? Isn't there an issue in running two earths in close parallel?
8) What size RCD ?
I hope that I am not stretching your patience with this lot.
Many Thanks in advance
Tony
I am in Scotland (Differs from part P)
Ihe property is PME
I need to power up my new garage (30M2) which incorporates a study+WC & basin+a sink in the garage area. I also intend to replace the house CU but I will use a local spark once the garage job is done. At the moment I have an overcrowded fusebox.
The maximum load iwould derive from:
LIGHTS Internal lighting say 400W...External lighting say 500W
STUDY 3Kw heater/computer/printer/scanner/copier
CLOAKROOM Instantaneous water heater 5.5Kw
GARAGE A second instaneous water heater5.5Kw/several 13a outlets for domestic power tools inc.,extension to lawnmower etc. and a small chest freezer at 5oow.
TOTAL: 20KW RATIONALISED TO c.10KW
The builder has already buried 5m of 3 core SWA from a point in the house's floor void which is 6m from the main CU.. I do not know what size the cable is. It looks substantial and imeasures 15mm dia??
QUERIES
1) Should the freezer to be excluded from RCD?
2) Should the sockets be on a ring or radial and/or separate for study and garage?
3) What to do with the two 5.5KW water heaters. By their nature they will be used minimaly and for a matter of seconds. They will both be within 2.5m of the location of the CU?
4) Can you guys tell from the 15mm., dia., of the SWA whether it is sufficient or should I chop a piece off to ID the rating accurately (got a feeling I know the answer)?
5) I was thinking of using a galvanised junction box at each end of the SWA with glands. At the garage end the box would be adjacent to the CU...What size cable should I use between the two?
6) On the house side would 10mm T&E be sufficient over the 6m run?
7) Given that the armour will be connected to earth should the core wire also be used? Isn't there an issue in running two earths in close parallel?
8) What size RCD ?
I hope that I am not stretching your patience with this lot.
Many Thanks in advance
Tony
I am in Scotland (Differs from part P)
Ihe property is PME