Technical, Techniques, Hints, and Tips > Radio Equipment
Servo voltages
Tug-Kenny RIP:
Another techie problem has come my way (why me)
I decided to raise the motor voltage to 12 volts instead of 6 volts. I have changed the servo 4.8 volt battery for the old 6 volt battery and invested in a 12volt 7Ahr. for the motors (I 'm not sure if it will float now !!)
I wired it up on separate supply lines and now, when the motors are accelerated I find the servos start judderring all by themselves until max speed is reached, then it all cuts out with the ESC's flashing their lights.
My question is this. What voltage is supposed to be on the servos, as this also runs to the ESC's. I seem to be getting half a volt coming back up the 6 volt line from the 12 volt battery. :(
Hope you can help
Cheer...Ken
Shipmate60:
What ESC's are you using and have you disabled the BEC if the ESC's have one?
Bob
FullLeatherJacket:
Hi Ken
Most radio systems run from 4 cells. If they are rechargeable then that is nominally 4.8 volts, although a fully-charged pack can register over 5.5 volts. With alkaline cells it's 6 volts, but that drops quite quickly under load.
I'm not sure what you've done to cause such a commotion, but if I were you I'd completely divorce the power supply to the motors and ESC's from that to the receiver and servos. If the model you are talking about is Aziz then you have a shed-load of room for a decent 4-cell NiCad or NiMh pack dedicated to the receiver and servos. More folk than I could count have come to grief by trying to power the motors and radio from the same supply. I've been lectured until my nose bled about earth-loops and other things I couldn't even imagine, so I try to adopt KISS every time (Keep It Simple, Stupid). Have a shufti at the Mayhem site here:
http://www.modelboatmayhem.co.uk/Common/Electrics/Images/setupsA4JPG.jpg
Keep the power cables for the motors etc well away from the receiver and antenna wires, and make sure you have soldered suppressor capacitors across the motor terminals (details elsewhere on this forum, or PM me)............and avoid BEC.
Works for me, but suit yourself anyway.
Mankster:
Most modern servos will run happily off 6 volts though there lifespan may be reuced slightly. RX's should be fine on 6v aswell. Make sure you have disabled the BEC on the ESC (disconnect red wire to the Rx), and try fitting suppressors to the motor.
HS93 (RIP):
I ran model cars for a long long time and we would try to use 6v to keep the servos as quick as possible in cars they did not last very long due to impact I still run all my stuff of 6v in boats i don't like becks in boats so run on 5 nicads I only do this so if the drive battery is going flat or you ask to much of it you don't get glitches I did look on the futaba web site and found this though
http://www.futaba-rc.com/faq/product-faq.html#q109
My expensive, ball bearing servos 'buzz', 'humm' or 'chatter', especially when I first turn on the receiver.
MY standard servos never did this. What's wrong? What do I need to do?
We often receive calls from customers who will mention that they notice "servo chatter" in their ball bearinged servos.
Always check your linkages and set ups for binding, servos fighting each other on the same working surface, and bad extensions to be sure that there's no problems in your physical system.
Assuming there is no binding or other issues, buzzing is a common and harmless occurrence, and indicates that your servo is "checking" itself for true center. There will many times be an audible "buzz" from their servos, even when there is no noticeable movement. And this is also harmless, as when the plane is airborne, the wind over the control surfaces, and thus load on the servo itself, will correct this small amount of vibration and noise.
Many times if a modeler is using a 6 Volt receiver battery, or a completely fully charged battery, they will notice buzzing, but, when the voltage drops slightly with some amount of load, the movement and noise subside. This is commonly known as 'a hot charge' and again is perfectly normal and will subside under loads and particularly in flight
there was allso this that may be usefull to people with fast boats
Why are S3003/S3004 servos not to be used in helis?
Both the S3003 and S3004 use a direct drive potentiometer. What that means is the output gear is connected directly to the potentiometer. Since the output gear is connected directly to the pot it is very possible that vibration will damage the pot. This is why we do not recommend these servos to be used in helis. Helis generate a very high frequency vibration due to the high rpm of the engine and the close proximity of the engine to the servos.
Peter
Navigation
[0] Message Index
[#] Next page
Go to full version