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Vertical Power Question: trims settings

Stockmanreef

Well Known Member
I am trying to figure out setting up the vertical trim and flaps through the VPX-Pro for my 14a.

Trim question: The position sensor range is 0-255--in theory. When I run the trim, full down is position 3, neutral is about 220-225, then I run out of positioning settings. In other words, I anything above neutral trim does not result in any change in when I move to full up. Up meaning, the trim tab is up and down the trim tab is down.

Flaps question: The VPX pro is inverse the switches. Thus when I tell the VPX pro to go "down" the flaps goes down using the VPX, but with the cockpit switches the flaps go up. If I invert the polarity, then it is reversed and the swtiches and VPX pro are still reversed. Is it easier to change all the switches or the motor wiring?

Ailerons: Work perfectly fine. Full scale swing for positioning in VPX pro and motor and switches are correct.

Thanks
ken
 
for the trim, is this just a bad potentiometer in the motor? The motor does allow the trim tab to run all the way up and down.

I know that Van's did send a different linker (from the motor to the trim tab), but I forget if the new one was longer or shorter.
 
Ken,
I have the VPX and the G3X and have 120 hours on it. I have not been able to make it work like I would like. I just did a measurement and elevator trim goes up 28 degrees and down 25 degrees. I cant imaging ever needing more than 5 degrees either way. If I was at 25 degrees, I would be doing loops.

I still look back to physically check my trim before each flight. The screen shows no movement then all at once. I would love to limit the travel and I think that will make the display work better.

We should get together and see if we can figure it out. If not, maybe head over to Lapeer to talk to the panel builders there. I would love to get this figured out.
 
I have VPX and my flaps work correctly. 3 position 10, 25, 40. I followed the setup in the MANUAL 5 years ago. Have worked fine since.
 
I just completed the Vans SB on my RV-12. The previous Ray-Allen servo worked perfectly with the VPX and Garmin G3X. But someone did something to the servo on their RV-12 so Vans sent out an SB ( nothing new here). I replaced the Ray-Allen servo with the new and preferred B6-7T. The first one RA sent had a bad 5K ohm potentiometer (very unusual) but RA sent me a new one which read the proper 5K ohms end to end. But like you, I still have this "Jumpy" sort of movement or no movement and then it jumps to the new position. I called VPX but the tech support person didn't know any more than I, (Chad would probably know). I'm going to call Garmin tomorrow and see if there's a setting somewhere on the G3X that can help me with the offset that you mentioned, I have the same offset.
 
Ken-

If you run the RA trim motor from end to end, it will go from 0-255. If it does not, then there is something wrong with either the trim motor/position sensor unit or the physical installation.

Perhaps disconnect the linkage rod from the trim motor, and see if it runs through its entire length (just over an inch) and goes from 0-255.

Regarding the flaps, they WILL work perfectly. It sounds like you have either the wiring or the settings backward. Try ringing out the flap switch input pin to make sure the correct pin is active low when you press the flap switch. If the flaps are moving correctly when controlled from the EFIS (or configurator), then the flap motor polarity is correct.
 
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