Dimmers, Nulite's and LED light strips.

terry.mortimore · #1 10-29-2012, 11:41 AM

Hi gang:

I'm working on my Panel lighting and I had planned to use a LED light strip under the glare shield (Stein's unit). I have Dynon D-100 and D-120 glass, I also have three 2 1/4" back up instruments with Nu-lites to light them.

I'm wondering if one Dimmer switch will control everything at the appropriate light levels, or will I need two Dimmer controls?

Any experience out there? I'd appreciate any input.

Also wondering which Dimmer control to buy.

Thanks, Terry.

Beancounter · #2 10-29-2012, 12:02 PM

Terry
I used the Kick PWM dimmer (KR6?) to drive my LED strip lights. Unfortunately I bought the brightest (at the time) LED's. So even dimmed to the lowest setting it is too bright for night flying. I now have covered them with electrical tape. I tried using the same dimmer for the compas but it was incandescent and needed more juice than the LED's. My 2 cents, buy low intensity LED's with a low # of diodes per foot.

ccrawford · #3 10-29-2012, 12:07 PM

I don't think you can use the same dimmer for both, nor do I think you'd want to. I have nulites for my backup instruments but decided not to install them for now, as my over panel LED strip seems bright enough to light them up (on the bottom edge of the panel no less).

If I install the nulites I will use a different dimmer switch which connects to the powerpack for the nulites.

PaulR · #4 10-29-2012, 12:11 PM

I used Steins LED strip as well. I also have two back up 2-1/4" instruments. There is PLENTY of light from the led strip for them. I used Van's dimmer, though I can't remember the part number right now.

A little note on the Dynon's. Be sure to set the auto dimming to "on" before your first nite flight!!!

RV6_flyer · #5 10-29-2012, 12:44 PM

LEDs need to be pulse width modulated for dimming.

See Flight Data Systems for a dimmer that will work with both LEDs and regular lights.

Tell Chuck Newman that I said hello and sent you if you buy anything.

BobTurner · #6 10-29-2012, 01:00 PM

"LEDs need to be pulse width modulated for dimming. "

Sometimes yes, sometimes no.
For real power applications (like landing lights) you don't want to be wasting huge amounts of power into a series resistor, so yes these applications use their own current regulator to avoid burning out the LED and they will not dim properly with a simple voltage regulator.

However, low power applications (like Stein's LED strip) just use a series resistor(s) to limit current, and they can be dimmed just fine with a simple varying voltage.

As to the original question: It is often hard to get different lights to the same desired level if they are all controlled by the same circuit. e.g., one will be too bright while the other is too dim. OTOH you don't want 10 different knobs for dimming. So make a reasonable compromise.

Finally, I built my own dimmers (2) for $5 from commonly available parts (an IC, a resistor, and a potentiometer for each). (I'm just driving low current devices with these.)

rzbill · #7 10-29-2012, 04:39 PM

I used 2 circuits.

One for the Nulites and one for a pair of LED floods (y'know those eyeball mounted ones) that illuminate the lower part of my panel where the switches are.

I bought a couple of potentiometers and LM317T voltage regulators from Radio Shaft. A few leads, joints and shoe goo (to afix the 317 to the pot body) and viola', adjustable lights. No discernable noise, even without the usual capacitors.

The rest of the avionics I left on their own internal photoeye control.

terry.mortimore · #8 10-30-2012, 07:30 AM

Thanks for the input guys, looks like I'll have two knobs on the panel.

Aircraft Spruce list a nice looking dual unit, I'll probably go that route.

http://www.aircraftspruce.ca/catalog...channelpwm.php

cheers, Terry.

mrreddick · #9 10-30-2012, 05:35 PM

Quote:

Originally Posted by ccrawford

If I install the nulites I will use a different dimmer switch which connects to the powerpack for the nulites.

I have a 10 year old custom panel from Aerotronics and a few months ago my Nu-Lites went dark! You mentioned a power pack for them. If I have a hidden power pack, how big is it?

rocketbob · #10 10-30-2012, 05:43 PM

Quote:

Originally Posted by terry.mortimore

Thanks for the input guys, looks like I'll have two knobs on the panel.

Aircraft Spruce list a nice looking dual unit, I'll probably go that route.

http://www.aircraftspruce.ca/catalog...channelpwm.php

cheers, Terry.

Man I need to design some dimmers. That thing is literally $3.00 worth of parts.