Discussion:
No oscillation in reverse only

Crown RR3000 with EV100 system wont go in to reverse. The directional switch closes, contactor pulls in, encoder turns and I get a very low hum from drive motor but not enough to turn the motor. No go in reverse only. Any ideas folks? I've thrown new direction switches, new encoder, new directional contactor and still this BS. Probably a card?
  • Posted 4 Apr 2012 20:59
  • By troy_m
  • joined 13 Sep'08 - 112 messages
  • Ontario, Canada
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I got it figured out. Never assume you have fixed a problem... one of the wires that I soldered on to the new pot had come off -not enough heat -so after carefully soldering it on right the Crown is up and running normally. It now has a new card, new potentiometer and both directional switches. Thanks for your input. -Troy
  • Posted 24 Apr 2012 21:08
  • By troy_m
  • joined 13 Sep'08 - 112 messages
  • Ontario, Canada
If the contacts assembly is new, and pulls in, and carries enough current to get some SCR hum, then I would be looking to the few other things that may be 'direction of travel' related. I would also get the drive wheel off the floor as we test things, and insure that the the linkage to the accelerator pot was not part of the question. I had a Hyster last month that was a monotrol pedal and when the operator pushed on the reverse side of the pedal, the linkage was adjusted in such a way that the lever stopped pushing on the pot's arm, but only in rev. my point being, this unit may have some sort of linkage problem between the joystick and the pot or a bad pot.
I would check for this problem by reading the voltage on wire 29 on the ev100 card screw connection (tb 1)and making sure the voltage is the same in both directions of the joystick sweep.
  • Posted 24 Apr 2012 20:11
  • Modified 24 Apr 2012 20:16 by poster
  • By edward_t
  • joined 5 Mar'08 - 2,334 messages
  • South Carolina, United States
"it's not rocket surgery"
Sorry forgot check the N/C contacts of the direction it will travel in, may be resistance as field goes through both contactors.
  • Posted 24 Apr 2012 12:36
  • By russell_l
  • joined 7 Sep'09 - 32 messages
  • Queensland, Australia
Swap the field cables on the motor see if it still only rotates the same direction, this will tell if the motor is capable of going the other way
  • Posted 24 Apr 2012 12:33
  • By russell_l
  • joined 7 Sep'09 - 32 messages
  • Queensland, Australia

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