the doctor
Part P Doctor ™
- Joined
- Mar 1, 2008
- Messages
- 580
- Reaction score
- 1
Hello All,
A couple of weeks back I was doing a mains change on a local furniture shop. The mains was being converted from single to three phases to take full advantage of his large south facing roof for solar panels. Anyway the existing set up was a single phase TT with NO RCD and NO VISIBLE ELECTRODE. In Northern Ireland, lots of jobs are like this by the way
I fitted a new board and left tails to be connected it to the new meter when the man arrived. While I was at it the other week I drilled the floor of the mains room and hammered in a brand new rod. I took a reading and got 350 ohms. This as we know is a little high but I fitted a time delay main 100mA RCD and BS 7671 allows 500 ohms for that bad boy.
I was there on Thursday morning to complete the change over on the job and to be present when the meter man landed. I could see that he was a bit perturbed by all the wiring hanging round but said he would go ahead after my explanation of my plan. His sheet confirmed the install was a TT and walked out saying he was getting his tester to check the rod resistance. The DNO limit was 200 Ohms he said and asked had I checked it. I replied I had and admitted it was on the high side. When he walked out, in my blind panic I got my bottle of lemonade sat on the side and poured it down round the rod. I then swept the drill dust I hadn't cleaned up previously around the deed to soak up the crime and waited.
He came back in and started his testing. I was waiting for bad news when there was a bleep and a sharp intake of breath. " You're a lucky man" he says, " The rod measures 195 Ohms"
If only he knew :innocent
A couple of weeks back I was doing a mains change on a local furniture shop. The mains was being converted from single to three phases to take full advantage of his large south facing roof for solar panels. Anyway the existing set up was a single phase TT with NO RCD and NO VISIBLE ELECTRODE. In Northern Ireland, lots of jobs are like this by the way
I fitted a new board and left tails to be connected it to the new meter when the man arrived. While I was at it the other week I drilled the floor of the mains room and hammered in a brand new rod. I took a reading and got 350 ohms. This as we know is a little high but I fitted a time delay main 100mA RCD and BS 7671 allows 500 ohms for that bad boy.
I was there on Thursday morning to complete the change over on the job and to be present when the meter man landed. I could see that he was a bit perturbed by all the wiring hanging round but said he would go ahead after my explanation of my plan. His sheet confirmed the install was a TT and walked out saying he was getting his tester to check the rod resistance. The DNO limit was 200 Ohms he said and asked had I checked it. I replied I had and admitted it was on the high side. When he walked out, in my blind panic I got my bottle of lemonade sat on the side and poured it down round the rod. I then swept the drill dust I hadn't cleaned up previously around the deed to soak up the crime and waited.
He came back in and started his testing. I was waiting for bad news when there was a bleep and a sharp intake of breath. " You're a lucky man" he says, " The rod measures 195 Ohms"
If only he knew :innocent
