Temperature of under-cupboard fluorescent fittings?

[Mathew J. Newton]

I recently fitted four 8W T5 under-cupboard fluorsecent 'cabinet link-lights' manufactured by Eterna (pg. 17 of their 1MB catalogue at

in my kitchen.

Having not been impressed by the colour of the light I replaced the supplied 'standard' tubes with Osram Interna Lumilux tri-phosphor tubes with a filament-matching temperature of 2700K. The light output is now superb, both in terms of colour rendition and matching of the other lamps in the kitchen (filament and a cooker hood halogen).

However, my only gripe is with the heat that the light fittings give off - not so much the tubes themselves but rather the actual fitting. Indeed the casing becomes too hot to touch with the consequence of some heating of the cupboards above.

Knowing nothing about fluorescent technology I did some searching of past posts, and some other Internet publications, and now realise that given my fittings are quite heavy and have a 'standard' starter poking out of the back they thus are not 'electronic'? Thus, they use a standard choke inside which is creating all this heat? Are they also inefficient? The fittings are labelled as 'energy saving' however..

My question (finally!) is thus: What are my chances of being able to (cheaply) convert these fittings to electronic ballasts/starters? Would the guts of true slimline (slimline = must be electronic?) fittings (e.g. those from TLC at

be transferrable? If so, which wattage would I need (mine are 8W)?

Alternatively, would I be best just ditching my current setup in favour of the TLC items above (which would also provide flicker-free startup)? I do REALLY like my current 2700K output, however, so would the 3400K (still tri-phosphor) TLC tubes be noticeably different? If so, does anyone know where I could get hold of 2700K T4 tubes in the TLC lengths?

Questions questions...

Mat

[Mathew J. Newton]

I recently fitted four 8W T5 under-cupboard fluorsecent 'cabinet link-lights' manufactured by Eterna (pg. 17 of their 1MB catalogue at

in my kitchen.

Having not been impressed by the colour of the light I replaced the supplied 'standard' tubes with Osram Interna Lumilux tri-phosphor tubes with a filament-matching temperature of 2700K. The light output is now superb, both in terms of colour rendition and matching of the other lamps in the kitchen (filament and a cooker hood halogen).

However, my only gripe is with the heat that the light fittings give off - not so much the tubes themselves but rather the actual fitting. Indeed the casing becomes too hot to touch with the consequence of some heating of the cupboards above.

Knowing nothing about fluorescent technology I did some searching of past posts, and some other Internet publications, and now realise that given my fittings are quite heavy and have a 'standard' starter poking out of the back they thus are not 'electronic'? Thus, they use a standard choke inside which is creating all this heat? Are they also inefficient? The fittings are labelled as 'energy saving' however..

My question (finally!) is thus: What are my chances of being able to (cheaply) convert these fittings to electronic ballasts/starters? Would the guts of true slimline (slimline = must be electronic?) fittings (e.g. those from TLC at

be transferrable? If so, which wattage would I need (mine are 8W)?

Alternatively, would I be best just ditching my current setup in favour of the TLC items above (which would also provide flicker-free startup)? I do REALLY like my current 2700K output, however, so would the 3400K (still tri-phosphor) TLC tubes be noticeably different? If so, does anyone know where I could get hold of 2700K T4 tubes in the TLC lengths?

Questions questions...

Mat

[Andrew Gabriel]

No -- T5 and T4 lamps almost certainly run at different currents. The control gear inside those slimline T4's is normally just a bare circuit board, which is not going to easily mount inside a metal lamp. Instead, buy the proper T5 control gear. Philips make a range of 'Matchbox' ballasts, and RS stock some of them. The one you want is RS part number 397-0255 which is the instant start version (RS don't stock the preheat versions).

(I'd give you a pointer on the RS website, but it's too clever to let me do that:-(.

T4 tube lengths are not standardised. You have to use replacements from the manufacturer of the fittings.

CPC do the Omicron range which come with 2700K tubes in a variety of lengths, with or without individual switches (and Maplin do one of the sizes too, but more expensive).

[Mathew J. Newton]

That's great - many thanks... It looks like they're just the ticket. I trust they should run cool(er)? Would they also offer any advantage with regards to tube life? Can you tell me the difference (pros/cons?) between instant-start and preheat?

startup)?

I saw one of your old posts suggesting these however I note that CPC appear to be no longer stocking the range (or at least have very limited stocks). Their suggested alternative (e.g. LA02262

doesn't specify the colour temp (merely 'Warm White' which, I've found whilst hunting for lamps, can seemingly mean quite a range).

Thanks again for your help; it's appreciated.

Incidentally, I took a few measurements inside my cupboards today and whilst the air temp inside rose from ~18C to ~20C the temperature immediately above the ballast rose to ~30C!

Mathew

[Andrew Gabriel]

In theory, the instant start ones will give shorter tube life if they are frequently switched on and off. Probably better than than using magnetic ballasts and starters even so.

Hadn't noticed that. You might like to contact Omicron and ask them who stocks their range now. Maybe that range no longer exists.

[Mathew J. Newton]

Would you believe it; I was all set to order the Philips electronic ballasts and re-engineer mine fittings when I thought I'd pop in to Focus on my way home as I'd heard they'd got some under-cupboard lighting that I hadn't seen.

In there I found some ultra-slim fluorescents with electronic ballasts

They took the foot-long T5 8W tubes thus allowing me to swap in the Lumilux 2700K ones I already had... which is a good thing too - the supplied tubes were a horrific

6400K - they looked dreadful!!

Given they only cost =A38 each I went for them. In use they're considerably cooler and flicker free - both in startup and use so I'm pretty happy now. Will have to stick my others on eBay as I'm sure they'll be of use for someone.... incubator perhaps?! ;-)

Thanks again for your help; I'll certainly remember the recommendations for the future.

Mathew