help with powering servos think i broke things :(

Hi!

I am new to Arduino boards, and am working on a project which is quite simple, I only wish to use 2 or 3 servo motors. I successfully had a single servo moving the way in which I wanted just from plugging it directly into the arduino board and powering this board from a 9v power adapter. However after researching what was required to run 2 or 3, I realized I had to run a breadboard etc, so I set everything up like this;

I stripped the cables on a 5v 3amp power supply and connected the ground and power to 2 buses on a breadboard. I connected the power from a servo to the power bus on the breadboard. I connected the ground from the servo to the ground bus. I run a jump cable from the ground bus to the ground on the arduino. I ran the signal cable from the servo to the signal pin 9 on the arduino board. Nothing happened for a few seconds. I got worried and unplugged everything. Now nothing works… I tried wiring up the servo directly to the arduino. It no longer works. The arduino will power up, but once a servo is plugged in, the power light dims dramatically and the board heats allot up at an extreme rate. I do not know if i have fried my board, or the motor…or both. Can someone please offer some advice? I have a deadline for this stuff and am getting frustrated.

Only thing I can think of is:

Are you sure the power to to servo is the correct polarity? Plus to plus, neg to neg.

Agree waltr, make sure the wiring is correct. Since you powered the servo before with the Arduino, you may have damaged the arduino before the breadboarding.

try to reprogram the arduino board with a blink or serial echo sketch, the servo board not connected, that will show if the processor chip is still alive and talking.

If everything was wired per your description, I don’t think you did anything wrong. I guess it might be possible that one power brick tied it’s output ground to the mains ground and the other brick can’t tolerate that but that’s pretty unlikely.

The thing to do right now is use a DVM and check the voltages from your common ground w/o the servo or Arduino plugged in. Verify they are the 9V and 5V you think they should be. You can then plug in the Arduino and test it (or power the Arduino off the USB power). Write a simple sketch to toggle pin 9 on and off at some slooooow rate. Connect an LED and resistor in series to pin9 and see if the LED toggles on and off (or use a DVM). If it does then pin9 is still working and it would seem the servo is bad. It’s not clear to me why that should be at this point though and so I’m uncertain about what to do next. You mentioned 2 or 3 servos so I assume you have another “good” one lying about. You might go back to your original setup, running the Arduino and servo off the Arduino voltage (no external 5V supply) just to verify all the pieces work. After that … I’m just not sure. Do you have a 6V lantern battery handy … or some other 4-6V battery pack that could be used just to power the servos ?

OMG ok problem solved, I reversed to polarity like an IDIOT and destroyed 2 servo motors…

while we are on the topic of servo motors…does anybody know of any brand/model that is like…substantially quieter than the regular run of the mill…? they are quite loud for the project I am working on…? Sorry for off topic, maybe I should start a new one

Ok. We’ve all done this which is why I suggested that as the problem (you now know how I knew).

There are plenty of higher quality RC servos but they do cost more.

Search the RC airplane/car online stores for servos. Look for ones with ball bearings and precision gears.

servos of the high-end modelling variety that feature ball-bearings instead of bushings are quieter…also, sorta ironic, but get servos with nylon gears instead of the higher priced metal-gear servos… So, nylon geared, ball bearing servos would be quietest.

It sorta like Buying a 4x4 truck with little skinny passenger car tires, lol.