why does my a/p disconnect and electrics go crazy when climbing or desending (zibo 737)

[craig331]

hi, i hope someone can help, i reinstalled x-plane after being off for about 8 months, installed all my fave mods and stuff etc, in the sim, after doing all the prep stuff, i get in the air(flying on vnav/lnav via fmc) when i get to around 20,000 ft a/p suddenly disengages the red and yellow warning light flash, and the gen lights overhead flash, its like the electrics are going crazy, i have to hand fly for a while until it stops, then i can engage a/p again, this will usually and randomly do this 3 to 4 times until i reach cruise level, then its fine until desend, then the same happens randomly on the way down,
ive really tried everything i can think of, ive spent the last week trying to sort it out but now its just making my blood boil.
now im pretty rubbish when it comes to pc and technology lol, but im sure every thing is installed correctly, ive read the zibo manual about 20 time about calibration augmetation set to zero and all that stuff, and avitab settings but now im out of ideas, i would appreciate any help........

[SRΑKA PTAKA]

The same thing happened to me twice, I don't remember exactly why. Resetting the failures and setting up a new flight helped

[craig331]

Thanks for the reply, ive done this many many times, ive attempted probably about 20 flights and this happens everytime lol, and fix failures in the avitab ive tried, ive also unchecked the failures box in the main menu. this is a proper head scratcher for me, thanks anyway......

[SRΑKA PTAKA]

Cool, no need to thank you, I did not help. But at least now you know that others have similar problems too. Greetings :)

P.S.:

Why PMDG 737 with FSX can be trouble-free and unproblematic, and not ZIBO? With all due respect to ZIBO. PMDG is great and unrivaled. The problem with PMDG is only with the old AIRAC databases and the old world map navigation data in FSX. PMDG has a perfectly and properly working HGS (HUD) system

[Prezidentas]

Originally posted by SRΑKA PTAKA:

Cool, no need to thank you, I did not help. But at least now you know that others have similar problems too. Greetings :)

P.S.:

Why PMDG 737 with FSX can be trouble-free and unproblematic, and not ZIBO? With all due respect to ZIBO. PMDG is great and unrivaled. The problem witch PMDG is only with the old AIRAC databases and the old world map navigation data in FSX. FSX has a perfectly and properly working HGS (HUD) system

well thats because PMDG costs $100 and zibo does not. you kinda get what you pay for.
I never received such failure with electrics, maybe you could make a video with it happening?

[craig331]

https://steamcommunity.com/sharedfiles/filedetails/?id=2391562207

[craig331]

https://steamcommunity.com/sharedfiles/filedetails/?id=2391563092

[craig331]

hi, i cant do the video, as i said im not very pc minded, but i will keep trying,i managed to put the screenshots on, dunno if this will help, this was on desent, but it happens on climb aswell....

[SRΑKA PTAKA]

If I understand the friend above (the author of the post) correctly, he probably means what happened to me twice. Namely: the relay (contactor) from the electrics starts to go crazy, as if it was interrupted by the coil connecting the main busbars of the electrics. It turns the main circuit on and off with a frequency of about 10 Hz. In other words: The electrics are disconnected and reconnected with a frequency of about 10 Hz. It gives the impression that the relay coil is vibrating. The frequency of the sound is similar to that of the stall alarm. Of course, during this event, the autopilot is disconnected. It can be turned on again when the relay calms down and ensures a stable connection of the main electric bus

Craig, I'm right?

I don't have any recordings of this happening to me, nor can I make it happen because I don't know what's causing it. I would share the video if I had. But unfortunately I don't have it

---

Hi Red Star Gopnik my friend. Indeed

It's a pity that PMDG doesn't release the B738/9 addon for X-Plane yet

[craig331]

hi, yes thats exactly what happens, and overhead, its says source off bus i think, and makes the noise you describe, it will do this for maybe a minute or 2, and then stops, allowing me to re-engage the a/p

[Prezidentas]

I'd check x-plane control bindings, could it be that you have some random input set on the electric bus switches? Also, craig, FLT on the engine starters are for mid-flight relight of the engine, not for normal flight :P just keep them at OFF when in calm cruise

[craig331]

yeah i will check to see if i can find anything in the bindings, cheers, and i didnt know that about the engine switches, i thought that FLT was turned on from cont after takeoff, but i will bear that in mind from now on, thanks

[SRΑKA PTAKA]

Bingo! Red Star Gopnik has solved the problem! Gopnik, as you wrote this, you reminded me that the problem was when I was flying with the IGN switches in the FLT positions. It was you (if I remember correctly) telling me not to do it. The FLT position is not for normal flight

During flight, ignitors should be in the OFF position

Originally posted by https://aviation.stackexchange.com/questions/74824/what-are-the-cont-and-flt-modes-of-the-737-start-switches:

FLT mode turns both igniter systems on, the better to help keep the engines operating under adverse conditions, or maximise the chance of a successful midair relight. In the real world, FLT mode is used only in conditions posing a significant risk of engine flameout (for instance, extreme turbulence or very heavy rain), or if a flameout has already occurred and one or both engines need to be restarted in flight - not for high-altitude cruise flight in general.

Set ignitors to CONT positions when you prepare to taking off or approaching

greetings

[Prezidentas]

Originally posted by SRΑKA PTAKA:

Bingo! Red Star Gopnik has solved the problem! Gopnik, as you wrote this, you reminded me that the problem was when I was flying with the IGN switches in the FLT positions. It was you (if I remember correctly) telling me not to do it. The FLT position is not for normal flight

During flight, ignitors should be in the OFF position

Originally posted by https://aviation.stackexchange.com/questions/74824/what-are-the-cont-and-flt-modes-of-the-737-start-switches:

FLT mode turns both igniter systems on, the better to help keep the engines operating under adverse conditions, or maximise the chance of a successful midair relight. In the real world, FLT mode is used only in conditions posing a significant risk of engine flameout (for instance, extreme turbulence or very heavy rain), or if a flameout has already occurred and one or both engines need to be restarted in flight - not for high-altitude cruise flight in general.

Set ignitors to CONT positions when you prepare to taking off or approaching

greetings :winter2019happyyul:

wait, so the igniters were disconnecting the engine generators? good thing I noticed it then lol

[SRΑKA PTAKA]

I don't know if igniters are the direct cause of this, but yes. Indeed. In ZIBO, when the IGN's it in the FLT position, such miracles happen (the Main Bus goes crazy and of course disconnects important systems)

[craig331]

hey, i just did a flight with your advice and it was fine yipeeeee lol, lots of thanks to both of you, turns out to be human error haha, i'm not sure if this is a new feature, but when i used to fly zibo im pretty sure i always put the engine switch to FLT after T/O, but then again maybe not, i dont really understand what each switch setting is actually for, apart from grd for when i fire the engines up... anyway it doesnt really matter now, i can get back to flying, again many thanks