Speeddog8
Member
- Joined
- Mar 30, 2010
- Messages
- 64
My Glasair has a larger linear actuator trim motor, so I decided it necessary to install a TrimAmp device. During my avionics upgrade a few months back to all HDX equipment, the TrimAmp wasn’t available, so I had to improvise with a TCW Technologies unit in the meantime. I’ve finally got round to swapping out the TCW unit for the TrimAmp. Once installed, I went to trim motor configuration and selected that a Trim Amp had been installed. Problem is, when tested, it acts as if the TrimAmp isn’t putting out sufficient power to move the trim motor AT ALL. The trim motor makes a bit of noise (buzzing) and the green light on the TrimAmp switches to yellow when I select up or down trim, but no movement of the trim motor. I’ve confirmed the wiring/pin-out and I’ve done some extensive troubleshooting. Everything seems to point to a faulty TrimAmp unless someone has a remedy here. Troubleshooting: I’ve bypassed the aircraft’s ground and power to the TrimAmp (straight to a hot battery, inches away) but no change. It performs exactly the same. I’ve checked the output from pins 11 & 12 from the TrimAmp to the trim motor which initially shoots up to 12 something volts and then quickly declines to 11.87 volts. Polarity changes with switch position as well. Odd, but 11.87 volts still ought to run the trim motor. Suspecting that my trim motor might have died during the install, I ran the motor up and down jumping the D-sub pins 11 & 12 removed from the harness to the same battery previously mentioned.. Using the aircraft’s wiring, I’ve checked the voltage coming from the TrimAmp back to the AP Panel on pins 9 & 2 (12.27 volts / ship battery). My AP Panel is also wired via pins 14 & 15 to a Ray Allen servo in the aileron (Motor 2). It works fine as always. I’m running out of ideas? Anybody run into this issue before?
