My school is just starting a new FIRST Robotics Team. How can we prepare for making an electrical subteam and what kind of knowledge should the leader be prepared with.
Well. Oddly enough, you come at a strange and new time. The FRC program is undergoing a brain change. All of the electronics are new.
I would suggest a good way would be to go to the National Instruments website and try and get familiarized with the cRyo.
Check out WPI’s resources page about the cRIO as well.
Welcome to FRC 
I would start making a wish list of tools. You will need all the standard stuff, pliers, cutters, wire strippers, screwdrivers (both flavors). I would add to that a good digital VOM like a Fluke, big wire cutters for the #6 wire, and a soldering iron. If you can buy two, then get a 50 watt and 25 watt with interchangeable tips. #6 solders better with the 50 watt but is not needed for most applications. A good crimper for solderless connectors is a must as well. There is going to be a lot more for electrical teams to do this year. You might also search the forums for another thread about tool selcection. There were some great suggestions in other old threads.
You might want to check out last year’s rules. The rules change from year to year… but not so much that reading the old rules won’t help understand the new ones.
You will want to know something about the batteries, speed controllers and motors in the Kit of Parts. You will find some information hereand some great seminars and lectures both recorded and in powerpoint format here.
Here’s onethat Al, who posted above, did. You could do far, far worse than to take advice from Al!
Jason
Make sure that not only the leader of the subteam, but everyone on the team is familliar with how you guys plan to do things. If the head honcho is not there, you don’t want people not knowing what to do.
You could even do a training session just with the basics that everyone else in this thread talked about.
I would also add that before build season you hold a soldiering clinic for the sub team and everyone learn how to properly solder wires and terminals.
Also a crimping class on how to make a good crimp and which terminals are best for which applications.
-p 
I can’t stress this enough, making sure all the connections are good and this will save you time in debugging the robot during build and in comps.
More important than learning how to crimp well is learning to check that a crimp or connection is good. If everyone reflexively tug tests the connections, a bad one won’t go undetected for long.
I may be going off topic a bit, but make sure your team gets in the habit of labeling all of your cables. It comes in real handy when you take off some parts and put them back later on. A label-maker is useful for this. Also just getting hand-written labels are all right, as long as it is legible.
Even just practice at stripping wire may save you time and money. Until you are use to it you can land up damaging the conductors by cutting in to deep.
If you have a car audio place nearby you might be able to get some off cuts to practice on. Those high powered car audio systems can use #6 and even #4 gauge wire. If you can afford the crimp terminals to spare then this would be good practice as others have suggested. 
Make sure you have a safety test ready, to make sure nobody gets hurt.
Did anyone mention crimping? Yes, it’s that important. Find and buy a ratcher-type crimper for solderless terminals, it should cost around $50, and take all the non-ratcheting type and throw them away.
Tools, like Al mentioned.
Get some wire of different sizes. Get electronic type wire- stranded with relatively fine strands, stay AWAY form electrical (house wiring - THHN, THHW, etc) type of wire, it is way too stiff. #20 for sensors, #14 for light power, #12 or #10 for big motors, red and black at least.
Practice wiring stuff with crimp terminals and screw-type barrier blocks, some switches and light bulbs or motors and batteries.
Learn why you want the thickest wire you can get (within weight limits) for high-current applications.
As someone mentioned, read last year’s rules and electrical guide.
Look at some photos of neatly wired robots. Or go to an off-season competition and look. Ask a lot of questions too.
Don
NOTE: The links are examples, **DigiKey is not the least expensive supplier **around.
At this point I think I’ll start my campaign for teams moving to wire ferrules for the power distribution board. I know they boldly declare that the WAGO terminal blocks require no crimping or soldering, but I am not prepared to believe them. Using stranded wire with this style of connection make it possible to birdcage the wire as you’re inserting it, leaving bare strands hanging out, waiting to short something. Especially if you’re constantly shuffling wires around or are in a hurry. Under ideal assembly conditions where you technician is very practiced, etc. I’m certain this is a very rare occurrence. But conditions in FIRST pits are far from ideal, and our student technicians will not be terribly well practiced next year. So wire ferrules are the answer. They crimp onto the ends of stripped, stranded wire, turning it into a solid piece of wire that won’t birdcage on you. Pin terminals are a similar option, using a standard ratcheting crimper.
