Let's Collaborate: FRC Electrical/Systems Troubleshooting Manual

[Al Skierkiewicz]

I posted these in a different thread so I am copying them here...
Here's a couple of hints that are common problems...
1. Whiskers at the termination point. A stray strand of wire, in a connector, touching an adjacent wire in a connector (PD to Crio and sidecar power). This is easily handled by not stripping the wire too long. Twist the wires before insertion. If there is any copper showing when you are done, hold the wire in one hand and pull down on the insulation towards the connector with your other hand. The insulation will stretch and cover the exposed copper.
2. Use heatshrink to cover up exposed wiring. It is cheap and fun to use.
3. Insulate the battery terminals when you are finished terminating the power wiring. The battery is capable of 600+ amps when fully charged. It won't kill you but it can cause a halacious fire in the right setting.
4. Use the "tug" test on crimped terminals. Pull on the terminal with all your might, it should not pull off and it should not move. A ratchet crimper will cure most of these problems and costs about $50.
5. Tie down all wiring near the termination (PD, connector, speed controller, Spike, motor, etc.) The robot moves, sometimes violently, so don't depend on the terminal or connector to take care of itself.
6. Inspect every connection after every match. Use your eyes, ears and nose.
7. Color coding everything makes troubleshooting so much easier. See some of my other posts for details and our motor sheet is on here somewhere as well. A sheet with color codes, motors, servos, PWM inputs, breakers and whatever else the team needs for distribution to electrical, mechanical and software keeps everyone on the same page.
8. Make sure that every student that works on the robot is knowledgeable and trained or is working with someone who is. It takes time but wins matches.
9. The robot rules for wiring includes a color code. It is there for a reason. If a sponsor wants to donate wire make sure they know, you can only use certain colors.
10. See #6 above, repeat as often as you need to feel safe and secure.