Servos Offline

[swatson999]

There's also the Recent Flight Data Log datafile, which you can look up in the manual, that records the last 15 minutes at the max rate, so you don't have to set your standard data file higher (and thus decrease the amount of time that can be stored). You do have to remember to save the datafiles within 15 minutes of the event, though.

It's all in the manual.

 

[PaulSS]

I think I've written this before but, just in case.......

My autopilot worked perfectly for over a year and then I started to get warnings that my pitch servo was offline and it was.

I chased the electrics and discovered no snags. Deep in the depths of my addled memory I recalled someone mentioning transponders, so I turned mine off and, hey presto, pitch servo behaved itself.

I moved the transponder antenna further away from the pitch servo and have never had any problems with it since. Clearly I was getting some stray wigglies from around the transponder transmitting and this was upsetting the 1s and 0s going to my servo.

As I said, this was a good year into operating with no problems and I have no idea why it started to play up, as I had changed nothing. Maybe have a fly around and turn off your transponder. It's an easy test

 

[jakej]

I think I've written this before but, just in case.......

My autopilot worked perfectly for over a year and then I started to get warnings that my pitch servo was offline and it was.

I chased the electrics and discovered no snags. Deep in the depths of my addled memory I recalled someone mentioning transponders, so I turned mine off and, hey presto, pitch servo behaved itself.

I moved the transponder antenna further away from the pitch servo and have never had any problems with it since. Clearly I was getting some stray wigglies from around the transponder transmitting and this was upsetting the 1s and 0s going to my servo.

As I said, this was a good year into operating with no problems and I have no idea why it started to play up, as I had changed nothing. Maybe have a fly around and turn off your transponder. It's an easy test

Brilliant idea Paul - I don’t know why a few of us didn’t suggest that. Then again not knowing/seeing the install details is one of the difficulties around ‘online’ troubleshooting. . Those electron critters are just waiting to pounce .

 

[airguy]

Brilliant idea Paul - I don’t know why a few of us didn’t suggest that. Then again not knowing/seeing the install details is one of the difficulties around ‘online’ troubleshooting. . Those electron critters are just waiting to pounce .

It can be like herding cats, keeping them all in line where they belong.

 

[Rhino]

Yeah, those critters have gotten me sooooo many times.

 

[mikelupo]

I had a strange problem after adding my remote magnetometer. My servos would not go offline, but I could not engage the AP. I had to remove the yellow wire from the d-sub that goes into the magnetometer. Problem solved.
Some details about my install… I added a hub out in the wing so I would not have to run two long network cables as my conduit was full and could not accommodate the second network cable. That said, I route a network “trunk” from behind the panel, out in the wing through the conduit to a hub mounted on a rib. Then route from the hub to the servo and to the remote magnetometer out in the wingtip.

 

[jakej]

I had a strange problem after adding my remote magnetometer. My servos would not go offline, but I could not engage the AP. I had to remove the yellow wire from the d-sub that goes into the magnetometer. Problem solved.
Some details about my install… I added a hub out in the wing so I would not have to run two long network cables as my conduit was full and could not accommodate the second network cable. That said, I route a network “trunk” from behind the panel, out in the wing through the conduit to a hub mounted on a rib. Then route from the hub to the servo and to the remote magnetometer out in the wingtip.

The A/pilot CABLE IS DIFFERENT to the standard network cable for a reason. The network wires ie pins 1&6 + 4&8 are the network wires common to all the other network wires needed for the system to ‘see’ the other network items. Grounds (I allocate to pin 2) & power (pin 2) are 20 awg with ground going to a local point & power going to its own breaker/s. The Yellow ( pin 3 is my choice) goes to a/p disconnect switch & that’s it. Read the Manual - it has a diagram too.

 

[airguy]

The Yellow ( pin 3 is my choice) goes to a/p disconnect switch & that’s it. Read the Manual - it has a diagram too.

Ouch! RTFM has now gone to "look at the pretty pictures"

 

[mikelupo]

The A/pilot CABLE IS DIFFERENT to the standard network cable for a reason. The network wires ie pins 1&6 + 4&8 are the network wires common to all the other network wires needed for the system to ‘see’ the other network items. Grounds (I allocate to pin 2) & power (pin 2) are 20 awg with ground going to a local point & power going to its own breaker/s. The Yellow ( pin 3 is my choice) goes to a/p disconnect switch & that’s it. Read the Manual - it has a diagram too.

Yeah, I'm pretty sure my soup to nuts install would not have gone well had I not done both! LATPP and RTFM. Everyone is afforded a mistake here and there. Especially trying to digest a 500+ page install guide, with block diagrams, wiring diagrams, third party wiring diagrams, etc... that do not necessarily concur with each other. Anyway...I found mine and corrected it. I'll take the shade... It's hot here today.

