Both Servos Misbehaving

[sunfish]

After installing both AP servos I thought it would be advisable to do some operational tests - why didn't I do this before I installed them????

When I switched the system on prior to doing a network configuration, one servo went hard over and proceeded to try and beat itself to death. The other did nothing. I have confirmed that both servos are getting Twelve volts.

Neither servo is detected by the network using my installed cable or by a Skyview manufactured one and when I connect the roll servo ( the beating one) I get a yellow network connection pins 1 and 6 message, but when I check the pins they are the right way round.

What gives? One dead servo and one psychopathic one? It's going to take hours to get these things out!

I have updated the system to V15.2 in case there was some network compatibility problem but it makes no difference. EMS, Knob panel andA/P panel detected flawlessly.

 

[Dynon]

Probably best to give our support team a call on this one - either 425-402-0433 or support at dynonavionics dot com - so we can work through this with you. The servos should not move, period, until they're recognized and configured in a system.

 

[sunfish]

I've now taken the servos out. On the bench, one is completely unresponsive, the other one has its arm going around in circles, tops, goes back and dances around some more. Sounds like they are going back to the Agent tomorrow.

 

[sunfish]

Thank you Dynon. The Skyview won't recognise either servo using a manufactured cable. I'll talk to Horsham Aviation tomorrow. I think you might want to look at them.

 

[Dynon]

On the bench, they shouldn't do anything at all. They need to be actively commanded by a Dynon EFIS to do anything. How are they being powered on the bench? What other wires are connected?

 

[sunfish]

I'm sorry, I should have made myself clear; the aircraft hasn't flown yet and the Skyview system is not installed except for the ADHRS.

By "bench test" I meant connecting the SV to each servo in turn with the network cable (and of course the ADHRS and GPS) and supplying twelve volts to the Skyview and servo power wires.

Skyview boots up just fine and appears to be working correctly. It shows terrain, position and detects when I slightly move the fuselage. I use a Dynon network expander (?) to connect the ADHRS and daisy chained the EMS, knob panel and A/P panel. The EMS page shows on the display and the knob panel works. I loaded ver. 15 in case there was a problem with the earlier version(13).

SKyview detected everything fine except the servos. I tried them both singularly and together. I tried with and without the daisy chained stuff. I was using a Dynon made network cable and changed cables. I checked and rechecked the network pinouts on the servos - they are correct, I think.

One servo, when connected, runs its stepper and the arm does some sort of uncommanded dance. When I hit network configure detect I get a yellow configuration message "error data1 pins 1 and 6" and no detect. I cannot find a pinout error in my wiring of pins 1 and 6. When I connect the other servo SKyview and hit configure detect it does not detect it. Everything else is detected just fine.

I had an incident Two years ago when I accidently reversed polarity during a bench test the system stopped working and I sent the SV, ADHRS back to  Dynon with an RMA and it came back as "No fault detected" but I don't think we sent the servos which I now think I may have damaged.

P.S. I think the oval HSI looks weird too 

 

[Raymo]

The servos cannot be connected to the network using a standard network cable; they must be wired specifically per the install manual.

 

[sunfish]

Hi Ray, what am I missing here? They are wired exactly as per the install manual using the supplied DB9 connector and the Dynon servo installation kit , which is just a big network cable with power wires (red and black) and the yellow AP disconnect line added. I really hope I have messed up the wiring, it will save some postage  :-?

 

[jakej]

Sunfish

You have a pm

 

[vlittle]

What vintage are the servos? Dynon had an issue about 3-4 years ago with the servos not communicating with the SV.

Vern

 

[Raymo]

Hi Ray, what am I missing here? They are wired exactly as per the install manual using the supplied DB9 connector and the Dynon servo installation kit , which is just a big network cable with power wires (red and black) and the yellow AP disconnect line added. I really hope I have messed up the wiring, it will save some postage  :-?

My response was referencing your mention that you had them connected using the standard network cables. It sounds from this response that you have them wired correctly using the harness Dynon sells for the servos, which means you had to terminate one or both ends with the DB9 connectors per the install manual.

If you go back a rev or two in the manual, you'll see that Dynon used to recommend wiring the red, black and yellow wires outside the DB9 on the servo end. I think this was done to avoid the accidental use of a standard network cable. The most recent revision I have (Y) has the wires all within the DB9 with the following warning:

Extreme care should be observed that D9M connector for the servo CAN ONLY BE CONNECTED TO THE MATING D9F CONNECTOR FOR THE SERVO. If either of these servo DB9 connectors is connected directly to a SkyView Network connection, the SkyView displays (which supply power to the SkyView Network) and other SkyView Network components can be damaged and require non-warranty repair.

Apologies if I misunderstood previously.