Talon ground

[bartv]

Hi,

Our team has mounted four talons to an aluminum backplate. When I test the ground between the chassis and the talon, I get open circuit on each of the electrical connections (good!), but the heatsink has a ground connection.

Is this acceptable? We are putting an insulator between the cRIO and the aluminum; is the same needed for the Talons?

Thanks!
Bart.

[Richard Wallace]

Check the blue box under <R37> in the 2014 FRC Manual. The inspectors will be looking for at least 10K Ohms between either (+) or (-) Anderson Power Pole terminal that is connected to the PD board and the robot chassis. You might want to check for at least ten times that resistance between any Talon terminal and its heatsink, if you will be attaching several Talon heatsinks to your robot's chassis. To be safe, isolate the Talons.

[FrankJ]

The test is to measure the resistance between the PD +/- and the frame. Any other part of the talon & ground is not controlled by the rules

In other words "there is no rule that prohibits this."

[DonRotolo]

Our team has mounted four talons to an aluminum backplate. When I test the ground between the chassis and the talon, I get open circuit on each of the electrical connections (good!), but the heatsink has a ground connection.
The heatsink has a ground connection? I'm not sure what you mean. Are you saying that the aluminum heatsink, when screwed down to an aluminum plate, is conductive? (I would hope it is; it's aluminum).

The check you MUST pass is: With the battery disconnected, measure resistance betwene the + PDB connection and metal chassis, and between - PDB connection and chassis. Resistance MUST be greater than 10k Ohms (try for much more). IF you pass that test, you're good to go.