Hello everyone, I'm using the Arduino Uno R3 board and I hooked it up to a ks0258 16-channel Servo motor driver shield. In order to power the servo motor's I need to hook up 5-6 volts of power to the battery terminal blocks. When I do this using 4xAA Alkaline KR1500 batteries totaling 6 volts, it runs fine, but after about 30 seconds, it starts to smell and when I touch the battery terminals it gets very hot. I unplugged it, re plugged it and it keeps happening. Luckily my sense of smell is keen when it gets too hot. I don't want to risk running it for longer than a minute and cause something to break. I tried to lower the voltage a bit using six 220 ohm resistors ( I know not efficient), and used the voltage divider rule to create a 5v output and, as a result, the power led doesn't even light up. I was going to use a potentiometer next, but I got a hunch that something else is going on here because it should be running fine with 6 volts. Technically, it works, just starts to get too hot for comfort. Any suggestions? Current course of action is the potentiometer, but maybe i'm missing something.
Forget voltage dividing. It doesn't work when current will be passing the divider.
Show us specs for the servo board and a drawing of Your wiring. Close fotos of the connectors to the hot parts might be useful.
Ok no problem. I attached a quick drawing of the simple voltage divider I did, plus the potentiometer i'm about to put together right now. Next is a picture of the shield I'm using, the Ks0258 keyestudio 16-channel servo driver. It's attached to the Arduino R3 Uno (which is staying pretty cool considering). If there is any other info you need let me know.
Edit- Just added the drawing as well. Also here is a great link with specs of the shield.
https://wiki.keyestudio.com/Ks0258_keyestudio_16-channel_Servo_Motor_Drive_Shield#Interface_Explanation
You can't use voltage divider like that! Don't waist pots to this. It's the same. Use a step down converter I You want to create a lower voltage!
Check that connection point closely and make sure You understand how it works in order to get good contact.
Check straps etc so there is no short circuit somewhere on the board.
Did You have any servos connected when the overheating occurs? Tried connecting the board power and no servos connected?
OK, i'll look into using a step down converter. The board is clean and laying on insulating plastic so doesn't seem to be a short. Yeah, I've tried that, and unfortunately the circuit overheats regardless of whether I have any servo motors hooked up to it. Curious though.. if this isn't a time to use a voltage divider when is? I don't understand why, or if when at all, a voltage divider could be better used than right here. I'm sure you can tell, I have limited experience on practical applications of electronics, I may know the fundamentals,but I lack experience. Regardless, can you explain when voltage dividers are better used and why it's not good for splitting voltage in this case?
Did You connect the battory wrong, battory + and - , being reversed?
A voltage divider divides voltage, not power. It just don't work for this application. Make a drawing of battory, divider and load. Assume You have a load of 1/6 Ohm. That corresponds to 1 Amp at 6 Volt. Then apply Ohms law and calculate what You get.
I don't have the time to teach You this.
Hey no worries, when your right , your right. I see what you mean, the issue arises in terms of overpowering the resistors tolerance when the load draws current. You don't got to teach, no problem. And lastly no, everything in terms of battery polarity are correct, otherwise the servos wouldn't be running. My guess is I need to step down the voltage, using a voltage regulator, or make another dc power supply source with 5-5.5 volts. Anyways, won't waste any more of your time, I got it from here, thanks.
How many servos, and which ones.
That shield has 16 servo connectors, but can it support the current draw of YOUR servos.
The shield is pictured with 16 tiny SG-90 servos (16*0.65Amp stall = ~10Amp)
Seems already borderline for a 6A screw terminal and the ? circuit board traces.
Leo..
I'm using the sg90's as well , and only two. Plus even when they are both unplugged it still overheats. It's the Uno not Leonardo
Here is how I would fault find this issue, it does require a multi meter:
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Disassemble everything to the modules - disconnect battery from Servo Shield, unplug Servo Shield from Uno.
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Use Multimeter (MM) to check voltage and polarity from battery, is battery voltage 6 volts?
When you connect MM positive probe to battery positive and negative to negative do you see a minus sign (-) on the display? if you do see this symbol try swapping the leads over and check again. -
Set the meter to continuity or low resistance scale and measure the input terminals on the shield, if you see continuity or low resistance there is a good chance the shield is faulty.
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If both Battery and Shield test ok I would then reconnect battery to the shield alone and check voltage and polarity at the terminals and also check whether it is getting hot. If voltage and polarity are fine but the terminals still overheat then the shield is faulty.
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if everything is OK after this step I would then disconnect the battery from the Shield then plug the Shield onto the UNPOWERED Uno and check continuity at the Shield battery input again continuity means a dead short.
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If every thing is ok then I would power up the Uno and measure voltage and polarity at the shield battery terminal.
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If everything is ok (no crossed polarity or strange voltage) I would disconnect power to the Uno and reconnect to the Shield and do the checks again.
By this time I would expect to have found what is causing the the problem, it really can only be a short circuit somewhere or a crossed polarity or an excessive load.
Great troubleshooting guide. I'll try it out, thanks. Good karma for you, friend.
Hi,
Try with the DMM on continuity or low resistance and the shield unplugged from everything, connect positive of DMM to the 6V positive terminal of the shield and the negative of the DMM to the 5V pin on the edge socket of the shield.
It should be an open circuit.
Tom... 
PS, Have been looking for a schematic of the shield, but haven't had any success yet.