Led on servo signal wire?

Using Arduino General Electronics
#1

Hi,

first I would like to introduce myself, as I'm new here. I play with arduino's for a few months now, and my main usage for it is automating the house, with a Raspberry Pi as the brains of it all, running Domoticz open-source home automation software, and Arduino's for wireless sensors, 433mhz controlled light switches... Lots of fun :slight_smile:

Now for my question, I've started building a Sentry Gun for my brother's airsoft company, I need to keep things small so hope to fit everything on a small breadboard (I use a Nano for this). Now, I need to connect 3 servo's for gun tilt/pan/trigger, and would like a way to monitor the signals they receive from te Arduino... Is it OK to connect a LED to the signal wires? Servo's are powered from external source (7 V DC), and share ground with the Arduino. Arduino is powered from USB as it needs to be controlled over serial by a computer running the Processing IDE. I would risk trying it if it was a project for myself, but it's not for me and I would not like the sentry breaking down and disappoint my brother...

Thanks in advance for your advice!

Michel

#2

You would need a series resistor to limit the current, perhaps 220 ohms or more.

However the servo signal typically has a duty cycle of 5 to 10%, so the LED won't be bright, just
flicker at 50Hz or so.

#3

MarkT:
You would need a series resistor to limit the current, perhaps 220 ohms or more.

However the servo signal typically has a duty cycle of 5 to 10%, so the LED won't be bright, just
flicker at 50Hz or so.

Thank you for your reply!

Yes, I will use resistors (220 ohm), the flickering is not a problem, just want to have some visual feedback to track problems easily. I was only worried it would damage the servo's or Arduino this way...

#4