Hi, I'm looking for a bit of advice on a volt drop query we have in our office.
I'll explain the scenario and I would really appreciate any opinion's and advice.
We were asked to wire a 3ph 100A supply into a barn, that would later be used to feed a new build house. The meter and supply comes into a GRP at the site boundary. We installed 125m of 50mm 5 core SWA from here into a distribution board in the barn. The volt drop was coming back at approx 2.4%. At the time of installation the details of the new build house were unknown.
Now a third part electrician has come into look at the site and the proposed new house. They are saying that the supply is too small based on VD and he is suggesting it should have been a 95mm!
95mm seems overkill to me. They are claiming that 2.4% plus the supply to the house, plus the final circuits is going to add up to more than the 3% allowed for lighting, but it still doesn't sit right with me.
My question really comes down to.. Can we use diversity in relation to VD when sizing cables like this? I feel like there needs to be some common sense brought into the equitation, but unsure how I can put this across to the client and refer it back to the regs.
Many thanks in advance.
I'll explain the scenario and I would really appreciate any opinion's and advice.
We were asked to wire a 3ph 100A supply into a barn, that would later be used to feed a new build house. The meter and supply comes into a GRP at the site boundary. We installed 125m of 50mm 5 core SWA from here into a distribution board in the barn. The volt drop was coming back at approx 2.4%. At the time of installation the details of the new build house were unknown.
Now a third part electrician has come into look at the site and the proposed new house. They are saying that the supply is too small based on VD and he is suggesting it should have been a 95mm!
95mm seems overkill to me. They are claiming that 2.4% plus the supply to the house, plus the final circuits is going to add up to more than the 3% allowed for lighting, but it still doesn't sit right with me.
My question really comes down to.. Can we use diversity in relation to VD when sizing cables like this? I feel like there needs to be some common sense brought into the equitation, but unsure how I can put this across to the client and refer it back to the regs.
Many thanks in advance.
