If you like T4 which isn`t a standard and lamps can be pretty variable, you`ll love T5, T 5/8" , is a standard, good range of colours , very efficient and easy concealed straw of light, Ballasts tend to be pricey though, its a comercial rather than domestic fitting but they will last and they won`t dim to zero very well.
Cheers Adam
Ebay is a good source for T5 ballasts. I used to buy from Farnell, but they stopped stocking the ones I used, and ebay is better value anyway.
If you like T4 which isn`t a standard and lamps can be pretty variable, you`ll love T5, T 5/8" , is a standard, good range of colours , very efficient and easy concealed straw of light, Ballasts tend to be pricey though, its a comercial rather than domestic fitting but they will last and they won`t dim to zero very well.
Cheers Adam
Thanks: Though puzzled, I never did get round to looking up the differences. Screwfix not very good at explaining: but not always offering a choice anyway.
S
Did you consider the Bell G9 adapters, not quite as white as LV but an easy retrofit?
Cheers Adam
Added sci.engr.lighting where sure someone will be able to give the comprehensive answer.
In practice , dunno where T4 came from, 1/2" diameter lamp, every maker of the fittings uses their own length , makes lamp and ballast pretty disposable and not always long lived.
T5, is a proper standard with lamps and fittings from loads of makers, its very efficient , knocking halogen inrto the weeds but yet to see a T5 spolight ;-)
When say colours , mean variants of white , from warm to cold and some with very good colour rendering.
Ballasts mainly being made for commercial market are generally rated to 50K hours, lamps typically 20K+.
A glance on ebay could be illuminating.
Cheers Adam
Osram brought out its FM (T2) tubes, which I was quite looking forward to making use of in cabinet and under cupboard lighting applications, but they were expensive. Then all the T4 products seem to appear from China at very reasonable prices, and basically killed the Osram FM, and also undercut the T5HE lamps, so they have not yet made any serious inroads into the residential market in UK.
Someone in the US in sci.engr.lighting might comment, but my impression is that the Chinese T4 products mostly got aimed at Europe, rather than the US. They are now very popular here in the UK because they're very cheap. As you say, there's no standardisation/interchangability between manufacturers, and I'm in the process of retiring one set because the tubes are no longer available (and replacing with T5HE and T5HO). However, since the T4 fitting plus tube cost only very slightly more than a CFL at the time, I haven't lost out financially, just the inconvenience.
There are lots of commercial T5 fittings with well defined and bounded light distribution patterns. The use of smaller T5 (rather than larger T8 or T12 tubes) makes it possible to design luimaire optics to more presicely direct the light exactly where it's wanted (a smaller light source is more controllable).
The smallest of the newer T5HE's is the 14W which is appox an inch longer than the largest of the old T5's (13W). However, the distinction between these two ranges is now blurred because the old T5's are now also available as triphosphor tubes (as well as the original halophosphate tubes), and the triphosphor tubes can be thought of as an extension of the T5HE range downwards. Indeed, some lighting manufacturers are producing ranges of fittings which straddles both these tube ranges.
You'll struggle to find lower than 3000k with T5 (e.g. 2700K to mix with filament lighting). However, you can usually increase the illuminance level when moving to T5 such that 3000k or higher still looks natural in the home (lookup the Kruithof curve).
We've got just short of 100K hours (10 years) from our original electronic ballasts in my building at work. Most common failure mode is breakdown of the PCBs, followed by burnout of the transformer windings (I guess a shorted turn). I would hope current (new) ballasts would be no worse longevity, and they tend to run cooler than the 10 year old ones did. (Of course, none of these come close to longevity of simple switch-start ballasts. ;-)
Yes, but I don't see G9 surviving long term - too inefficient, and not much better than existing mains filament lamps which are already being phased out. (The whole reason for the change is because of the phasing out of mains filament lamps - I don't want to change for something that may only last a few extra years.) At least the 12V filament lamps are around twice as efficient, and will probably exist for longer.
Thanks to you both. The ballast in our strip lights and in ordinary cfls looks similar to me - just spread out in the tubes mounting. Those that I have opened on failure usually have the same large capacitor, and this is often fried. I bought some physically larger caps, and repaired a few of the ballasts, but getting at them is not easy, so I have 'lapsed' into junking them lately as prices have come down. There is also a hidden fuse on the ballast, which is v annoying: seems a terrible waste chucking all this stuff away. The other thing with the strips is that the manufacturer changes the linking plug design a couple of times a year, so replacements can never be linked in without cutting off the connectors and using an ordinary block.
S
"There is also a hidden fuse on the ballast" -- Is it a fuse or thermal cutoff? I don't know what the practice is in the U.K. but, if the device is a thermal cutoff, then an overheated or failing ballast cycles on and off due to temperature which gives an indication of what's going on.
Terry McGowan
IME, they contain both. The fuse is there to protect against a component failure on the primary side. The ballasts are not intended to be repairable items, so the fuse isn't replaceable. If you are choosing to repair a ballast (which I've done too), then you can replace the fuse too, but you take on the safety responsibility for the ballast from that point on. The fuse is most unlikely to blow without some other fault in the ballast.
I've not tried exercising the thermal protection in ballasts, so I don't know if they are self-resetting or one-shot. It's usually a part clipped to one of the switching transistors. In LV lighting transformers, the thermal protection is normally self-resetting, and can result in cycling on and off.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.