RMC70E - Question about functioning


here is a simple question about the RMC70E.

  • Controller : RMC70E - MA1
  • Actuator : ±10V servo valve on hydraulic cylinder
  • Sensor : Digital LDT with external interrogate signal
  1. Let say the cylinder actual position is 500.0mm (on a total travel of 0.0 to 1000.0mm)
  2. The “In Position Tolerance” value is 10.0mm
  3. The “Position Error Tolerance” value 50.0mm

If the a “Move absolute” command is issued with the requested position at 475.0mm (assuming the 4 other parameters have standard values) and the cylinder refuse to move (e.g. no oil pressure at all). Does the RMC70E will be aware of something wrong ?
Since the “Target position” would be 475.0mm, the controller should send a voltage curve to follow the acceleration, speed and deceleration required to reach the requested position. But if no movement happens, does the voltage increase to 10V (± depending on polarity which I didn’t mentioned here) ?
I’m wondering if a “Following error” would be raised in that situation since the position error is 25.0mm, well below the “Position error tolerance”.

Thanks !

Yes, several errors could occur. First, I want to point out that the “Command Position” would be 4.75. The “Target Position” is the position at which the axis should be at any given moment. That is, the Target Position is the profile of the move, not the final requested position.

If the Actual Positions falls behind or ahead of the Target Position (remember, the target is always changing during the move, since it is the profile), then the following error will occur. If it falls very far behind or ahead (such as when no movement occurs), then the output will go to + or - 10V, which will cause an Output Saturated error.

if the Position Error is only 0.25 and the Position Error Tolerance is 0.50, then a following error will not occur.