losi 8ight 2.0T servo problem - RC-Monster Forums

**losi 8ight 2.0T servo problem -** 01.20.2011, 06:53 AM

Hello!

I installed new mamba monster system on my truggy.
I have new SAVOX servo: SC-1256TG.
And I use Spektrum DX3.0 Tx with SR3000 Rx.
I can control the forward/reverse well, but when I touch the steering wheel left or right – the motor stops and the servo does not work as well.
Without touching the gas trigger: when I steer left or right, the servo moves a little bit, and then stops. The green light in the receiver turns off, and the motor starts to works alternately.
What should i do? what is the problem here?
Thanks alot guys.

Idan

slimthelineman · 01.20.2011, 09:52 AM

Seems like alot of people are having issues with the savox servos lately. Your servo is drawing too much current and causing the receiver to reset. Check to make sure there is no binding in the steering linkages or try another servo to see of you can isolate the problem. Could be one of those two but keep us posted, good luck!

ZippyBasher · 12:24 PM

I am having the same problem (Bluebird Servo) I contacted Castle about it and, they cant do anything but ask you to buy some more of there BEC products... The Monster BEC is not up to the Task of Higher power servos. Which is kinda Lame considering that the ESC can take a hell of a lot of motor, but not servo...

I fixed the issue with a 16v 1000m Capacitor bought at Frys electronics for $1.99, solder it to an old servo lead and plug it into the Battery Slot on the Receiver. This will keep the Receiver from Blacking out...

Although I think a 10v 1600m would be better, but 16v was the lowest voltage they had.

Kcaz25 · 01.20.2011, 01:04 PM

My MMM powers a monster of a servo. 333oz torque. CLICK I have the version without programing. They put Hobbico on mine. Its made by hitec.

BrianG · 01.20.2011, 01:10 PM

I've been running the bigger ACE servos in all my 8th scale rigs just fine as well.

It is important that the servo doesn't hit any mechanical limits because the servo motor stalls, and pulls a LOT of current. I always set the EPA correctly to avoid this.

ZippyBasher · 01:20 PM

It is wierd. My Hitec 7950th also runs fine without cap on the MMM. But my other servos dont like it very much. I dont really get it. I can run a 20kg/cm servo in my Rustler with a Mamba Max using the internal BEC and not an issue. When I put the Mamba Monster into that same car the Steering goes nuts. I just am glad I found a cheap fix. So now, I actually use a cap on the car that was working fine just for insurance...

Note: I also am using a Spektrum Rx/Tx.

BrianG · 01.20.2011, 01:27 PM

On just about all my setups (which use Spektrum), I also run a capacitor in the CH3 slot. Spektrum receivers do tend to be finnicky - maybe they just don't like the little switching noise present on the power line. You could also wrap the throttle cable a couple times through a ferrite donut to inhibit that noise (may have to temporarily remove the connector to do this).

ZippyBasher · 01.20.2011, 01:35 PM

Quote:

Originally Posted by BrianG

Spektrum receivers do tend to be finnicky.

You could also wrap the throttle cable a couple times through a ferrite donut to inhibit that noise (may have to temporarily remove the connector to do this).

Good Idea, I have a Turnigy BEC I Blew out with a ferrite ring. That will be a lot cleaner looking going through the ring than a zip-tie anyway!

Did you have any problems when you were not using the Caps? and what spec cap are you using Brian?

Thanks - Sean

BrianG · 01.20.2011, 01:37 PM

Actually, I don't know. I made up several caps with servo plugs a while back, so I just use them. They may not help, but certainly won't hurt. I'm using 1000uF 10v caps, and they happen to be low-ESR type (although they don't need to be since ripple currents are relatively low).

ZippyBasher · 01.20.2011, 01:44 PM

Thats the way I felt too, I got em might as well use em.

To the OP: Try a cap. Its cheap and may just be what you need.

Overdriven · 01.20.2011, 10:43 PM

I wouldn't be so quick to blame the MMM either. I run a JR9100T on my max with the CC Blower, and a 8 LED light system all off the Rx with no issues. But I'm also running a FASST system. My bro-inlaw on the other hand is running a MMM on a Spektrum SR3000, and his setup didn't like the JR650M and CC Blower if there was too much strain on the servo. Swapped in my Futaba and no more problems. He also had problems with the Spektrum RX when it was in other vehicles as well.