Major Electrical Issues and Malfunctions

To all whom this may concern:

Team 992 is having some major electrical difficulties. For some reason or another, 2 of our 4 victors are not working correctly. We have 3 connected to the Maxi Block and 1 connected via a spike. 2 of the 3 of the connected to the Maxi Blocks are spinning the fans and are blinking their respective lights, however when we try to use them for our motors, nothing is happening. We cannot determine whether or not the problem is in our victors, wiring or programming. The default code given to us by FIRST is also not responding to the victors. We have been attempting to solve the problem for about 3 hours and have come up completely unsuccessful. For any team that thinks they have a possible fix to our problems, we openly accept your suggestions.
Thank you for reading.
Team 992

Check your pwms first. We had some unconnected and got blinking victors a couple days ago. Other than that just test different things changing them one at a time scientific like. One variable at a time. We’ve had bad victors before too so if you have spares you could wire one up and test it to see if the victor is the problem but just stick to one variable.

On the matter or PWMs, we have tested and retested the 3 PWMs we are using and immediately, when we change the PWM connections between the 2 bad victors and the 1 good one, the PWM that is connected to the good victor works. We have been trying to reprogram it for about 2 of the three hours, thinking it was a programming error, but when we loaded the original FIRST program it did not work either. Thank you for your suggestion though.
Team 992

one quick troubleshoot after youcheck your pwm wires is to just hook the non working victor PWMs to the PWM header you have the working victor on. If they’re still broken then it’s a decent bet that there’s something wrong with the victors. if they suddenly work, then there’s something wrong in your code.

On reading your response, we have been testing the bad victors in the good PWM slots. There is still no response. We are taking our one remaining, new victor and using it to see whether or not it is a victor problem. Thank you for your suggestion.
Team 992

Update on electrical problems: After using the brand new victor, we have discovered that the problem we are having is within the wiring of the bot. We have a direct connection from the maxi block to the victors, and now know that the problem is contained in between those wires. For anyone that is reading this thread, what would be the best way to solve our wiring problem, with the last result being to take the entire system off and reinstalling. Thank you for reading and we look forward to hearing your suggestions.
Team 992

Since you now know where the problem is-- get a multimeter and check to make sure the wire is good. Pull on the connectors to see if they are loose. If you have spare wire, make new wires and just run them to see if the victors work.

Check your robot to see if there is bare metal touching the wire. The robot could be grounding out.

Finally, are the fuses for the maxiblock in all the way? Give them a firm push. Let us know if any of this worked

I’m not going to touch on the rest of your post for now, since others seem to be taking care of it. However, no one addressed this sentence.

You are not allowed to attached a victor to a spike. The spike can only handle 20 amps, while the victor can handle much more. Also, the spike can put out negative polarities, which will kill the victor. All the victors must be hooked directly to a fuse (the maxi block if they drive a drill or CIM motor, or the other fuse block if they drive a different motor).

Please post here if you have any other questions. Also, go to the chatsworth competition, and ask for help there. People there should be able to help you faster then anything over the internet.

try turning your robot off and check the wires for continuty with an ohm meter

one common mistake that people sometimes make is to crimp a terminal on with the insulation pushed into the metal part of the terminal - the terminal will feel good and snug, but there wont be any electrical contact.

also , make sure you smaller fusebox has power and ground all the way back to the battery.

BTW- it is possible to push the PWM cables into a victor at an angle, so the pins do not go into the mating contacts - it will look seated, but there is no connection

when the yellow light on the victor blinks that means it is not getting any PWM data from the RC. This can be due to:

  1. the pwm cable being backwards at one end (common mistake)
  2. the OI is not on, or the OI competiition adapter is in ‘disable’
  3. something in your code is not putting out PWM commands to those pin - this can be checked with a servo - if you plug a servo into the pwm and it works, your code is ok and you have a wireing problem.
  4. the laws of physics were repealed and nobody told you :c)

Have you tried calibrating?

Center the joystick, press and hold the CAL button, move the stick all around while pressing, then center the stick and let go.

Also, do you have a jumper on the AB or BC setting?

why were you guys connecting a victor via a spike anyway? Vics and spikes have two totally different functions, i can’t find an instance where both would be required.

Have you tried testing the vics alone? Hook it up to a stand alone cricuit without the rest of electrical stuff and see the vics are working.

I would first make sure the polarity is good on everything. I would then take the old multimeter and check each step of the way starting from the battery. Once you find something that looks wrong, address that problem.

Again, I cannot stress the concept of logic. On my team, sometimes we just map out all the problems and alter them all at once. This doesn’t usually solve the problem and also fails to help you learn anything or get closer to it. Change one variable at once!

What you describe is one of the problems I anticipated when using these blocks. The entry for wiring is meant to handle anything up to a #4 wire for the stock block or a #2 for substitute block. When using #10 with these blocks, it is very easy, I repeat, very easy for the strands of the wire to work up the sides of the entry and not be connected. This leaves you with the equivalent of a much smaller wire feeding the circuit. (Maybe as small as a #22) This high series resistance develops a considerable voltage drop at high currents. If the suspect Victors are feeding the Chalupas or drills or even the FPs then it is conceivable that poor connections are dropping all the available voltage and none is left to feed the motors. See my post earlier in the year about doubling or tripling the wire termination when using the supplied maxiblocks and power distro. It appears you have done the right troubleshooting so far. Believe what it is telling you and concentrate on the wiring.
Are you going to Midwest? I will be there with Wildstang and also inspecting. If you are there come and find me and I will help. Have the pit announce page me if you need help.