Adjustment of loop-powered pneumatic process control device interfaces

A method to calibrate an interface for use with a pneumatic process control device of a process control system, the method comprising:

• scavenging power from a loop power control signal;
• causing an actuator to move to a low range position and a high range position, the actuator operatively coupled to a movable control input associated with the process control device, the actuator powered by the loop power control signal;
• measuring position feedback of the actuator during the movement;
• calculating, via instructions executed by a processor, a positional error of the actuator based on positional measurements associated with the low range position and the high range position;
• and
• adjusting, via instructions executed by the processor, a set point of the loop power control signal based on the positional error to control the actuator.

A tangible machine readable medium comprising instructions, which when executed, cause a processor to at least:

• cause a power input to scavenge power from a loop power control signal associated with a process control system;
• cause an actuator to move to a low range position and a high range position, the actuator operatively coupled to a movable control input associated with a pneumatic process control device of the process control system, the actuator powered by the loop power control signal;
• store the high range position and the low range position based on verifying that the high range position and the low range position are within acceptable corresponding tolerance ranges;
• calculate a positional error of the actuator based on positional measurements associated with the low range position and the high range position;
• and
• adjust a set point of the loop power control signal based on the positional error to control the actuator.

A tangible machine readable medium comprising instructions, which when executed, cause a processor to at least:

• cause a power input to scavenge power from a loop power control signal associated with a process control system;
• cause an actuator to move to a low range position and a high range position, the actuator operatively coupled to a movable control input associated with a pneumatic process control device of the process control system, the actuator powered by the loop power control signal;
• calculate a positional error of the actuator based on positional measurements associated with the low range position and the high range position;
• and
• adjust a set point of the loop power control signal based on the positional error to control the actuator, wherein the set point is further adjusted based on first and second data points associated with the high range position and the low range position, respectively, the first and second data points measured by a process control sensor.