glitching servo

[efirestormer]

Hi everyone ,

Got a noob question to ask......

I've got a Genesis boat with the following set-up:-
Leopard 4082 1600 kv (Single motor)
Seaking 180 a esc
6s lipo configuration 3s X 2 (in series) Zippy flightmax 40 c 5000 mah each
Flysky GT3B
SpringRc SM-4315M servo
Specs:
Basic Information
Modulation: Analog
Torque: 4.8V: 213.4 oz-in (15.37 kg-cm)
6.0V: 231.3 oz-in (16.66 kg-cm)
Speed: 4.8V: 0.18 sec/60°
6.0V: 0.16 sec/60°
Weight: 2.12 oz (60.0 g)
Dimensions: Length:1.65 in (42.0 mm)
Width:0.81 in (20.5 mm)
Height:1.56 in (39.5 mm)
Motor Type: ? (add)
Gear Type: Metal
Rotation/Support: Dual Bearings

Sorry to be so longwinded but I reckoned giving more info is better than less

Ok this is my question, I had been running this set-up for a few times without any problems but lately the servos had been glitching even before running on the water (upon start-up). At times, it would be easier to turn one side (right) and the servo would take sometime to take effect when I turn the tx wheel left.

I read in a few posts about receiver packs & voltage regulator etc etc but it made me more confused

What could be my problem and how should I rectify it?

Thank you.Photo0117.jpgPhoto0116.jpg

[kingwrench]

There are allot of causes of servo related glitches. First off I would test all the obvious, mechanical condition of the servo no striped gears, chaffed or pulled wires, properly charged and load tested lopo battery. Then I would isolate the bec , remove it from the RX, use a 4.8 volt RX pack plugged into the receiver and see if the problem goes away, if it does you can install a shunt around the bec leads "the SC wire" to help remove the noise. If it does not correct the problem, start testing the RX with the SC unhooked and using the separate RX 4.8 battery plug the steering servo into the throttle channel and test the servo movement using the throttle channel on the RX and see if it still glitches< assuming you do not have a servo tester. If the troubles go away you have a bad RX channel. If the problems are still there, you could have a bad RX/TX or Servo. This is where a good tester helps in testing. You will need to start swapping out known good parts until you have located the problem

[efirestormer]

kingwrench,

thanks for the insights.
which 1 is the "sc" wire & what is it supposed to do??

could it be that the esc is giving too much power to the servo thru the rx.

could u point me to any good links (posts) on this matter... (video or pics would be nice too)

I'm quite a dummy really and having a hard time understanding the electronics associated with these boats.

appreciate the help rendered man...

[gb tiggycat]

AS Kingwrench says, the T180 BEC function is reckoned to be an issue at power over 5S. I am running a 40" deep vee with a T600 1400kv outrunner on 6S and a T180. I use a short servo extension lead between the ESC and RX with the red wire cut in the extension and a seperate battery pack for the receiver.

That way , I am only "modifying" a cheap throwaway lead instead of messing with the wiring of the ESC while getting the same result. May be worth a try as a starting point?

[efirestormer]

1) cut red wire - ok, i get it.
2) use a separate battery for servo & rx - ok, i get that too.

thank you will try.......

[Southwest]

......!

[kingwrench]

Surface radios use Channel 1 as he steering and Channel 2 for the throttle output. RXSchematic3.jpg this is the basic hook up for RX to battery and servos. Some lower amp S/C speed controller's use a BEC, Battery Elimator Circuit, this can cause issues in cheaper S/C that do not put out a nice clean 5.0 volt signal, which can cause all kinds of rx and servo related issues. This is why you try a seperate 4.8 RX batt pack as the power source to the rx and re-check for the issues.

[gb tiggycat]

Don't cut the red wire, just lift red wire tab and gentlely pull wire out and tape it back. Reason is if you need the red wire connection again, you'll have it. Now it is a bugger to redo the metal part of red wire as it is real small. DUMB!

I you read the post, it says cut the wire on the extension cable which is in effect sacrificial. you don't touch the red wire in the ESC . Effective and not so DUMB

[Southwest]

.......

[efirestormer]

Guys thanks for all inputs. No need to get angry with different opinions.
appreciate your time tho......... cheers

[gb tiggycat]

Makes no sense to cut extension red wire either. Just lift the tab in the red wire and ease the red wire out and tape back, Why waste when it takes 1 minute to remove the wire. Do what you want, just shows your common sense on your part isn't there!! Don't tell an old man stuff like that.

I am probably as old as you and have been boating successfully for some 45 years , so some common sense must be there. And possibly respect for others views , which you singularly appear to lack!

Efirestormer . Hope that which ever way you try, it cures your glitching problem

[kingwrench]

Did you locate the source of the GLITCH. Please post your test results so others may learn from your results. Thanks Lance

[efirestormer]

Sorry for the late reply. I just got my Li-Fe 6.6v receiver packs from hobbyking and wired it up accordingly. The glitch didn't go away. It was in fact a bad servo. Changed the servo and the glitch went away. Thanks to all who chimed in.

[Peter A]

Open up the servo, it may have some moisture inside and be ok once dried out. BTW I take the time to waterproof my servos as they inevitably can and will get water in them too easily.

[devo]

Anytime I've had a servo glitching it has always been one that was or had been wet if this helps anyone