Flourescent bench lamp

[Skywave]

O.K.; I wait to hear your result.

Al.

[Mark Hennessy]

Personally, I think that's the best solution as it eliminates the flicker from the tubes.

How noticeable flicker is is highly subjective, but I often notice the flicker from fluorescent tubes in my peripheral vision. For that reason, I have an electronic ballast in the lamp above my bench. I went for a dimable type, as I'm using a pair of 80 watt tubes (T5 types, 5 foot long) in a home-made fitting with a ballast bought from eBay for about £20. These are seriously bright, and the dimmer is rarely past 25%.

The downside of electronic ballasts is the RF interference. The general lighting in the workshop is provided by three 5 foot T8 fittings with conventional control gear, and I have a bi-pin angle-poise that is also standard. I'm planning to re-purpose some LED strips (found in a skip, thanks to ballast failure), and drive them with a linear PSU.

The other downside of electronic ballasts is the limited life expectancy, but it's usually capacitors failing that cause it. But at that price, it's hardly worth worrying - if it works well, buy a second and keep it somewhere safe

[pwdrive]

If doing DIY for LED's that give decent illumination eg: higher power LED's then don't use a dropping resistor to feed them, looking at the VI curve for one will show the reason why, constant current with over current limiting is what's needed.

Lawrence.

[Refugee]

I have been looking into replacing the control gear in a strip light and was thinking of a copy of what I have seen in modern commercial buildings.
They look like two chains of 70 normal white LEDs with silicon diodes in series with each chain wired in inverse parallel and a single resistor.
There used to be a type of Luxon Star that had the chip internally wired like this and I have some lights that have been converted to these. They do need a heat sink though.

[Radio Fixer]

Well modified for electronic ballast and very good it is to. Virtually instant start and no flicker. It actually seems brighter as well. Electronic ballast pretty small.

Figures on the 'mains meter' are : 247 V, I = 0.11 A, W = 15, VA = 26, PF = 0.51

And some pics

   
   
   
   

I will take Mark's advice and buy a spare ballast, to go with the spare tube and all the lamps, mostly now obsolete to modern fittings !

Gary

[pwdrive]

I like the time recorder, 7 mins to 3.

Lawrence.

[Radio Fixer]

Oh! and another advantage: there is no audible hum that it used to have from the chokes.

Gary

[AlanBeckett]

And you've got three Chokes left over. Can't be bad

Alan

[Nick]

I've slowly replaced the ballasts on the few fluorescent lamps we have with electronic equivalents - fish tank, magnifying desk kamp etc...

It's a really simple mod and as the electronic ballasts are generally smaller, installation is easy.

As has been pointed out, less noise and heat, seemingly better startup but still a lousy power factor though on the scale of domestic power usage, not that important...

[Skywave]

As has been pointed out, less noise and heat, seemingly better start-up but still a lousy power factor, though on the scale of domestic power usage, not that important...

You forgot to mention . . .

The downside of electronic ballasts is the RF interference.

And for me, that rules out their installation in my radio shack / workshop.

Al.