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Ray Allen POS-12 Flap Position Troubleshooting

Bart

Well Known Member
I seem to be having a problem getting the flap position (indicator) to display properly using a VPX and G3X. Flap motor works fine. All of the trim servos work fine. I have rechecked every Tosten wire on the stick to make sure there is no loose ground or mal-placed wire. Using the VPX configurator the position does not change smoothly and near the top I momentarily peg out roll and elevator trim indicators on the PFD. Mechanically everything seems to work well just getting the indicator to display on the G3X properly or at least closley represent what's happening when the flaps are moving is my challenge....anyone else have this issue. Appreciate any thoughts if you've seen this before.
 
Bart,

Have you deactivated the serial port on the G3X for the flaps? If you haven't, you will need to go into the config mode and go to the serial port that you have selected for your flaps on the flaps configuration page and make sure it's turned off. That will allow the VP-X to control the port.

Same for your trims. Make sure the selected serial ports are turned off.
 
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I ended up not using the POS-12 but I can think of a couple of tests. First, hook up your computer to the VP-X and see what indications it is showing through the full range of motion. Second, unhook the wiring on the position sensor and hook up a multimeter between the center wire and one end and run it up and down, see if it’s smooth. I would check both end wires, actually, just to be sure there isn’t any weird bouncing going on.
 
Pat, Yes! In fact it was deactivated - I reactivated it - then deactivated just to look for signs of change.

iamtheari - Checking the voltage shows the first inch of travel begins normally then freezes until nearly at the end...then boom full voltage....and this is what is shown on the display. Pretty much the same on all the wires. SO with that idea I guess the display may actually being showing correctly. However its my understanding these POS 12's are nearly bullet proof so I don't want to believe its the brand new out of the box sensor yet.
 
My elevator trim did this until I improved the connector at the servo for a more reliable connection.
 
Bart,

Have you deactivated the serial port on the G3X for the flaps? If you haven't, you will need to go into the config mode and go to the serial port that you have selected for your flaps on the flaps configuration page and make sure it's turned off. That will allow the VP-X to control the port.

Same for your trims. Make sure the selected serial ports are turned off.
Can someone describe exactly what settings are being referred to here? I don't know of a serial port for flaps or trim on the G3X.

I am seeing a similar situation as the OP describes, except that I have Pat's wonderful flap actuator in my plane instead of the stock unit. Basically, the VP-X software reports a position of about 220 for half flaps and about 225 for full flaps. Position numbers go up pretty smoothly from retracted to halfway.

I don't know what the G3X could be doing to interfere with the VP-X's measurements, but if there's any chance a configuration option will help I want to find it.
 
Based on my going back through all of my wiring, settings, and phone calls to each vendor in the loop...VPX, Stick, and Garmin, as well as rechecked all pinned connections to servos - I have asked Ray Allen to send me another unit. I think mine is related to the unit as the multimeter appears to be doing exactly what the display is showing. It is possible I over-pulled the slider on the first test. The unit slider feels OK but the sporadic signals are just too coincidental to the movement of the slider. Not sure if that makes sense not....I hope to get the new unit before the weekend. I'll provide an update when I can swap the POS-12.
 
Bart,
I have the VPX-pro and G3X on my -14A. While Van's flap position indicator works well on the G3X, the elevator and aileron trim position indicators do not. In the VPX-pro configurator scale (0 - 255), neither the elevator or aileron trim positions are linear, similar to your readings. Did changing the Ray Allen servo solve this problem for you?
 
Pos

The POS has a linear movement. Most connect it to the rotary output of the torque tube which will flex the POS if rigidly mounted. Also, the POS doesn’t work well near its endpoints. Can you get it to work? After some futzing with it yes. There is a better option…

Do yourself a favor and install the PH Aviation actuator; it has built in position sensing.
 
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