DIY LED Lighting for stairs

I designed and installed LED lighting on all the stairs in the house. It's inexpensive and maintenance free. They run 24 hours a day and electricity cost is less than $2 per month for about 40 stair treads.

Total installed cost was less than $90.
Materials, 400 LEDs, 6 diodes, 6 capacitors, 100 feet of telephone wire, 200 feet of 3/8 inch OD clear plastic tubing. about 20 min. labor per stair.

Its been operating for 2 years so far with no problems. Based on Mean time to fail data for the components it should last 10 years. I never have to turn on lights at night to use the stairs and the occupants in the theater can exit without breaking their necks.

Appearance is beautiful and dramatic. I recommend this to everyone with stairs in their home.

two photos were taken of the stairs at the theater entrance. One shows the lights on the central stair.

Different techniques were used on each stair. In the theater, the LEDs are encapsulated in the plastic tube and placed along the inside lower edge of the step. The central stair has the LEDs placed under the lip of the tread at the top of the riser.

I have additional photos of a spiral stair and a single step that I'll post of interested.

The circular stair.

The LEDs were located under the tread on the inside corner only. This location lights the tread immediatly below it while creating a gradient across the surface. I found the gradient across the tread is very effective and helps choose where you will step. Also fewer LEDs are better.

I also found lower intensity is better. If the LEDs are too bright, your night vision is compromised. So less is better.

This is a step down from one room to another. The LED string is under the top tread and uniformally lights the lower surface. This highlights the area below and sets a strong contrast with the end of the step making it easy for the person entering/exiting the room to see the coming step.

Three photos attached
first: Components, LED's, Capacitor's, telephone wire and Plastic tubing (missing diode, could not find one laying around.

The LED's are standard 2mm diameter PC board type. (note one lead is longer than the other-important cuz that designates polarity). Color-I prefer yellow or orange. I tried red, green, yellow and orange. The red and green are interesting but yellow and orange are easier on the eye. IMO.

Diodes are wired in series with the capacitor and the diode. About 25 LED's can be strung across one stair. Each diode drops about 3v it when lit up. Total drop across this string will be about 75v. The capacitor will current limit the string to 2.2ma peak. The LEDS will operate on a 35% Duity cycle (the diode blocks the negative half cycle and the LED's wont turn on until their forward voltage is exceeded).

Power per stair tred will be about 120mw. ( ~0.1watt per stair tred. For 13 step stair thats ~1.3 watts. For one month thats about 1KWHr or 25 cents per month at $0.25/KWHr)

The eye responds to peak light intensity so even though the LED's average very low current and low duity cycle. We percieve it as quite bright.

The capacitor I use is .1 micro farad. That sets the peak current to 2.2ma. That is about one tenth the current necessary to cause muscle clamp on if you should accidently get hold of the wires while its on. You would feel a tingle but nothing remotely close to life threatening. Quite safe for children and dogs.
(NEVER, NEVER, NEVER use electrolytic capacitors. They will blow up when reverse biased like a shot gun.)

I use 2mm LEDs they are small enough to slide inside the plastic tube and large enough for fumble fingers to handle. The also have standard leads greater than 1 inch. I take advantage of that by folding the long lead back over the diode and soldering it to the next diode in the string. That sets the spacing of the diodes and eliminates extra wiring between LED's.

One string consists of 25 diodes and one capacitor at one end. A wire is soldered to each end of the string. The string is inserted into the plastic tube and the ends sealed with silicon glue.

Each tread has the plastic tube mounted below the tread at the top of the riser. The marble stairs had a gap that i was able to shove the tube into with no additional mounting effort.

The wood stairs required a molding from Orchard Hardware to hold the tube and act as a light baffle. The molding is normally used to trim 1/4inch wall paneling. Its perfect, the rounded front section is where I bonded the plastic tube. The molding was glued directly to the bottom of the tread. I even painted the front of the trim baffling to blend with the riser color.

More to come if u want it.

The ratty looking scrap of 2 x 4 in the back ground has slots cut in it to accept the formed diodes. I just drop them in the slots and can quickly solder the lead ends together. Saved a lot of fumble finger work.

Correction to previous post. The LED's are 3mm not 2mm. I purchased them 4 years ago (1,000 LED's for $50). That supplier does not offer that package today. I found a different supplier today with comperable prices.

http://www.westfloridacomponents.com/03mmLEDs.html

The diode I would recommend is a 1N4003 the above supplier sells it for $0.10.

The spiral stairs were the first stairs I wired up. The circuit was slightly different. I used an old wall wart left over from one of the kids toys to provide the power source. It was a 9v 300ma type. This was plugged in to a convenient outlet and the telephone wire was connected to the leads from the wart. Each stair was wired with 2 LEDS and one resister in series. The resister value is 570 ohms 1/8 watt. This limits current to 5ma for the LED's. Each stair tread light set is wired in parallel to the telephone wire that ran up the stair under the moulding.

The use of the wall wart has advantages and serious limitations. Because of the low voltage output, electrocution is a non issue. However, the LED's must be wired in a combo series/parallel fashion. This complicates the wiring. Also, the wart is visable instead of hidden inside the outlet and the wart is inneficient dissapating power of its own.