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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> Trouble with neon indicator lights https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1479153255 Message started by tony2345 on Nov 14^th, 2016, 7:54pm

Title: Trouble with neon indicator lights
Post by tony2345 on Nov 14^th, 2016, 7:54pm

None of the neon indicator lights on my power circuit work. That is on 2 connector units, one double pole switch and a trailing socket. Nor does the neon light on the separate cooker circuit.

Have these all died or is there something wrong with the wiring? They have not worked for years - I cannot remember whether any of them did work originally.

Title: Re: Trouble with neon indicator lights
Post by Lectrician on Nov 15^th, 2016, 6:19am

I would say they're faulty.

Title: Re: Trouble with neon indicator lights
Post by CWatters on Nov 18^th, 2016, 4:57pm

That got me looking at the neons in a pair of extension leads I've had powered up for about 5 years - both have "failed".

Google says the expected lifetime is "years" but it depends on the current put through them. That in turn depends on the series resistor used with them.

Apparently material is given off by the electrodes and this coats the inside of the glass so eventually the light can't escape. You can't clean it off as they are sealed.

This application note..

http://static.vcclite.com/pdf/Neon%20Application%20Information.pdf

..says that a high brightness neon can be expected to loose half it's brightness in 8000 hours (about a year) and a standard brightness bulb in 25,000 hours (under 3 years).

Title: Re: Trouble with neon indicator lights
Post by Natedog on Jan 12^th, 2017, 6:51pm

you can massively increase the lifespan by putting a slightly higher value resistor in series with them, and still have surprisingly little effect on the light output