evening alli know its a no no to use a neon screwdriver to test but im not 100% sure why this is. the reason i ask is that ive been to check out a faulty light, when i got there he said he'd check for power with his tester (neon) and it lit up, i recommend he didnt use it for that but more for a screwdriver and he asked why? i blagged it, but would like to know the reasons for next time.
thanks wayne
Excluding all the 'fail safe' 'fail dangerous' points that the other guys have already debated quite admirably..
Lets assume you have a good working Neon.
AND it IS a type that will fail safe..
It is still unreliable because of the "brightness question"
a] You need to ask yourself:-
(i) What Voltage does the neon require in order to illuminate?
(ii) What voltage is considered to be safe, and thus at what point does a
voltage become hazardous?
How do you know what you are reading with a neon?
{Spec Loc scientific test method coming up......
]
:coat}
b] How can any item of safety test equipment be conditional upon what you are wearing!
METHOD
- Wire yourself up a little light switch dimmer circuit with a suitably accessible live part on the load side. Plug it in, in a garage or room with a concrete floor.
- Take your boots off test the circuit with your neon whilst standing on the concrete floor in just your socks
- Twiddle the dimmer up and down a bit watch how the brightness off the neon changes.
- Do the above two points again.. but this time whilst wearing your "approved safety shoes", those with 1000v rated insulated soles, (NOT trainers, proper safety boots).**
- If you are really keen, you could also do the test whilst standing on fibreglass insulated step ladders! :|
- Try all of the above again in a environment with high ambient background light and/or bright sunshine!
CONCLUSIONS
Compare the difference with the "apparent glow" of the neon, which varies depending upon what you are wearing or what you are standing on! Thus the Neon is an inconstant measuring device that cannot provide a reliable safe/dangerous voltage level indication.
If you try the same tests with an approved meter or voltage tester incorporating a voltage level indication, shoes socks, floor contact has NO effect upon the results you read off the meter.
{** as a side point do an insulation resistance test on the sole of proper safety boots compared to trainers, note the difference in conductivity}