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philthespark · 19th Jun 2020, 7:18 pm

there are still legitimate uses for a neon tester and no other tester will work and that is when testing polarity on a TNCS incomer!
As the neutral and earth only split inside the service head you cannot test between live and neutral and then live and earth to confirm that the live is actually live and not the neutral,in fact there's a tool called a Testoscope for this, basically it is a neon screwdriver but the end hasn't got a screwdriver blade,just a point.
I've been in the industry for over 30 years and this is the only time I would use a neon tester. I've seen them light on a cable that was cut at both ends,purely to induced voltage in the cable I've seen them not light when on a known live because the user had rubber soles on his shoes and was standing on a wooden floor, but the worst one was when an apprentice dropped one in a sink full of water,he dried it off and put it back in the toolbox without saying anything. The electrician got a nasty belt shortly after when he used it to test a ceiling rose.
That said it is a bit like test prods on meters and such GS 38 states they must have no more than 3mm of bare metal showing, that's dangerous at times, I've seen sparks thinking the item they are working on is dead but it turns out the tip of the prod hasn't made contact with the terminal. I like a good 10mm of metal exposed, if you can't handle a probe safely then in my opinion you have no business working on the stuff.
I totally agree with Russel regarding touching stuff as an AP, in my job I quite often have to isolate kit for a strip out and I always, after making sure it is dead, make a point of showing the other workers that it is dead by touching the cables at the terminals, as he said, it gives them confidence in you.
Recently I was working on a third rail system on a certain underground railway, now it runs at 750v and there are two types of tester for this, one is known as the CRID, or current rail indicating device, used to be known as a 'box of eggs', this is 2 boxes with handles that are placed one on the track rail and the other on the conductor rail, perfectly safe. The other is a pair of black tubes about 20mm in diameter with a cable between them, in the end of one are 3 leds. Partway down on each tube is a large plastic collar, this stops you slipping a hand down and contacting the live rail, not a good idea. Anyway we're on this job and the electrical supervisor from the rail company comes down toprove the rail dead, he then pulls an ordinary Fluke tester out of his pocket to test with! Now ok the Fluke will handle the voltage no issues, but he has zero protection if his hand slips, what an idiot.

19th Jun 2020, 7:18 pm	#55
philthespark Pentode Join Date: Oct 2017 Location: Newton-le-Willows, Merseyside, UK. Posts: 158	Re: Neon Tester Screwdrivers there are still legitimate uses for a neon tester and no other tester will work and that is when testing polarity on a TNCS incomer! As the neutral and earth only split inside the service head you cannot test between live and neutral and then live and earth to confirm that the live is actually live and not the neutral,in fact there's a tool called a Testoscope for this, basically it is a neon screwdriver but the end hasn't got a screwdriver blade,just a point. I've been in the industry for over 30 years and this is the only time I would use a neon tester. I've seen them light on a cable that was cut at both ends,purely to induced voltage in the cable I've seen them not light when on a known live because the user had rubber soles on his shoes and was standing on a wooden floor, but the worst one was when an apprentice dropped one in a sink full of water,he dried it off and put it back in the toolbox without saying anything. The electrician got a nasty belt shortly after when he used it to test a ceiling rose. That said it is a bit like test prods on meters and such GS 38 states they must have no more than 3mm of bare metal showing, that's dangerous at times, I've seen sparks thinking the item they are working on is dead but it turns out the tip of the prod hasn't made contact with the terminal. I like a good 10mm of metal exposed, if you can't handle a probe safely then in my opinion you have no business working on the stuff. I totally agree with Russel regarding touching stuff as an AP, in my job I quite often have to isolate kit for a strip out and I always, after making sure it is dead, make a point of showing the other workers that it is dead by touching the cables at the terminals, as he said, it gives them confidence in you. Recently I was working on a third rail system on a certain underground railway, now it runs at 750v and there are two types of tester for this, one is known as the CRID, or current rail indicating device, used to be known as a 'box of eggs', this is 2 boxes with handles that are placed one on the track rail and the other on the conductor rail, perfectly safe. The other is a pair of black tubes about 20mm in diameter with a cable between them, in the end of one are 3 leds. Partway down on each tube is a large plastic collar, this stops you slipping a hand down and contacting the live rail, not a good idea. Anyway we're on this job and the electrical supervisor from the rail company comes down toprove the rail dead, he then pulls an ordinary Fluke tester out of his pocket to test with! Now ok the Fluke will handle the voltage no issues, but he has zero protection if his hand slips, what an idiot.