Tim Woodward

MrPLC Member
  • Content count

  • Joined

  • Last visited

Community Reputation

0 Neutral

About Tim Woodward

  • Rank

Profile Information

  • Country United Kingdom
  1. Closed loop

    Hi, Thanks for the reply! My servo need 10000 pulses per revolution and the gear ration is 3.6:1 so 36000 pulses to turn the indexer shaft 1 revolution BUT because the gears are not 100% accurate there is a cyclic error. If we exaggerate the gear as a slight egg shape its possible for there to be an error depending on what part of the gear (egg) its on. Also add into this expansion and the viscosity of the oil between the teeth and its possible to get a small error. Ideally I need to drive the servo using feedback from the encoder fitted to the shaft. The same way as the system works on a lathe that has a timing belt driven ballscrew with an encoder on the ballscrew.   Regards Tim
  2. Closed loop

    Hi Gary,   No, the position isn't where i want it! in this instance the position is 190.12001 degrees but I need it to be exactly 190.0000 degrees. Some how I need to output steps to correct the error?????   Regards Tim
  3. Closed loop

    Hi Gary,   At the moment I've got my 3600 PPR encoder connected to the high speed input and displaying in degrees 360.00000 If I want my indexer to turn 180 degrees the servo drive needs 18000 pules If I output the 18000 pules the servo turns and stops but the shaft encoder is displaying 190.12001 due to the gear train inaccuracy (gears are not ground) What do you think is the best way to correct this error? I see that PLS2(887) has the ability to change the target position?  Regards Tim  
  4. Closed loop

    Hi Gary,   Thanks for the links! I've found the youtube videos very helpful on getting started. Regarding my indexer, would it be possible to use SPED(885) to output a constant pules train to my servo drive then use CTBL(882) to stop the servo when the shaft encoder reached the desired angle (pules count)?????   Regards Tim  
  5. Closed loop

    Hi, Thanks for your reply. Yes its wired up but I have no experience of CX programmer or ladder programming for that matter! Ideally I would like an example ladder showing how its done?????   Regards Tim  
  6. Closed loop

    Hi All, I'm new to PLC programming and need some help with a project! I have built a indexer for a grinding machine with the following specification....... Stepper servo motor that needs 10000 pules per revaluation. Gearbox with 3.6:1 ratio. 3600 PPR quad encoder fitted to the indexer main shaft 1:1 ratio . Omron CP1H PLC   I need to control the servo closed loop using the 3600 line encoder for feedback. Does any one have any suggestions?????   Thanks Tim