Using EC3 connections on my quad was a good idea...except when it applied to the AttoPilot 90A sensor from SparkFun. The goal for adding this sensor to the system was to be able to remove it cleanly if needed. The sensor pcb design was changed (from earlier pics in the Wiki) to provide a clean installation of Dean's connectors. What to do? Adapt and Overcome! Behold my solution!
And from the back of the audience I hear "Yeah? So what?" Well the 'what' is the constant challenge we as hobbyists face to take parts and components from different maunfacturers and adapt them to our uses. Have you read the thread on adding this small part? To save you the trouble of looking for it, HERE. Imagine the confusion on the part of the hobbyist who asked if the sensor should be getting hot enough to melt the solder! Wow. The first task I performed after getting a successful adaptation to EC3 was checking for a direct short of the battery connection - none was found. (whew!!) The second task was to insulate the power connections to ensure a short was not added accidently while in use (or crashed).
The solution? Hot Glue! The low temp variety of hot glue guns is cheap and cheap to use. Both sides were sealed off and then tested for mechanical strength. Next was to integrate it into the quad and set it up via Mission Planner. The above linked instructions worked flawlessly to set up the sensor. There is some confusion if you should subtract the 0.3V from the actual measured output from the PDB to the APM. I subtracted it anyway - the MP prompts said I should even if it is contradicted in the Wiki instructions.
The actual function of the sensor can be seen after the APM is reset. It can also be tested with the CLI under the 'tests -> battery ' command string. NOTE: The CLI prompts you with a "Careful" mesage. THIS MEANS THE MOTORS WILL BEGIN RUNNING! ALL THE MOTORS! I did have my propellors removed prior to making the mod but if you, dear reader, decide to add this and perform the CLI tests.. REMOVE YOUR PROPS.
What you see above is the output of the CLI while the battery test is running. Note that 'Careful' actually blends into the 'Hit Enter to exit' string. When I hit Enter, the screen stopped updating but THE MOTORS CONTINUED TO RUN! I tried various commands from 'exit' to 'Cntr-C' to 'stop battery' all to no avail. The motors stopped spinning when I clicked on the 'Flight Data' icon at the top of the screen. I suspect the command string that is sent to the APM to shift from CLI to Flight Data mode flushed the command registers of the battery test states.
The last part of this tale will be a photo of the AttoPilot sensor as installed on the quad. It is installed prior to the PDB on my system but after the arming plug harness (covered in a previous blog post HERE). Thank you for reading this far and I wish you success should you choose to add this neat device to your system.