We went to a to a big contractors site today to look at some pat testing for a sub contractor. We had a heated disscusion on way back about what we had seen.
While i was there i noticed 5 10kva single phase transformers dotted about the scaffold.
The transformers were all fed in 6mm swa cable tied to scaffold
These transformers were supplied with type c 32a rcbos. Fed from a 240v metal board inside a metal enclosure. This was housed inside a wooden purpose built hut. this was approx 8 lifts up about 20M.
The supply to this sub was a run of 16mm armour straight into site office fed from a 63amp single pole CB where there was a temp tp&n board. Tp&n board was fed by a 50mm swa that dissapeared into a hole in concrete floor where i asssume the incomer was.
Now i have no idea what supply it was but im hoping its not a PME.
I argued the 240v sub main have been rcd protected for additional protection? my mate said not because if transformers are supplying lighting on the scaffold then if it trips then blokes have no light. So we debated if the scaffold should have been bonded where the sub main on scaffold was - i said no because scaffold is not an exposed conductive part.
anyone have any opinion?
While i was there i noticed 5 10kva single phase transformers dotted about the scaffold.
The transformers were all fed in 6mm swa cable tied to scaffold
These transformers were supplied with type c 32a rcbos. Fed from a 240v metal board inside a metal enclosure. This was housed inside a wooden purpose built hut. this was approx 8 lifts up about 20M.
The supply to this sub was a run of 16mm armour straight into site office fed from a 63amp single pole CB where there was a temp tp&n board. Tp&n board was fed by a 50mm swa that dissapeared into a hole in concrete floor where i asssume the incomer was.
Now i have no idea what supply it was but im hoping its not a PME.
I argued the 240v sub main have been rcd protected for additional protection? my mate said not because if transformers are supplying lighting on the scaffold then if it trips then blokes have no light. So we debated if the scaffold should have been bonded where the sub main on scaffold was - i said no because scaffold is not an exposed conductive part.
anyone have any opinion?