Recalibrate ESCs on a 3DR IRIS

Picture this scenario: you are using your 3DR IRIS quadcopter drone one day, when you notice that the range of your throttle has decreased, or that your drone’s propellers are spinning at different speeds. These are problems caused by a malfunctioning Electronic Speed Controller (or ESC). Use the steps below to recalibrate the ESC and solve the problem.

Step 1
To start, remove both the battery and the propellers from your IRIS quadcopter. You will need to do both to calibrate the ESC properly.

Step 2
On the controller for your drone, push the throttle stick up as far is it will go. Leave the throttle stick in that position as you reconnect the IRIS battery and power up your quadcopter. You will hear an irritating electronic musical cue that will tell you the IRIS is starting up. Once you heard this signal, unplug the battery again. Reconnect it one more time, and you’ll hear the music again. Then, you’ll hear a long buzz tone. Don’t worry, this sound is an indication that you have entered ESC calibration mode—not a sign that your copter is about to explode.

Step 3
Push the safety button on top of the drone until it turns a solid color and the drone starts making noise. Then, go back to the controller and move your throttle stick as far down as it can go. Your drone should give off another musical tone, which is the sign that calibration is complete.

Going through the above steps should recalibrate your IRIS drone so that the throttle works properly, and the motors spin at the same speeds. Once you hear the confirmation sound at the end of step 3, simply push up your throttle to make sure that it works to get the motors moving. If it does, unplug your battery again and wait 10 or 15 seconds to reconnect it again—just to make sure it is out of calibration mode.