Chippie
Member
- Messages
- 855
- Location
- Newcastle upon Tyne, UK
My garage is currently supplied by a buried swa cable fed from the cu in the house and backed by a 16A mcb. It is a split board with earth leakage on each half.
I want to upgrade to a minimum supply of 30A as my large compressor trips the breaker(16 A type B feeding a radial circuit with 2.5mm conductors) in the garage cu.
The current cu has a dp isolator/30mA rcd rated at 63A.
Loads:
The radial circuit is to be be uprated to ring and backed by a 20A mcb. There are essentially 3 fixed loads on this…a lathe with a 1.5kw motor, a milling machine with the same size motor and a small freezer. 20A is considered ample as there’s minimal likelihood of running both lathe and mill simultaneously. Both machines are fed via a vfd, so I ignore PF.
There are 6 4’ fluey lights fitted with led tubes, fed from a 6A mcb.
An outside pir led flood fed from a 6A mcb.
An external socket feeding the caravan supply with a 10A mcb
A rough n ready calc on load current puts me at about 30A, with everything running…
The cable run is around 10m, with a 230v supply figure and my load current gives me a cable of 4.0mm.
So I want to run a swa supply from the meter box, split the house tails from the isolator into blocks and feed the garage via a switch fused isolator….
Any one see any problems with this?
I want to upgrade to a minimum supply of 30A as my large compressor trips the breaker(16 A type B feeding a radial circuit with 2.5mm conductors) in the garage cu.
The current cu has a dp isolator/30mA rcd rated at 63A.
Loads:
The radial circuit is to be be uprated to ring and backed by a 20A mcb. There are essentially 3 fixed loads on this…a lathe with a 1.5kw motor, a milling machine with the same size motor and a small freezer. 20A is considered ample as there’s minimal likelihood of running both lathe and mill simultaneously. Both machines are fed via a vfd, so I ignore PF.
There are 6 4’ fluey lights fitted with led tubes, fed from a 6A mcb.
An outside pir led flood fed from a 6A mcb.
An external socket feeding the caravan supply with a 10A mcb
A rough n ready calc on load current puts me at about 30A, with everything running…
The cable run is around 10m, with a 230v supply figure and my load current gives me a cable of 4.0mm.
So I want to run a swa supply from the meter box, split the house tails from the isolator into blocks and feed the garage via a switch fused isolator….
Any one see any problems with this?
