Servo stopping

[Jonathan S]

All,

I have a Extreme Flight 48" extra 300 with Hitec HS65MG Servos. Fairly new less than 2 years old with less than 10 flights on the plane and servos etc.

I am using an Orange reciever with a Saterlite reciever and a DX9 Transmitter.

One of the Servo's on the wing sometimes stops working after flying. There is a buzzing noise and the one aileron does not respond to stick inputs.

If I disconnect the battery and re-connect then it works just fine.

I am worried that this might happen mid air and cause a black bag incident or worse.

How can i work out what to do next.

[Cuban8]

Lots of reasons that might cause this problem, but before delving in too deeply, if the servo is connected to the RX via an extension lead, check that there isn't a poor connection at one of the plugs - reseat or replace. I've had some weird intermittent problems in the past that I've traced to poor connections in cheap extension leads, particularly where the model's not been used for a while or stored outside in a cold shed.  Be worth eliminating that before anything else.

If that checks out and there appears to not be a mechanical problem jamming the servo, what I do in situations like this is to have another servo plugged in parallel with the suspect one via a Y lead from the common servo output in the RX - both servos working together.  If the additional servo works OK when the original stops then you can be pretty certain the original servo's shot.

 

Edited By Cuban8 on 24/07/2020 13:34:04

[Former Member]

[This posting has been removed]

[Jonathan S]

All, Thanks for the help and quick responses.

Cuban8,

• there does not seem to be any mechnical issues. i.e. it works fine most of the time.
• Pluggin in a second servo is a great idea but i cannot seem to replicate the issue on the ground.
• I will certainly check the extension lead and maybe just replace it anyway. but its very intermitten and just removing and replacing the battery seems to reset which is odd.

SteveJ

• I am moving off orange and onto Specktrum - so this is good advise just budget isues stopping it happening faster.
• I dont use a seperate BEC, its certainly a good option but only one servo was not working and battery had lots of e- left when it happened last.

[Former Member]

[This posting has been removed]

[John Wagg]

Posted by Steve J on 24/07/2020 14:42:35:

Posted by Jonathan Sharland on 24/07/2020 14:19:02:

I dont use a seperate BEC, its certainly a good option but only one servo was not working and battery had lots of e- left when it happened last.

It's not the state of charge of the battery that I am thinking of, it's the temperature of the BEC circuit on the ESC.

But wouldn't that effect all the servo's ?

When does the servo resume normal working. ? Is it possible to change the servo for another ?

I have had a servo give trouble but would start working again if jolted (bad motor or worn feedback potentiometer in servo.?)

[Cuban8]

If you could arrange to have another small servo connected up as in my post, but tucked away safely in the fuz, you can fly the model and inspect it after the flight. I don't like just changing parts and then convincing yourself that that was the problem if it appears cured - problems have a habit of tricking you into a false sense of security. Chances are that it is a dodgy servo (occam's razor) but I like proof beyond reasonable doubt!

I'm assuming that the model has independently driven aileron servos from two RX outputs.

[Brian Cooper]

Servo failure is highly irritating and inconvenient, but it is a fact of life in this game. Servos should be regarded as a "consumable" item, rather like our batteries. And just like our batteries, some last longer than others.

We should consider ourselves fortunate if a servo goes "moody" prior to dying. . At least it has given us a (rare) warning of its impending demise.

At the end of the day, replacing a dodgy servo will give peace of mind. Plus, a servo is cheaper than a whole model.