GFC 500 and IFD 440/540

[mike_elliott]

12 minutes ago, Barry LeBlanc said:

Hi Mike,  You can put away that harness of yours when you upgrade to a 3100AP. The 3100 AP runs the servos for 5 seconds in each direction once powered up. This will clean the servos motors. We have over 140 thousand of these units in the field today. I welcome you to tour the factory when you are in the Mineral Wells area and see our repair section. We have 1 person working on servos. From Polar to Polar these servos have a proven history. 

The 3100 uses a Pulse Width Modulated (PWM) signal to drive the servo motors rather than a ramped voltage signal used with previous S-TEC autopilot systems.  This allows the servo always receive maximum voltage and avoids high startup voltage problems.  The speed is controlled more accurately by the frequency of the PWM signal.  With over 140,000 servos in the field this allows customers to upgrade existing S-TEC autopilot systems without swapping out expensive servo motors

Nice! A welcome technology change

 

[Marauder]

Hi Mike,  You can put away that harness of yours when you upgrade to a 3100AP. The 3100 AP runs the servos for 5 seconds in each direction once powered up. This will clean the servos motors. We have over 140 thousand of these units in the field today. I welcome you to tour the factory when you are in the Mineral Wells area and see our repair section. We have 1 person working on servos. From Polar to Polar these servos have a proven history. 
The 3100 uses a Pulse Width Modulated (PWM) signal to drive the servo motors rather than a ramped voltage signal used with previous S-TEC autopilot systems.  This allows the servo always receive maximum voltage and avoids high startup voltage problems.  The speed is controlled more accurately by the frequency of the PWM signal.  With over 140,000 servos in the field this allows customers to upgrade existing S-TEC autopilot systems without swapping out expensive servo motors

Barry - if you purchase a new 3100, what servos are provided with it? Same as my 60-2 or are they different? If so, how?


Sent from my iPhone using Tapatalk Pro

[MIm20c]

On 8/5/2018 at 8:23 AM, mike_elliott said:

The servos have been a weak link in the STEC 20, 30 40's requiring frequent "cleaning" of the armatures to keep roll and pitch oscillations from occurring. Barry, will the 3100 magically fix this known issue? (I have a harness I made up to do this cleaning, simply running the servo motor in ea direction for a couple of minutes every 6 months or so)

I’m interested in this type of harness. Any links to buy / tutorials on usage. Mine has a slight pitch oscillation and I thought it was par for the course with this unit...

[mike_elliott]

1 hour ago, MIm20c said:

I’m interested in this type of harness. Any links to buy / tutorials on usage. Mine has a slight pitch oscillation and I thought it was par for the course with this unit...

I *think* it is pins 2,3,4, & 7 from memory, where 7 is ground, 2 is +, 3 is - and 4 is clutch. @Barry LeBlanc can confirm the exact pinouts and assignments of the sub min. D connector. Good thing is it wont hurt anything to hook up an old ELT battery to any 2 of the pins. You can also verify this by looking at the male connector and seeing what pins are used.

Running the pitch servo motor in both directions (pins 2 and 7 for a minute , then pins 3 and 7 for a minute) usually fixes this issue. 

DISCLAIMER

I AM NOT SURE OF THE PINOUT ASSIGNMENTS AND WONT BE UNTIL I CAN GET TO THE HANGAR I KEEP MY TOOLS AT.  good news, it wont hurt anything if you put a battery on any one of them. It will either 1) engage the clutch, 2) run the servo motor 3) do nothing.

meanwhile, I believe I have downloaded the stec install manual some time back if you want to wade thru it.