Measuring The Motor Transition Time V1 - Siemens SIMATIC S7-1200 Function Manual

Using PID_3Step
5.3 PID_3Step V1
5.3.2.5

Measuring the motor transition time V1

Introduction
PID_3Step requires the motor transition time to be as accurate as possible for good
controller results. The data in the actuator documentation contains average values for this
type of actuator. The value for the specific actuator used may differ.
You can measure the motor transition time during commissioning if you are using actuators
with position feedback or endstop signals. The output value limits are not taken into
consideration during the motor transition time measurement. The actuator can travel to the
high or the low endstop.
The motor transition time cannot be measured if neither position feedback nor endstop
signals are available.
Actuators with analog position feedback
Proceed as follows to measure motor transition time with position feedback:
Requirement
● Feedback or Feedback_PER has been selected in the basic settings and the signal has
been connected.
● An online connection to the CPU has been established.
1. Select the "Use position feedback" check box.
2. Enter the position to which the actuator is to be moved in the "Target position" input field.
The current position feedback (starting position) will be displayed. The difference
between "Target position" and "Position feedback" must be at least 50% of the valid
output value range.
3. Click the
Result
The actuator is moved from the starting position to the target position. Time measurement
starts immediately and ends when the actuator reaches the target position. The motor
transition time is calculated according to the following equation:
Motor transition time = (output value high limit – output value low limit) × Measuring time /
AMOUNT (target position – starting position).
The progress and status of transition time measurement are displayed. The transition time
measured is saved in the instance data block on the CPU and displayed in the "Measured
transition time" field. PID_3Step will change to "Inactive" mode once transition time
measurement is complete.
Note
Click on the icon
measured to the project.
154
"Start transition time measurement" icon.
"Upload measured transition time" to load the motor transition time
Function Manual, 03/2017, A5E35300227-AC
PID control