Dynon Dimmer Configuration with Avidyne IFD 540

[362PC]

Last week the avionics guy finally got the dimmer working. It is the Dynon factory dimmer rheostat and has been connected to both the Skyview HDX network, the IFD 540 and the AMX 240. When the rheostat is turned full off the Avidyne products go full bright, but the Dynon is not full bright. Playing around with the settings I was not able to get a zero setting on the rheostat to make the HDX screens go full bright, they were always less.

Turning the rheostat to full power made the screens full bright, but then the Avidyne products were less than full bright.

I have the Brightness Source set to External
100% Brightness Voltage - 12v
75% Brightness Voltage -10v
50% Brightness Voltage - 9v
25% Brightness Voltage - 6v

Minimum Brightness Voltage - 12v

Does the zero setting on the rheostat default back to using the ambient light sensor? or is there another trick to getting it to go full bright when off?

Any recommendations would be helpful.

 

[Rhino]

I assume you're referring to the SV-KNOB-DIMMER. From looking briefly at the documentation, it appears Avidyne may look at the dimmer control differently from Dynon. Dynon uses it to control brightness, so the HDX is brightest at the full clockwise position. The Avidyne documentation refers to the adjustment as a dimmer control, so presumably it would be dimmest at the full clockwise position. The AMX240 manual specifically states that. The IFD540 manual is less clear, but does refer to it as a dimmer control, so I'm guessing it operates the same as the AMX240. If true, that would explain why the Avidyne boxes get brighter while the HDX gets dimmer, and vice versa. But that assumes I'm interpreting the Avidyne manuals correctly. I haven't delved that deeply into them, and I have no direct experience with Avidyne. There are also several dimBus settings in the 540 that must be configured correctly. I'd start by verifying those first.

If your BRIGHTNESS SOURCE is set to EXTERTNAL, it does not revert back to the ambient sensor on the HDX. It's one or the other. On the HDX, EXTERNAL BRIGHTNESS VOLTAGE should be set to 12 volts, and I believe MINIMUM BRIGHTNESS VOLTAGE should be set to 0 volts. But you can adjust MINIMUM BRIGHTNESS VOLTAGE to tinker with the results if you want. It's basically the equivalent of 0% Brightness Voltage.

 

[n144sh]

The IFD dimmer setup is / can be quite complicated. Suggest this as a starting point: https://pilotsupport.avidyne.com/kb/article/99-ifd-dimming-setup-tutorial/

 

[362PC]

Changing the IFD to the proportional curve has made the dimming work together better with the HDX. The AMX240 audio panel has no way to adjust change it to a true proportional curve and will always go full bright if dimmer is set to zero. All in all, much better with the proportional curve and not setting it to zero at night is a simple adjustment.