Highway_Star
Member
- Messages
- 299
Afternoon all.
I'm about to embark on sorting the power supply to my garage (currently a length of 2.5mm T&E buried without any protection), and spurred off the downstairs ring main.
To that end I've procured a length of 16mm SWA & Glands which will be clipped to joists under the house. Where it goes outside it will be under decking which joins the house to garage and will be clipped to the decking joists, then enters the garage.
This is part of a bigger electrical project here. A lot of the lighting circuits aren't earthed and the DB whilst being all Siemens MCBs has no RCD protection, nor is it available for that board.
So I was thinking this:
Replace the DB with a Hager, dual RCD effort. Having rewired where necessary and made all the internal stuff good. Upstairs sockets are actually two radials, one is spurred off the downstairs ring, the other is rather bizzarely spurred of the kitchen ring. Eh?!
That will be made good into three rings, kitchen, downstairs and upstairs. It's a great house to work on, there is cellar below the ground floor, loft above the upstairs ceiling and all the downstairs lighting cables come from the eaves, and are run in steel conduit, so other than a but of pulling it's not too bad. I can't see me having to lift any floor boards or chase walls. There's a foot square pipe box in one corner and the same in another corner for cables to upstairs.
Then fit an 80A 100mA RCD to supply the garage. Either in the new DB, or more likely as a stand alone isolator. I can do this easily enough because there is a 100A breaker between the meter and the DB, said 100A breaker has spare terminals.
So the 80A 100mA RCD is protecting the cable adequately.
I'd then install a new DB in the garage with probably a 63A 30mA RCD incomer, and a few MCBs of the appropriate ratings. I'll need a 3x6A circuit for lights (internal + external) & alarm system, 32A ring main and a couple of 16A for the welder/plasma. Lathe is a Myford ML10 so will happily go on the ring. Pillar drill, grinder, compressor etc aren't big and and will happily go on the ring. Very intermittent use anyway.
Does this make sense to the panel? Or am I over complicating it? I've a strong desire to do it once, properly.
I'm about to embark on sorting the power supply to my garage (currently a length of 2.5mm T&E buried without any protection), and spurred off the downstairs ring main.
To that end I've procured a length of 16mm SWA & Glands which will be clipped to joists under the house. Where it goes outside it will be under decking which joins the house to garage and will be clipped to the decking joists, then enters the garage.
This is part of a bigger electrical project here. A lot of the lighting circuits aren't earthed and the DB whilst being all Siemens MCBs has no RCD protection, nor is it available for that board.
So I was thinking this:
Replace the DB with a Hager, dual RCD effort. Having rewired where necessary and made all the internal stuff good. Upstairs sockets are actually two radials, one is spurred off the downstairs ring, the other is rather bizzarely spurred of the kitchen ring. Eh?!
That will be made good into three rings, kitchen, downstairs and upstairs. It's a great house to work on, there is cellar below the ground floor, loft above the upstairs ceiling and all the downstairs lighting cables come from the eaves, and are run in steel conduit, so other than a but of pulling it's not too bad. I can't see me having to lift any floor boards or chase walls. There's a foot square pipe box in one corner and the same in another corner for cables to upstairs.
Then fit an 80A 100mA RCD to supply the garage. Either in the new DB, or more likely as a stand alone isolator. I can do this easily enough because there is a 100A breaker between the meter and the DB, said 100A breaker has spare terminals.
So the 80A 100mA RCD is protecting the cable adequately.
I'd then install a new DB in the garage with probably a 63A 30mA RCD incomer, and a few MCBs of the appropriate ratings. I'll need a 3x6A circuit for lights (internal + external) & alarm system, 32A ring main and a couple of 16A for the welder/plasma. Lathe is a Myford ML10 so will happily go on the ring. Pillar drill, grinder, compressor etc aren't big and and will happily go on the ring. Very intermittent use anyway.
Does this make sense to the panel? Or am I over complicating it? I've a strong desire to do it once, properly.
if your running a 16mm cable out to the garage the best bet is fit a 60 amp switchfuse at meter source providing the electricity board are supplying the earth then out to garage and fit an rcd protected db with 30milliamp trip mainswitch or rcbo breakers depending on how much u want to spend if. the supply to house is overhead tt supply and no earth u would need a switchfuse fitted with a preferable 100milliamp slow trip rcd main switch
never had a problem yet 
