Closed-loop tension control via control of the setpoint speed by tension measurement (TensionSpeed)
The TensionSpeed function block contains control and status variables for closed-loop tension control via control of the setpoint speed by tension measurement.
Overview
Start condition
Variable | State | |
|---|---|---|
xPositive | 0 | 1 |
xNegative | 1 | 0 |
xStart | 1 | 1 |
Process status – lead speed = 0, drive at standstill:
- The xPositive and xNegative signals determine the direction of rotation, so that the drive acts as an unwinder or rewinder (xUnwinder).
- With the start condition, the drive accelerates automatically to lrSetpointStartLineSpeed using lrAccDecMax (ST_Config_General) in the direction of rotation that leads to winding of material (rewinding function).
- When the setpoint tension lrSetpointTension is exceeded, the PID controller is switched on and the rewinding function is completed.
- If "0" is specified with the lrSetpointStartLineSpeed start condition, the PID controller starts up without rewinding function.
Process status – lead speed > 0, drive rotates, setpoint reached:
- The change of the setpoint tension lrSetpointTension is done with the setpoint ramp lrSetpointRampTension.
Stop condition
Variable | State | |||||
|---|---|---|---|---|---|---|
xPositive | 0 | 1 | 0 | 1 | 0 | 1 |
xNegative | 0 | 1 | 1 | 0 | 0 | 1 |
xStart | 1 | 0 | 0 | 0 | 0 | 1 |
- The PID controller is switched off. A rotating drive is decelerated with lrLineSpeedStopDec (ST_Config_General) to a standstill.
Additional information
