Friday morning stupidity,nearly didn't make lunch time!

[Deleted member 9648]

Carrying out a few minor remedials following an EICR on a small rented cottage this morning. One item was to replace the immersion heater stat for one with a thermal cut out. Switched off DP isolator alongside the tank, check with probes, crack on. Only trouble was the airing cupboard was a bit of a squeeze, and in manoeuvring around to get better access I managed to knock the switch back on with my elbow while having the live conductor in my other hand. Wrist in contact with the copper hot pipe on the top of the tank I got one hell of a poke, didn't half 'effin hurt. Had to have a bit of a sit down and contemplate, was working alone in an empty cottage, could have been the last EICR I ever done.
That's how it happens boys and girls, safe isolation every time with a moments thought for the unexpected before diving in. Lesson learnt....well 'till the next time anyway.
On another note, was a TT system with an Ra of 260 ohms, earth rod was in good condition with a 16.0mm main earth lead properly lugged to the rod.
I didn't code it because....
It complies with Bs 7671, which does not give a max value of Ra, the 200 ohms mentioned is only mentioned as possibly being unstable when nowhere in Bs 7671 does it actually state the Ra must be stable. A max Zs of 1667 ohms is permitted, so in theory an Ra of Ra minus max R1+R2 value would comply with Bs7671.
I did note that an improvement would be beneficial but no code.
I've no intention of debating this as I'm immovable on it and have argued the case before on here.
Just interested in what code, if any, others might apply.

 

[buzzlightyear]

• I am sorry to hear of that. A very sobering experience no doubt. Could have been the unthinkable! Glad to hear you have survived such. Have you considered getting a check up? Harm can be caused which may not be apparent. Not trying to rustle up scare stories just that it may be possible to damage sensitive tissues around the heart and so on, maybe nothing but

  

  look behind you !

 

[elsparko]

if you dont carry a lockout kit disconnect the circuit at the board before working on it, not worth the risks, a "little shock" can burn your insides even when your skin looks fine, ive heard of guys having dead tissue under their skin when they look healthy enough after a shock

 

[Deleted member 9648]

By your reasoning above a C3 surely?

I've never looked at the regs as being the pinnacle of quality you should work to, more as them being the absolute bare minimum standard required. An earth impedance of several hundred ohms is grossly inadequate for noise suppressors and surge arrestors in any modern day power supplies or drivers. It would cause havoc with powerline ethernet adaptors and even poor quality sound from TV's and hi-fi's. Because of this I'd also inform the customer that whilst a better earth impedance isn't required by the regs it would be highly advisable to improve it because of a high liklihood of numerous future problems in other areas.

Indeed, I have banged in 2 coupled 4ft rods so it now goes down 8ft...result was a still rather high 160 ohms but an improvement. The thing is we are informed that the purpose of an EICR is to highlight non-compliances, and the original reading does comply hence no code. That said although the installation was satisfactory (code 3's were not addressed) an advisory letter has gone in with the report highlighting the poor earth and the presence of a 30ma RCD main switch and recommending a change to TNCS with RCBO's. Doubt they'll wanna spend the money though.

I am sorry to hear of that. A very sobering experience no doubt. Could have been the unthinkable! Glad to hear you have survived such. Have you considered getting a check up? Harm can be caused which may not be apparent. Not trying to rustle up scare stories just that it may be possible to damage sensitive tissues around the heart and so on, maybe nothing but....

No I haven't had a check up but you are probably right, I should've.

So there was no RCD anywhere?

There is a 30ma RCD main switch which did not operate, however I would hope that if the whack had been more severe and I'd got stuck on the voltage it would have done. As it was I let go instantly.

 

[littlespark]

Friday, I'm in pain!
I thought i'd write this post along the OP's thread. Similarly stupid.
Had been fitting downlights in a house, finished the job and started on a smoke detector circuit. I had to pull out the line of downlights i'd just fitted to ease running the cable across the ceiling. Was in a bit of a hurry, being Friday, so didn't take enough care.
When I pulled down the fitting, the springs closed quite sharply on most of my fingers.

Earlier in the day, i'd walked straight into a hanging loft hatch.... Twice

I just went home early.

 

[HappyHippyDad]

Carrying out a few minor remedials following an EICR on a small rented cottage this morning. One item was to replace the immersion heater stat for one with a thermal cut out. Switched off DP isolator alongside the tank, check with probes, crack on. Only trouble was the airing cupboard was a bit of a squeeze, and in manoeuvring around to get better access I managed to knock the switch back on with my elbow while having the live conductor in my other hand. Wrist in contact with the copper hot pipe on the top of the tank I got one hell of a poke, didn't half 'effin hurt. Had to have a bit of a sit down and contemplate, was working alone in an empty cottage, could have been the last EICR I ever done.
That's how it happens boys and girls, safe isolation every time with a moments thought for the unexpected before diving in. Lesson learnt....well 'till the next time anyway.
On another note, was a TT system with an Ra of 260 ohms, earth rod was in good condition with a 16.0mm main earth lead properly lugged to the rod.
I didn't code it because....
It complies with Bs 7671, which does not give a max value of Ra, the 200 ohms mentioned is only mentioned as possibly being unstable when nowhere in Bs 7671 does it actually state the Ra must be stable. A max Zs of 1667 ohms is permitted, so in theory an Ra of Ra minus max R1+R2 value would comply with Bs7671.
I did note that an improvement would be beneficial but no code.
I've no intention of debating this as I'm immovable on it and have argued the case before on here.
Just interested in what code, if any, others might apply.

Did it trip the RCD Wirepuller?
Just read further so no need to reply