Current reversed on compressor spike controller

[mechanicalbrain]

I would like to thank everybody for their help. We finally got everything up and running. What ended up happening was a series of unrelated events that caused only the compressor to stop working. First our pwm cables to the had been damaged and kept causing trouble. At this point it worked 50% of the time. After replacing these the compressor stopped working all together. This is when we started this post. All of a sudden it decides to work this morning (still don't know why?) after extensive testing with a multimeter but it wouldn't turn off!! Our code to regulate it didn't seem to work. After testing the pressure sensor we found that the pwm for it was plugged in but it wasn't getting power! Well thats when we remembered that not all our pwms were long enough to reach the controller so instead of splicing them and soldering two together we had just connected them and taped them and the splice had come apart! After fixing that and reinstalling our original code we finally got it to work properly.

In summery Ive learned two things. One: make sure everyone next year knows the proper way to wire (and make sure were super neat). Two: I REALLY hate pneumatics!

[sciguy125]

It seems that Murphy decided to pay you a visit.

[Alan Anderson]

Originally Posted by mechanicalbrain

...I REALLY hate pneumatics!

Why? Everything you mentioned breaking was electrical.

[Al Skierkiewicz]

Originally Posted by mechanicalbrain

Well thats when we remembered that not all our pwms were long enough to reach the controller so instead of splicing them and soldering two together we had just connected them and taped them and the splice had come apart!

A good way to connect two PWM's end to end is to tie a knot and then tape the connectors and knot.

[Alan Anderson]

Originally Posted by Al Skierkiewicz

A good way to connect two PWM's end to end is to tie a knot and then tape the connectors and knot.

That's true of just about any in-line connector. We regularly tie overhand knots in extension cords and serial cables when we have to use more than one. That way the tension on the wires tends to pull the connections tighter instead of apart.

[mechanicalbrain]

Yeah thats what im going to do now. And the reason i hate pneumatics is that murphy would have a field day with them. Their are too many weak points in a pneumatic system that can cause the entire system to fail. At least if you loose a drive motor it only hampers you (this is dependent on the robot)!