Help! My 2003 Bot compressor won't shut off

[Bduggan04]

Although it is not the most elegant solution, you can still run without the shutoff for presentations. If you can't get it fixed before a presentation, the overload valve should keep the pressure below 135psi. Note: you can not do this in the competion and should really try to fix it, but hey, if your team needs money...

[RoboCoder]

since you're talking about last year's bot, I am assuming you are using last year's control system, and last years programming language (PBASIC). if this is the case, then add these lines to your code, just before the serout command:

select rc_sw2

case 1

relay3_fwd = 1

relay3_rev = 0

case 0

relay3_fwd = 0
relay3_rev = 1

endselect


this is assuming that the pressure switch is normally closed (when 120 psi has NOT been reached). If the compressor doesnt turn on at all, swap the lines "case 1" and "case 0". hope this helps!

[Alan Anderson]

Originally Posted by RoboCoder

select rc_sw2
  case 1
    relay3_fwd = 1
    relay3_rev = 0
  case 0
    relay3_fwd = 0
    relay3_rev = 1
endselect

this is assuming that the pressure switch is normally closed (when 120 psi has NOT been reached). If the compressor doesnt turn on at all, swap the lines "case 1" and "case 0". hope this helps!

I don't think applying reverse polarity to a compressor will shut it off. The last line before the endselect should probably say relay3_rev = 0, setting both wires to the compressor to ground.

[Greg McCoy]

Originally Posted by Alan Anderson

I don't think applying reverse polarity to a compressor will shut it off. The last line before the endselect should probably say relay3_rev = 0, setting both wires to the compressor to ground.

Yeah, I believe this is your problem. You want the output of the spike to be zero, rather than -12 volts