andy_spark
Senior Member
Called out because a mate's step father got a shock off the landing switch, and the RCD tripped. Mother was panicking. rightly so as it turned out....
First look in the CU revealed the CPCs on both lighting circuits were cut short and not connected. Why???
Dual RCD board approx. 10-15 years old, looking like the earths had never been connected since CU swap.
The lighting circuits were also incorrectly identified.
Both RCDs tested correctly under all fault conditions.
With power off an IR test showed 0 ohms between L & E on first floor lights.
With power on this was occurring,!!! No wonder the old man got a shock!
![Screenshot_20230126-105710_Video_Player[1].jpg](https://cdn.imagearchive.com/electricianforum/data/attachments/10/10774-6cbf759d7e2b90b6f35723ad5aa80b72.jpg "Screenshot_20230126-105710_Video_Player[1].jpg")
Ground floor lights had good IR results, R2 test was good and after extending and connecting the cpc to main earth bar, powered up.
To compound matters there was reverse polarity at the pendants on the first floor. This fault was traced back to the live feed up toythe 1st floor lights in the airing cupboard where at some point a JB had been used to join the cable with this unusual approach to sleeving.... The actual fault to be found was N-E short but due to reverse polarity was showing as L-E.
Someone (allegedly an electrician) had in the last couple years fitted some brushed steel switches and sockets.
About three years ago a new bathroom was fitted and the owner wondered why the bathroom fitter hadn't picked up on any issues..
I politely pointed out he was bathroom fitter, and had happily left a 6 inch pendant dangling rather close to the shower enclosure.
After further testing of the lights, I established the fault lay somewhere after another jb supplying an old FCU in the loft, which in turn was feeding onto the loft conversion lights.
I disconnected all this and powered up the now properly connected and tested lighting circuit. Back next week to hopefully sort the rest and fit an IP44 bathroom light, plus replace the metal switches for white plastic!
Really makes you wonder what standards some people are happy to work to!
First look in the CU revealed the CPCs on both lighting circuits were cut short and not connected. Why???
Dual RCD board approx. 10-15 years old, looking like the earths had never been connected since CU swap.
The lighting circuits were also incorrectly identified.
Both RCDs tested correctly under all fault conditions.
With power off an IR test showed 0 ohms between L & E on first floor lights.
With power on this was occurring,!!! No wonder the old man got a shock!
Ground floor lights had good IR results, R2 test was good and after extending and connecting the cpc to main earth bar, powered up.
To compound matters there was reverse polarity at the pendants on the first floor. This fault was traced back to the live feed up toythe 1st floor lights in the airing cupboard where at some point a JB had been used to join the cable with this unusual approach to sleeving.... The actual fault to be found was N-E short but due to reverse polarity was showing as L-E.
Someone (allegedly an electrician) had in the last couple years fitted some brushed steel switches and sockets.
About three years ago a new bathroom was fitted and the owner wondered why the bathroom fitter hadn't picked up on any issues..
I politely pointed out he was bathroom fitter, and had happily left a 6 inch pendant dangling rather close to the shower enclosure.
After further testing of the lights, I established the fault lay somewhere after another jb supplying an old FCU in the loft, which in turn was feeding onto the loft conversion lights.
I disconnected all this and powered up the now properly connected and tested lighting circuit. Back next week to hopefully sort the rest and fit an IP44 bathroom light, plus replace the metal switches for white plastic!
Really makes you wonder what standards some people are happy to work to!
