Pitch servo not seen

[swatson999]

On startup today, I got a pitch servo error...it actually came up as a Warning message the first time. Checked the network status, no Pitch servo seen. Had the system re-configure, and it still wasn't there. Power cycled, and it was. Later in flight, no pitch servo...again, rediscovery and it was there and stayed there. After landing, power cycled, pitch servo was seen, and all appeared normal. I'll check it again tomorrow, but this is the first time I've seen this sort of error.

I'm not suspecting a bad connection, as it's been rock-solid until now (and the pins were crimped with a *very* good crimper, pull-tested, etc.). Not sure what's going on here...ideas?

TIA!

Steve

 

[jakej]

Steve

I agree - most likely somethings up with a connection

Jake J

 

[swatson999]

Worked perfectly today...

 

[dabear]

I would say you have a wiring problem either with data or power.

 

[eddies]

Strangely enough I had the same issues before I upgraded to V5.1, since then all has been OK.

Before the upgrade on some occasions I had to do a forced discovery, other times just rediscovering of the network was fine.

For the comments that say wiring issue how would rediscovering the network cause a wiring issue to go away?

Regards,
Eddie

 

[swatson999]

Strangely enough I had the same issues before I upgraded to V5.1, since then all has been OK.

Before the upgrade on some occasions I had to do a forced discovery, other times just rediscovering of the network was fine.

For the comments that say wiring issue how would rediscovering the network cause a wiring issue to go away?

Regards,
Eddie

I'd like to know, as well...I'm not convinced it's a wiring issue. The harness was provided by Stein (not sure if they made it or Dynon), and is the standard one for both pitch and roll servos, only requiring inserting pins into the D-sub connectors.

It's worked fine now on two subsequent flights without any problems...I'm loath to pull out the interior and all the necessary panels to get to the pitch servo connectors just yet...

 

[jakej]

Steve

No reflection on you at all, so please don't take offence however surely you've seen other posts about pins not inserted fully ? I've had that happen too - there are some dsub connectors that require use of insert tool & others don't, just saying......

I've found (rarely) some issues with the supplied harnesses ( no one's perfect) too, I don't think Dynon make them but could be wrong on that

 

[swatson999]

Steve

No reflection on you at all, so please don't take offence however surely you've seen other posts about pins not inserted fully ?  I've had that happen too - there are some dsub connectors that require use of insert tool & others don't,  just saying......

I've found (rarely) some issues with the supplied harnesses ( no one's perfect) too, I don't think Dynon make them but could be wrong on that 

I'm not taking any offense, and heaven knows, I've made assumptions about error sources before that have turned out to be wrong   I just don't see how it could be a wiring problem that a) didn't show up for 30 hours, then showed up for a short period of time one one flight, then b) disappeared *following a network rediscovery* and hasn't returned.  I believe I was quite careful when either crimping (with the very good and expensive AFM8 crimper, although in this case the pins were already crimped by the vendor, who uses even more expensive equipment ) and inserting (with the appropriate tool) D-sub pins, and ensuring good solid connections on both ends (and in the case of the pitch servo, tying the connectors together with either zip-ties or lacing cord, I can't remember which now) to make sure they stayed mated because they're a pain to get to.  All pins were subjected to a pull test, as well, prior to insertion, and all connectors have proper strain relief.

This just smells more like a software or internal hardware (UART?) glitch to me...if it was a pin with intermittent seating, I'd expect to see the servo going on- and off-line all the time, and I don't...

 

[Dynon]

These can be tricky to isolate. A couple of questions: Are you running 5.1? If so, when the servo goes away, is it always offline? Or do you ever see connection faults? When it goes offline, does cycling the breaker (if accessible) ever bring it back)?

Any chance that you can swap the data part of your servo harnesses upstream in the panel area? That can help rule out harness issues (save for the power connections).

 

[swatson999]

Running 5.1

The servo has only "gone away" that one time, so I'm not sure I can answer that question.

I *never* see connection faults...it's worked flawlessly until that one incident, with all software versions over the last year (during the build and now flying).

I cannot cycle the breaker in flight (no breakers...only fuses, and a single fuse for both servos).

I'll have to check the exact harness configuration, but I don't think I can swap them upstream...I'm not at the hangar, but IIRC, I received the two-servo harness already made such that it's split at the EFIS connector, with one (long) bundle going to each servo (but I'll check tomorrow) and the ADAHRS. It's whatever Stein makes for a two-axis + single ADAHRS configuration (the other network port is split to ARINC and EMS).

 

[rfazio1951]

I had the same thing on one flight a year ago. The pitch servo disappeared. I noticed it when I first started the plane and was taxiing out for take off. I shut down the skyview and rebooted it. Still no servo. I tried playing with it in the air but gave up. Later when I landed I did the network detect and there it was. Hasn't happended since. I've got 200 hours or so on my skyview and probably 150 on the servos.

 

[swatson999]

I had the same thing on one flight a year ago. The pitch servo disappeared. I noticed it when I first started the plane and was taxiing out for take off. I shut down the skyview and rebooted it. Still no servo. I tried playing with it in the air but gave up. Later when I landed I did the network detect and there it was. Hasn't happended since. I've got 200 hours or so on my skyview and probably 150 on the servos.

That's sounding pretty darned close to what I saw...close enough I'd start to suspect a common failure mode of some kind. Not necessarily guaranteed, but the "signature" sounds close enough to warrant some investigation...