 

[ZK-SVH]

Hi everyone.

Well I got to the hangar today and to my consternation found the aircraft close to electrically dead, despite being left with the master definitely off. Changed batteries etc, confirmed full charge. Multi meter showed only 3.5 volts or so at the master and at other points in the system.

Started looking around and quickly found the culprit. 12V from the battery goes to solenoid on the firewall with a ring terminal on a stud. Nut on the stud had vibrated loose so an intermittent contact, resulting in an occasional voltage drop/total cutout on the whole system. If this had been happening just fleetingly as I previously described then lights and radio would go back to work but obviously not the A/P, and even if the A/P wasn’t engaged the “Servo Offline” message would have been momentarily triggered. (I had noticed engine cranking just a tiny bit slower, I’d put that down to winter temps…)

I‘d previously thought of this as a possible scenario but hadn’t investigated it. (June 20 post) Another good example of me going straight to complicated scenarios rather than eliminating the basic. Anyway I’m really hoping I’ve put this gremlin to rest….. See what happens when I get to fly next.

Thanks to everyone for their input and especially JakeJ.

Peter

 

[ermed5]

Hi everyone

I have a Skyview HDX with autopilot, operational in my aircraft for about 190hrs and 18 months. I’ve really been enjoying it.

Recently though I’ve found that my servos are going offline. I get a aural “Message” warning, with the word “message” being momentarily displayed, but when going to the message there is no message there, except a couple of times I’ve been fast enough on the button to open the message “Pitch servo offline” together with “roll servo offline.”

At the same time flashing very briefly in the autopilot task bar I get the two white crosses indicating that the servos have gone offline. However it is always only momentary, literally the blink of an eye and I don’t always see it. The white crosses never remain as they do when I power the servos down by pulling the breaker.

If the AP is engaged it disconnects.

I’ve read every relevant thread I can find and looking at the user guide this message is supposed to indicate loss of power to the relevant servo. Power to my servos comes from a 5 amp breaker. From this breaker each servo is ”fed” with a separate wire. Likewise each servo has a separate earth. So I’m reasonably confident it’s not a continuity problem there. I’d initially suspected that it might be transponder interference I’d read about, but the data and power wires are down one side of the airframe and the antenna wires the other side.

The antenna is about 30 inches from the servos, and in any case it all worked flawlessly for quite some time, and flight testing with the Tx off I still intermittently have the scenario described above.

The two servos plug into a hub adjacent, with a network cable going forward.

Is there a possible failure mode in the breaker (Klixon) that results in a fleeting interruption of the power supply? (Will swap it out as soon as a replacement arrives.)

Something wrong with the network cable exiting the hub maybe but this hub also has remote magnetometer plugged in and I’ve never had an indication of a problem there.

Is it possibly a software thing?

Any thoughts greatly appreciated.

Thanks

Peter

I had this same issue last year. Everyone here was so helpful. I just could not find the source of this power loss. I even sent both servos back to Dynon, where they were run for a few days, and returned to me in normal working condition. The HDX menus did not find either servo (like they were never installed). I even had a VERY skilled avionics guy take a look, and we could not find the power loss source. I think someone here made this suggestion... run a new power line from each servo directly to another power source... and voila! Both worked (i was already depressed that I'd have to remove the interior/floor and retrace each damned wire). So, started fiddling behind the C/B panel... nothing. Changed out the Klixon C/B to a new one... nothing. Then redid the ring terminals and attached them to another source (different C/B) on the bus. And bingo... they worked! Either the old ring terminals or something in/around that C/B was/were goofy.

Try the 'jerry rig' with separate wiring. What a struggle this was. Working perfectly since.

 

[airguy]

I had this same issue last year. Everyone here was so helpful. I just could not find the source of this power loss. I even sent both servos back to Dynon, where they were run for a few days, and returned to me in normal working condition. The HDX menus did not find either servo (like they were never installed). I even had a VERY skilled avionics guy take a look, and we could not find the power loss source. I think someone here made this suggestion... run a new power line from each servo directly to another power source... and voila! Both worked (i was already depressed that I'd have to remove the interior/floor and retrace each damned wire). So, started fiddling behind the C/B panel... nothing. Changed out the Klixon C/B to a new one... nothing. Then redid the ring terminals and attached them to another source (different C/B) on the bus. And bingo... they worked! Either the old ring terminals or something in/around that C/B was/were goofy.

Try the 'jerry rig' with separate wiring. What a struggle this was. Working perfectly since.

Intermittent electrical issues will give you gray hair and cirrhosis of the liver.

 

[Rhino]

Intermittent electrical issues will give you gray hair and cirrhosis of the liver.

Also male pattern baldness and erectile dysfunction.