Question about wiring the WH-P30-1 trim wire on the AV-6000 side

[ymc9]

Hello guys,

I have the Garmin VFR package with autopilot, and I'm currently working on wiring the main harness. I'm a bit confused about the correct way to populate the WH-P30-1 d-sub pins on the AV-6000 side. The KAI mentions that with AP, the white and black wires should go to pin 9 & 6.



The 9-pin connector that comes with the main wire harness already has a pair of white/white-black wires populated on pin 1&2.



Reading the electrical diagram, these two wires are to be connected to AP servo's "TRIM IN" ports:



I'm not exactly sure what Vans meant with the "WITHOUT AUTOPILOT" annotation on the KAI. Am I supposed to remove the original pin 1&2 (given that I have AP), or do they still serve a purpose even with AP installed?

Thanks!

 

[CTCole]

Yes, they still run the trim servo, so leave the white wire and the white/black stripe wire in place. Add the wires and pins for 5, 7, and 8. Check the continuity and you're good to go.

 

[Tony Kirk]

With an autopilot you must put the white & black wires from the trim servo WH-P30-1 in pins 6 & 9.

 

[ymc9]

This is what I found Garmin:

The GSA 28 provides an interface between the pilot's electric trim switch and a 3rd party 14 VDC trim motor. The stick switch is connected to Trim In 1 and Trim In 2 on the GSA 28. When the switch is active in one direction or the other, one input is connected to 12 volts, and the other to ground and vice versa, allowing for the operation of the trim motor in either direction. When the GSA 28 autopilot servo is powered, the output to the trim motor is generated by the GSA 28 itself using Pulse Width Modulation (PWM) with optional speed scheduling to run the trim slower as airspeed increases for finer control of the trim tab. If the GSA 28 loses power for any reason, the GSA 28 trim inputs are tied directly to the GSA 28 trim outputs through a normally closed bypass relay, and the pilot's switch controls the trim motor directly.

It sounds like the two TRIM IN pins on AP servos should be connected.

I’ll give Vans a call to confirm.

 

[N8DAV8R]

This is what I found Garmin:


It sounds like the two TRIM IN pins on AP servos should be connected.

I’ll give Vans a call to confirm.

I think you may be conflating the two sets of white:white/black wires. The white/black set coming from the pitch servo to the power module are different wires than the white/black set from the trim servo. The set you have there in the connector are appropriately in pins 1&2.

Like Tony said, the pair that is in the WH-P30 needs to be on pins 6&9.

 

[ymc9]

I think you may be conflating the two sets of white:white/black wires. The white/black set coming from the pitch servo to the power module are different wires than the white/black set from the trim servo. The set you have there in the connector are appropriately in pins 1&2.

Like Tony said, the pair that is in the WH-P30 needs to be on pins 6&9.

Hi Nate,

Thanks, I'm aware there are two sets of white/white-black wires. What confused me was whether Vans "implies" in the following diagram that pin 1&2 should be EMPTY on the d-sub when AP is installed. Now I think it's a false interpretation from me, and the existing wires on pin 1&2 should be kept as you said.

 

[Tony Kirk]

Thanks Nate, I'm wrong again. I edited my previous post. Jeez, my name is on the WH drawing and I still get the details wrong.

Pins 1&2 do go to the AP servo, the white & black wires from the trim servo WH-P30-1 go in pins 6 & 9.

 

[N8DAV8R]

Hi Nate,

Thanks, I'm aware there are two sets of white/white-black wires. What confused me was whether Vans "implies" in the following diagram that pin 1&2 should be EMPTY on the d-sub when AP is installed. Now I think it's a false interpretation from me, and the existing wires on pin 1&2 should be kept as you said.

View attachment 114549

They definitely could be more clear about it, just a few words that diagram would fix it. I think the wiring diagram for the DB9<->Power Module interface is the guide here and clears things up.

 

[N8DAV8R]

Thanks Nate, I'm wrong again. Doh!

Pins 1&2 do go to the AP servo, the white & black wires from the trim servo WH-P30-1 go in pins 6 & 9.

I have been fortunate enough to work on both Garmin and Dynon AP/Trim RV-12 systems and upgrades recently. Thanks to your help along the way I feel like I actually understand them a little bit!