Probably I’m being completely paranoid, but having my students use ferrules will give me just a little more peace of mind.
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I am 98% sure that the Wagos on the PD are not designed to accept ferrules.
I am 100% sure that the Wagos on the PD are not designed to accept tinned wires. Tinning the wires will result in a very poor connection.
Simply strip the wires and insert. The cage-clamp works best when it can push the strands a bit to grip multiple surfaces. Using a ferrule reduces the contact area.
I whole-heartedly agree that tinning wires for the PD terminal blocks is a horrible idea, just as tinning a wire to be crimped. That said…
Ahem. I’m 100% certain those terminal blocks are meant to work with ferrules, partially because we use them this way on all of our machines. Also, I refer you to pages 2 and 3 of the following brochure.
Second, a ferrule is going to increase the effective diameter of the wire, increasing the clamping force to the same clamping force a solid wire would experience. If you’re claiming the cage clamp connections should be derated for solid wires… Well the WAGO people will probably have something to say about that.
Again, they’re certainly not necessary. Just stripping the wire, fiddling the terminal open, and sticking it straight in will work. But a ferrule makes it absolutely impossible to mangle the wire strands if you get in a rush. (Provided you have the appropriate crimper and apply it properly.)
Tinning on our terminals does not work as it decreases the surface area of the contact from the CageClamp and will allow the wires to pull out. IF you use a ferrul, make sure it is a square ferrul (crimped square) as a round one will pull out just like a tinned wire.
Practice a bit with the blocks. They are easy to use and you will eliminate the bird cage issue in no time. Also, I’m not sure which series TBs you are getting, but a lot of our blocks are front entry, so you’re not loading the wires in from the side hoping you hit the hole. You actually can see what you are doing!
Yeah, I hated how the anderson’s worked like that and how wires would keep coming loose. I’m really looking forward to using these. Also, the lever nuts with a loop of wire make a great clamp type thing for holding stuff together. Like a ziptie only easily removed and reused.
-vivek
Kevin,
One of the documents you pointed to in another thread gives a variety of suggested termination methods. WAGO recommends a 1/2" strip to bare wire, a partial strip leaving some of the insulation on the end of the stranded wire so that the ends won’t catch on the terminal body, a slight addition of solder to the very end of the stranded wire to keep the bundle together, or the use of the crimp ferrule which is a square crimp or the pin termination shown in the brochure which simulates a solid wire. I believe for our use with large diameter stranded wire, I would recommend either the bare strip or the bare strip with a little insulation left in place. for most teams. If you have the spare cash for a crimper and a box of ferrules, you could certainly consider that approach.
All very good points. Amen on the rachet type crimp tool. http://www2.usfirst.org/2007comp/other/2007%20Guidelines_Tips_Good%20Practices.pdf is a lot of good information condensed in one place for all the teams, not just electrical. Hopefully, there will be an updated version in this year’s rules.
Don’t cheap out on tools, either. There is nothing worse than getting pinched on a cheap pair of wire strippers, or breaking a set of side cutters because you didn’t have a big enough set. Or struggling with 22 ga. wire because you didn’t buy a small set.
Good tools aren’t cheap, but they do carry on from year-to-year if you take care of them.
Softer, more flexible wire can be found as MTW (Machine Tool Wire) in any electrical supply house. Be sure it is just MTW, not a combination like THHN/THWN/MTW. The THHN has fewer, but bigger strands as well as a tough outer clear jacket that makes the wire stiff and you’ll end up with a snarl. The MTW has finer strands and a soft plastic jacket that holds bends and will be much neater once formed.