New to LED tape - for an upcoming install

[Jamtastic3]

Hi BR,

So I've been asked to under light a bar front.

The first thing I thought was a cheap ropelight, but this will burn out eventually in places. So now I turn to LED tape but I'm new to the stuff.

 

I'm looking to put in red LED tape, no RGB or DMX required, just a simple off and on to give the bar a nice red underlit look. But what do I need and how is it all set-up? I'm guessing a transformer has to come into it somewhere...

Any directions to ideas and products would be great from people who've used LED tape or installed it before.

 

 

Cheers!

[Ynot]

Seen a lot of bars using EL wire, though not sure whether it would be big/bright enough for you.

[hadyn.williams]

The last lot I used was for lighting inside display cabinets, so I imagine it's the sort of stuff you are after...

 

The product was basically sticky back'd flexible tape with white LEDs spaced about 1 inch apart. It came from CPC (so maybe speak the Chirs Beesley)and was supplied on drums. It could be cut every foot or so and either soldered to another strip or connected to a transformer. We used 12V transformers, although they could be run on 9v and was slightly dimmer.

 

Oh, and it cost about £40/m....

 

PM me for any photos or if you are interested in hiring some strip.

 

HTH

[Chris Beesley]

Have a peek here .... http://www.led-lites.co.uk/

[musht]

You want rigid or flexible, if flexible which way?

waterproof or not bothered?

Price varies by density usually quoted at LEDs per m , 30 per m upwards usually for flexible tapes. Go a lot higher density in rigid.

Most flex tapes are smd wide angle LED which is short throw, <500mm. Rigids cn use more focused LEDs with greater density and longer throw.

Need a 12V D.C. LED driver or regulated low current source not an L.V. lighting trafo someat like

http://www.screwfix.com/prods/85503/Lighti...0DRIVER-_-85503

[sleah]

Alternative supplier, they do both flexi and rigid in variety of colours. Site shows prices too :)

 

I've used them myself, no complaints although delivery can be up to two weeks, but it does say so -_-

 

Led Depot

[osal]

your local maplin should do it however they can be pricy from maplin but they might be able to give you a demo so you can see what they look like

[boswell]

Put +led tape into a google UK search, it might help -_-

[Jamtastic3]

Put +led tape into a google UK search, it might help -_-

 

Yes yes I did :).

I'm more needing scope into how to set it all up, like what kind of transformers I need for what tape, how much power for how much tape used, how far a distance the transformer can be to the tape. There's not much I could find that told me the 'how to' basics. Flexible or rigid LED tape (depending on prices) is what I'm looking for.

 

I also went to the place where they want the bar lit and now they want a couple section of walls lit from a lip that goes along the ceiling. I'm guessing the main section is around 10 to 12 metres long but haven't done exact measurements yet. The bar is 5 metres long.

 

So yeah more info would be good but thanks for the replies so far.

[boswell]

The max run of Leds fed from a single point ie the run of tape is fed from 1 end, seems to be about 5 mtrs. (Due to volt drop along the tape).

Centre fed you can have a total of 10 mtrs.

You will need a either DC supply or a transformer&Bridge rectifier combination, power rqd depends on the number of LED so look at the spec of the strip, but it will be very small. Most strips require 12vDC, so I tend to use bog standard 60VA or 105VA 12v lighting transformers (as used for MR16s). If the strip is a bit too bright, stick a couple of diodes in series with one leg, each diode will drop about 0.7V. You do not need expensive constant voltage or constant current powerpack/LED drivers.

HTH

[musht]

You do not need expensive constant voltage or constant current powerpack/LED drivers.

HTH

 

Made good money out of people who have thought the same ;-)

[timsabre]

You will need a either DC supply or a transformer&Bridge rectifier combination, power rqd depends on the number of LED so look at the spec of the strip, but it will be very small. Most strips require 12vDC, so I tend to use bog standard 60VA or 105VA 12v lighting transformers (as used for MR16s). If the strip is a bit too bright, stick a couple of diodes in series with one leg, each diode will drop about 0.7V. You do not need expensive constant voltage or constant current powerpack/LED drivers.

HTH

 

Umm, really? If you want good life out of the LEDs I disagree. To drive the LEDs at their rated current you need to get reasonably close to 12V which generally means a regulated (constant voltage) supply. A transformer and bridge rectifier will vary a lot depending on load, also if you don't smooth it with a capacitor it will be noticeably flickery.

 

12V MR16 lighting transformers generally produce a high frequency AC output, not DC, which is not going to do the LEDs any good unless you put a blocking diode in, and again the voltage is quite variable depending on load.

 

To avoid premature failure or dimming of the LEDs, you should use a 12V DC regulated power supply.

[boswell]

To avoid premature failure or dimming of the LEDs, you should use a 12V DC regulated power supply.

 

There speaks someone who is trying to justify using expensive powerpack.

 

A MR16 type transformer (or any 12v output transformer) followed by a bridge rectifier will do all you want, it will NOT noticeably flicker, it does not require a smoothing capacitor as the human eye can't see any flicker above 25Hz approx,

The voltage out will be reasonably constant as you will not be varying the load. Use a couple of diodes or a resistor to fine trim the voltage down if required.

As long as you supply DC (smoothed or not) to the leds and do not exceed the rated current or temperature, you will not adversely effect life.

[musht]

Guess Tim as guy who designed electronics for most of Abstract`s effects has more things to do than push overpriced power supplies...

 

Back in the eighties there was all sorts of problems when L.V. lighting came in, lamp life measured in single number hours, an issue when an MR16 was 6.50 GBP.

 

Wound trafos underloaded go way out of regulation, a 12V nominal trafo can easily hit 16V way too much for a 12V lamp, one goes voltage rises , another one bites it.

 

Lesson, 12V isn`t always 12V

 

Rectifying an A.C. voltage gives an unsmoothed R.M.S. D.C voltage approximately 0.42 times higher than the A.C. that went in...

 

L.V. electronic trafos are typically 11.8V A.C. at over 20Khz , 11.8 to try and extend lamp life, not sure what difference to RMS voltage the frequency makes but reasonable guess rectifying it, it is more than 12V D.C.

 

LED strip generally uses simple resistor, any variation in voltage can make significant difference to current drawn.

 

Expensive PSUs? you need to change your shopping habits, apart from wee onelinked from Screwfix all sorts available nowadays, think meanwell.

[Tom Baldwin]

the human eye can't see any flicker above 25Hz approx,

 

Untrue.

 

It may not be very obvious if you look directly at the source without moving, but it's extremely apparent when the light source moves through your field of view.

 

Why do you think there's a market for 100Hz TVs, for professional LED fixtures with PWM dimming in the multi-hundred hertz range, or (in the days of CRT monitors) graphics cards that can do 85Hz+ refresh rates?