Show Planes Flap Positioning system problem

[cleve_thompson]

I have the ShowPlanes FPS in my RV9A and like the system very much and have been flying for 170 hrs without problems. Lately, however, I have had 3 occasions when the circuit breaker on the flap motor popped when the flaps were positioned fully down. I would guess that this was due to the flap motor continuing to run after the full flap position was reached. This has occurred only in flight so I can't be sure it is due to the motor continuing to run.
What do I need to do to correct the problem. When I reset the breaker, the flaps extend (come up) normally.

[flybye]

Of the four potential causes, 1) Defective breaker, 2) Defective wiring 3) Drive system 4) Mode of operation, it would seem that the last should be investigated since the problem only occurs in flight. Possibly, wind resistance is increasing the load on the motor outside of the tolerance set by the breaker. Have you contacted the manufacturer of the FPS? Ask about reports of similar problems. You might want to try simulating the wind resistance scenario by pulling on the flap as it deploys. You could also measure the motor current while doing this test. I believe it should be in the range of 7.5A. Hopefully someone could provide a tolerance for this. What value is the breaker? Is it quick or slow blow?
Good luck, let us know your progress in diagnosing this.

[jjconstant]

Check that the rod end attached to the actuating arm has not slipped (jam nut/safety wire loose) and wound itself all the way IN. When I was doing my initial installation of the FPS I purposely screwed the rod end all the way in and it prevented the flap motor from clutching at that end of the travel (flaps fully extended). The positioning system was still supplying juice but the motor was stalled. The noise from the motor stopped but I saw smoke! Backing the rod out 1/2 turn allowed it to clutch.

Jeremy

[RetiredRacer]

I had installed the Show Planes flap position unit back when I built the 9a but didn't wire it in at the time. Over the weekend I had the seats out and was doing some work under the panel and decided to wire the flap position unit up while I was at it.

It works well with one small hiccup. And this could probably be solved with some adjusting. When it retracts it shuts off nicely when the plaps are fully retracted. But when it goes to full flaps it shuts off with about one degree of travel still remaining. This is no problem as I'm happy with that amount of flap out. But if you hit the switch again it will travel that one degree and then the motor hits the full extension clutch and keeps running.

I had to pack up at this point because of time, so I didn't have time to look to see what adjustments would solve this little problem.

Has anyone that have installed this unit and have had the same issue know what can be adjusted without changing the full up stop?

Thanks.

Bob

[aerhed]

I've seen this. I haven't done it yet, but I think if you file/dremel the end of the detent rod from the last notch to the end of the rod(about 3/16?) so that you have an endless notch it will stop the run-on.