pic: 1538 Wiring 2/4/2013

Our electronics board mid-build season. Hopefully it can provide some insight into our style of wiring.

Very nice. May I ask how you manage PWM lengths? Are they custom made or do you just hide the extra cable very well?

Custom-made. We estimate the lengths with about 1" extra when we’re laying out the cables, and then cut to exact length when we terminate them.

Hehe, I like the battery box filled with several hundred dollars worth of modules :smiley:

This is very impressive, Great job! How did you guys manage labelling wires?

Good documentation and little changes helps keep labeling unnecessary. Unfortunately we haven’t mastered this technique yet :ahh: :frowning:

I agree that good documentation is key, but even with that labelling is a necessity. It eliminates the risk of a mistake being made if a component has to be swapped. From experience, I can say that having labels at either end of our wires made my life a whole lot easier at competitions when I was on my team’s pit crew.

Since everything is cut to length and zip-tied down near its relevant component, it’s pretty hard to accidentally swap in the wrong cable. We’ve never had a cable fail.

Doesn’t mean they won’t. On our practice robot we had a PWM short to 12 volts and it caught fire. It killed a victor, the PWM and the sidecar. Had our PWMs not been labeled a 5 minutes swap could have taken a very long time

Edit:Moral of the story: Label everything! Especially the little cables to festos. When you have 6 festos and 2 breakouts things get real hairy real fast if they aren’t labeled

How do you terminate the PWM’s? Is there a special tool for that?

Yep, we use it and love it.

Awesome job! The neatness of the wiring is great. Not everyone understands the vaue of it but in the real (working) world where someone is paying for a wiring job that is what they want to see. One sugestion: we have started using wire duct, McMaster Carr P/N 75835K74. It takes up some space but it makes wiring and changing soooo much easier. It eliminates the need for custom PWM cables. I would also highly recommend labeling the wires. Our labels are determined by the line number that they start at on our schematic so they can be easily found there. This is helpful also when you have some components far away from the electrical panel.

One question: How are you isolating the C-Rio? We use Lexan but yous seams to be mounted on aluminum.

Your wiring is awesome! Even when we spent a good week planning our board and wire routing it still wasn’t that neat and we ended up with bundled wires. The metal you used for the board looks like a nice alternative to polycarb and having to drill holes.

We use 1/16" rubber adhesive backed rubber sheet. It’s underneath the cRIO.

I’m not a huge fan of labeling where it isn’t necessary, especially in our application.

As Connor mentioned, cables are neatly ziptied and cut to length.

At the San Diego Regional, we happened to have a metal shaving short out our digital side car, meriting a complete replacement. The digital sidecar was replaced and tested in under 2 minutes. Not many teams can replace a fully loaded DSC in that time even if it were labeled.

It’s just personal preference.

I count 12 motor controllers, but there are only 10 PWMs in the digital sidecar. Are you running two controllers from the same PWM?

I love the neatness. How do you keep it neat when you use light sensors and solenoids?

Two PWM signals each go to two speed controllers. You can see the Y-splices where the cables round the corner to the Talons with fans. Those are obviously intended for the drive motors.

I love the neatness. How do you keep it neat when you use light sensors and solenoids?

The motor wiring, control system component power, and heavy battery connections are also missing. I’d enjoy seeing how they were kept from detracting from the neatness. Would you mind if I came over and took a look at Championship? (Congratulations on another San Diego Regional Chairman’s Award, by the way.)

I’ll try to get a photo from our competition robot this weekend. The solenoids are tricked to get right.

Please, feel free to take a look. Things do get more crowded, but overall, the board is still neat.

What 1/16" rubber adhesive backed rubber sheet do you use? We bought a roll of Bump-On from McMaster-Carr this season, and the stuff costs a fortune.

The rubber isn’t 1/16" thick. It’s a 1/32" thick sheet of adhesive backed silicone rubber. The McMaster part number is 8622K41. Apply the adhesive side to the bottom of the cRIO chassis so that it travels with the cRIO. We covered the bottom of both of our 4-slot cRIOs and still had a lot left over.