Thorn SRS 6ft Fluorescent fitting problem

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danielsheld
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Thorn SRS 6ft Fluorescent fitting problem

Post by danielsheld » Wed Jul 13, 2016 12:20 pm

Hello,

I have a Thorn 6ft SRS fluorescent fittings. Recently the old T12 Omega daylight tube has gone, so i have replaced it with a T12 philips MCFE 840 tube. However the new tube doesn't seem to start correctly often when you switch it on the tube starts instantly (rather than fading in as i believe they should on srs) and other times it fails to start and you have to flick it on and off (Much like when you put a T8 tube in).

The phillips tube is brand new and works fine on switch start.

Anyone have any ideas?

Thanks a lot

Daniel

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LinearSLI-H
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Re: Thorn SRS 6ft Fluorescent fitting problem

Post by LinearSLI-H » Wed Jul 13, 2016 9:30 pm

MCFE tubes are coated with a transparent water-repellant silicone coating which prevents the formation of a continuous film of water on the glass.
On starterless circuits the starting voltage is dependant on the electrical resistance of the glass surface and is at its weakest when this resistance is either very low, or very high, the coating brings about a high resistance to starting, which is the reason you have problems with it starting every now and then.
FEED THE MOOMIN!!

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Paul
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Re: Thorn SRS 6ft Fluorescent fitting problem

Post by Paul » Wed Jul 13, 2016 9:42 pm

Spot on sir! :D

danielsheld
Posts: 5
Joined: Tue Aug 04, 2015 11:05 pm
Favourite Manufacturer: Thorn
Area of interest: Fluorescent
Oldest item: Thorn SRS 75w Light Fitting

Re: Thorn SRS 6ft Fluorescent fitting problem

Post by danielsheld » Thu Jul 14, 2016 10:42 am

Many thanks for your reply, I have since opened the fitting up and discovered the earth wasn't connected very well which has improved starting quite a bit.

Just out of interest in what situation would you use MCFE tubes over standard ones then, just in areas prone to moisture?

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LinearSLI-H
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Oldest item: Philips 160W MBT/U 1951
Location: Cheshire

Re: Thorn SRS 6ft Fluorescent fitting problem

Post by LinearSLI-H » Thu Jul 14, 2016 7:54 pm

MCFE are the standard fluorescent tube :)
FEED THE MOOMIN!!

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