LED tube to replace fluorescent tube in existing batten

[Ihavenojob]

Is there a direct LED replacement for a fluorescent tube which negates the need to replace the whole batten? They're 4ft ones.

 

[markyd1]

4ft 18w LED Fluorescent Tube - White - 2165lm. | LEDlite (LTT418W)

Click on link

 

[ericmark]

It does depend on what start method is used by the old fluorescent, if the ballast is wire wound then the you change the starter for a fuse normally supplied with the new tube, and simply put in the LED tube.

If the start method uses an electronic ballast, then internals need re-wiring to get rid of the ballast completely.

A 4 foot fluorescent tube will normally use around 36 watt and give 3350 lumen, so around 93 lumen per watt, @markyd1 has linked to a LED version 18 watt and 2165 lumen, so 120 lumen per watt. So it uses 22.6 % less watts per lumen, but advert says "Energy Saving up to 85%" clearly they are not very good at maths. Price £9.24 when an fluorescent tube costs £1.90 the fluorescent average life 20,000 hours, the LED 3 years (26,280 hours if run 24/7) or 30,000 hours.

However for a fluorescent tube the lumen and life is given based on a wire wound ballast, when using a HF or electronic ballast life is longer and lumen per watt is better, so when using an electronic ballast there is very little in it.

This wiring diagram

for the electronic ballast is dangerous, as the tube has supply to one side, and short circuit the other side, so if put in wrong way around it is a short circuit, also if the magnetic ballast is left in place, it reduces the power reaching the LED tube, so although it may use 18 watt, it is likely not at 230 volt, but a lower voltage so amps go up, so with ballast left in place as a whole unit it uses more than 18 watt.

 

[winston1]

Basically if you replace a florescent tube with an LED it will use less power and give less light. So you may need additional lighting to make up which will of course bring the energy use and cost back up.

 

[SUNRAY]

Basically if you replace a florescent tube with an LED it will use less power and give less light. So you may need additional lighting to make up which will of course bring the energy use and cost back up.

Thank heavens I'm not the only one who has come to this conclusion. Having said that my experience is based on customers asking to restore their LED tubes back to flou.

 

[Ihavenojob]

Thanks for the replies. Looks like I may as well just replace the fluorescent tubes.

 

[SUNRAY]

Thanks for the replies. Looks like I may as well just replace the fluorescent tubes.

Regardless of what makers claim LED tubes do not provide the same even light coverage as fluo tubes.

 

[FrodoOne]

Regardless of what makers claim LED tubes do not provide the same even light coverage as fluo tubes.

Maybe so.

However LED tubes produce the light mainly in one direction - downwards (or "outwards").
Florescent tubes produce light in 360 degrees and most of the "Upwards" light (at least 30 %) is wasted, unless the reflector above is very "efficient" - as in a "mirror" - which is not a likely possibility.

Hence the "less bright" LED tubes produce most "light" in the direction where it is required.

 

[ericmark]

With a wire wound ballast the LED is a good option, as the wire wound ballast is very dependent on voltage, too little it will not strike, and too much is uses well over what is written on the tube.

But we stopped selling wire wound some time ago, and the electronic ballast uses just enough, and has a larger voltage band.

The tubes are not all the same, I linked to a triphosphor, some have reflectors built in, the same applies to LED some have less lumen per watt to the fluorescent but the one @markyd1 linked to is rather good, the 5 foot I had was 24 watt and 2200 lumen so no better than fluorescent.

As to life, the old fluorescent 65 watt would last 4 to 6 years in the wire wound ballast, the 58 watt thin tubes that replaced them would last around 2 years, until solar panels were fitted local, then at some times of the day they would not start.

The first LED lasted around 18 months, and unlike the fluorescent which would flash and flicker giving some warning, it worked one day then not the next, since re-wired the fitting could not easy revert to fluorescent so second LED fitted, it did not fail, son bought that house and replaced with GU10's the old tube still in my garage.

