Oh no, not another 'how do I wire up my garden shed' question...
Well, hopefully this one should be a bit more thought provoking.
I recently purchased a small farm yard and I will need to rewire it. As this is a commercial installation I don't have to worry about part P. I'm an electronics designer by trade and I do a fair amount of repair work on large 3-phase industrial machines so i'm pretty familiar with working on mains voltage wiring. However I'm not so clear on the wiring regs.
So here's the setup. I have a 50m long concrete+wood barn (was a chicken barn but will now be a workshop). At one end is a 100A single phase supply that I think is TNC-S, fed from a transformer 20m away. I'm basing that assumption on the earth terminals built into the meter and the fact that there is no earth rod. At the other end of the barn is a 20m steel framed covered yard then a smaller wooden barn that I'm converting to an electronics workshop.
Currently only the main barn has any wiring and it's pretty dodgy so I will scrap it and start again from scratch. My current plan is as follows:
From the meter I'll install a 100A fused isolator. The meter needs to be relocated so I'll get it connected when they do that. After the isolator I'll have a CU to feed various supplies at that end of the barn (lights + a couple of sockets). The isolator will also feed a 30m long 25mm or 35mm cable to the middle of the barn where I'll have another CU to feed various machines, welders etc. From there I'll run 50m of 10mm to the office. I won't need more than 20A at the office (computers, test gear, lights + night storage heater). Does that sound like a workable plan?
Is it acceptable to have both a 32A round socket and 13A sockets on the same 4mm spur, as long as it is all on 32A MCB? I can't see any reason why this should be a problem.
I have a 30m length of new 35mm twin (not armoured) cable that I've had lying around for a few years. Could I use this with a separate earth cable? It would be nice to use this cable as I have it but it's not a major issue to buy some SWA if need be.
The bit i'm not so sure about is earthing. Do I change to TT? I'm also not sure about what size my earths need to be. I assume I need to bond the steel building. Would I need to bond each upright or just one as they are all connected through the steel framework? Any advice would be greatly appreciated.
Well, hopefully this one should be a bit more thought provoking.
I recently purchased a small farm yard and I will need to rewire it. As this is a commercial installation I don't have to worry about part P. I'm an electronics designer by trade and I do a fair amount of repair work on large 3-phase industrial machines so i'm pretty familiar with working on mains voltage wiring. However I'm not so clear on the wiring regs.
So here's the setup. I have a 50m long concrete+wood barn (was a chicken barn but will now be a workshop). At one end is a 100A single phase supply that I think is TNC-S, fed from a transformer 20m away. I'm basing that assumption on the earth terminals built into the meter and the fact that there is no earth rod. At the other end of the barn is a 20m steel framed covered yard then a smaller wooden barn that I'm converting to an electronics workshop.
Currently only the main barn has any wiring and it's pretty dodgy so I will scrap it and start again from scratch. My current plan is as follows:
From the meter I'll install a 100A fused isolator. The meter needs to be relocated so I'll get it connected when they do that. After the isolator I'll have a CU to feed various supplies at that end of the barn (lights + a couple of sockets). The isolator will also feed a 30m long 25mm or 35mm cable to the middle of the barn where I'll have another CU to feed various machines, welders etc. From there I'll run 50m of 10mm to the office. I won't need more than 20A at the office (computers, test gear, lights + night storage heater). Does that sound like a workable plan?
Is it acceptable to have both a 32A round socket and 13A sockets on the same 4mm spur, as long as it is all on 32A MCB? I can't see any reason why this should be a problem.
I have a 30m length of new 35mm twin (not armoured) cable that I've had lying around for a few years. Could I use this with a separate earth cable? It would be nice to use this cable as I have it but it's not a major issue to buy some SWA if need be.
The bit i'm not so sure about is earthing. Do I change to TT? I'm also not sure about what size my earths need to be. I assume I need to bond the steel building. Would I need to bond each upright or just one as they are all connected through the steel framework? Any advice would be greatly appreciated.