Pilotlights dual dimmer

Is anyone using the Pilotlights dual dimmer https://www.pilotlights.net/pwm-dimmer-12-vdc-2-channel-design-high-power-7-amps-channel?

It is also sold by Spruce and there is a single channel version available.

I have the dual dimmer setup in a new panel to dim a strip light and also a G3X system. I am getting a bunch of flickering, the G3X doesn't dim down very much, the reaction to turning the pot is slow, and the strip light gets to about half dim and then just cuts off completely. Getting the same results on both channels.

I will contact them Monday and see if mine is just defective, but was wondering if anybody else had any issues with them.

A lot depend on teh stripe light. I bought some LED stripe lights from e**y. They work quite well with a $5 rheostat and variable voltage. Dim quite low. Just be sure to get one with a high enough wattage rating for your light strip. You can get a rheostat with the switch built in, as well. Get the stripe lights with the lower power leds. Those with the more powerfull LEDs are hard to dim low enough for cockpit lighting at night. I had also used the kick PWM dimmer and it didn't get any dimmer than with the rheostat. PWM runs the risk of generating noise. Rheostat is clean and noise free.

G3X should be dimmed with a small $2 rheostat/pot. Wattage is irrelevant for this one. They use a voltage sense for external dimmer control, so I would expect a pwm dimmer to be problematic for that application. PWM is not variable voltage, but the same voltage turned on and off at a variable frequency. Works well for resistive applications or LED's without built in resistors.

I have no experience with the product referenced, but do know that many have had problems in the past and the kick version and perihelion version were the least troublesome and noise free

See the PWM in the title? That means ?pulse width modulation?. It dims lights by rapidly turning off and on many times a second. The longer off, the dimmer it appears to your eyes, which can?t detect the rapid on-off. But the G3X ?dimmer? is just looking for a steady voltage, which it uses to control its own internal dimmer. Applying the rapid on-off signal will likely confuse it.
If you want to keep it, feed the signal thru a resistor, then a capacitor to ground, to smooth it out.

The advantage of PWM circuits is that they can control fairly large currents without wasting energy or generating a lot of heat. But the G3X pulls very little current. Same for LEDs. Just a simple pot should work fine here.

need a filter

I'm using these sucessfully in a few applications- controlling LED strips, seat heaters, and the G3x lighting bus.

For anything that needs a true analog level like the G3x, you need to filter the PWM output of the dimmers to create a real analog signal. A simple RC low pass filter did the job nicely for me. You could choose a lot of different RC values to do the job well. I don't recall what I used on mine, but experiment a little using online RC calculators. You want a fairly low frequency, fast enough that the lighting level doesn't change too slowly, slow enough to remove all the switching frequency components of the PWM.


-Greg

Use the GAD 27

Instead of adding this additional unit, suggest you use the GAD 27 lighting control. (You did include a GAD 27 in your G3X design, didn't you?) Per the G3X installation manual (page 3-2):

I'm using it on my RV-10 to control switch back lights, manual avionics lighting level, and overhead lights.

Cheers,

really?

For those using the VPX, spending $600 on a GAD27 seems pretty silly just for lighting control when a $2 pot would work ask well...

If that's all your using the GAD 27 for, I would agree. But I didn't install a VPX.

True

Had I not used the VPX, I would have the GAD27. I actually had it ordered and the avionics guys said it was mostly redundant so I opt to not install it...

It would have been nice to have another 10 discretes, though!

A_S 4-channel dimmer

I installed the 4-channel dimmer sold at aircraft spruce, about $70.

I connected the 4 dimmer switches to an overhead baggage area led strip, two over-the-shoulder flexible goose-neck map lights, the panel led lighted honeywell rocker switches, and to the dimmer circuitry for the G3X GDU 645 and 470 displays (still trying to figure out how to hold my tongue to get that to work).

The dimmers work fine through a wide range of dimming, no flickering. Haven't operated yet with the engine running.

ink to spec sheet:
https://www.aircraftspruce.com/catalog/elpages/4channeldimmer13-15799.php