I seem to remember new rules say must be 75 lumen per watt or better, many LED bulbs are being sold off cheap as they don't comply.

 

[SUNRAY]

Maybe so.

However LED tubes produce the light mainly in one direction - downwards (or "outwards").
Florescent tubes produce light in 360 degrees and most of the "Upwards" light (at least 30 %) is wasted, unless the reflector above is very "efficient" - as in a "mirror" - which is not a likely possibility.

Hence the "less bright" LED tubes produce most "light" in the direction where it is required.

Which is why I've returned so many LED tubes to fluo when the customers complain of dark patchy illumination.
I'm sure the tubes will/are morphing/improving with time.

 

[ericmark]

The main problem is the electronic ballast when removed needs a re-wire like this

This means it does not matter which way around the tube is placed, and the fuse replaces the starter so if some one fits a fluorescent instead of a LED it simply blows the fuse, as two heaters will not take 230 volt they need the ballast to reduce the current/voltage at the starters.

But the main problem is tubes like this one are not much better than fluorescent lumen per watt, and only produce 1600 lumen.

OK only 16 watt, and in a corridor we did tend to use OTT lighting to cover the length, so the reduction in light output is OK, but in a kitchen, we want the light, so my old house had 2 x 65 + 58 watt fluorescent lamps, set in a T shape, to lights both the original and extension, my son has removed them and moved to LED down lights, around 30 of them, at 3 watt each, so there is a reduction 123 watt down to 90 watt, if he says at 3 watt each. But he tends to buy what is on offer so likely will end up as 3.6 watt, and with the example shown, 108 watt at 10350 lumen where the original was 123 watt at around 10400 lumen, so as near as you can get same, except the LED lamps cost £67.47 and the fluorescent £10.44 they have gone up in price.

 

[flameport]

Looks like I may as well just replace the fluorescent tubes.

That, or replace the whole fitting for a new LED one. Example: https://www.cef.co.uk/catalogue/products/4837543-35w-4ft-led-steel-batten-fitting-4000k which is brighter than the same length fluorescent tube and approximately the same power (35W compared to 36W + ballast losses). It also starts at full brightness unlike the fluorescent version so will appear significantly brighter in applications where the lights are switched often and used for short periods.

A lower power 17W version is available, obviously that is significantly less bright but whether that is suitable depends on how much light is actually required.

Shoehorning 'LED tubes' into an existing fitting that was designed for fluorescent tubes is total nonsense and is very far from optimal.

 

[SUNRAY]

Shoehorning 'LED tubes' into an existing fitting that was designed for fluorescent tubes is total nonsense and is very far from optimal.

Even though some of the LED fittings are identical to some Fluo fittings?

 

[SUNRAY]

The main problem is the electronic ballast when removed needs a re-wire like this View attachment 278736This means it does not matter which way around the tube is placed, and the fuse replaces the starter so if some one fits a fluorescent instead of a LED it simply blows the fuse, as two heaters will not take 230 volt they need the ballast to reduce the current/voltage at the starters.

But the main problem is tubes like this one are not much better than fluorescent lumen per watt, and only produce 1600 lumen.

OK only 16 watt, and in a corridor we did tend to use OTT lighting to cover the length, so the reduction in light output is OK, but in a kitchen, we want the light, so my old house had 2 x 65 + 58 watt fluorescent lamps, set in a T shape, to lights both the original and extension, my son has removed them and moved to LED down lights, around 30 of them, at 3 watt each, so there is a reduction 123 watt down to 90 watt, if he says at 3 watt each. But he tends to buy what is on offer so likely will end up as 3.6 watt, and with the example shown, 108 watt at 10350 lumen where the original was 123 watt at around 10400 lumen, so as near as you can get same, except the LED lamps cost £67.47 and the fluorescent £10.44 they have gone up in price.

I've just realised a confusing error in that drawing

 

[ericmark]

I've just realised a confusing error in that drawingView attachment 278921

The LED replacement for starter is really a fuse. So not really an error.