Actuator not Tracking Control Signal

Issue

Actuator not Tracking Control Signal.

Product Line

Field Devices

Environment

Actuator typically controlling a damper or valve

Cause

This problem is usually traced to one of three common problems:

  1. Insufficient power to initialize actuator.
  2. Incorrect control signal.
  3. Actuator is bound.

Resolution

Verify the associated troubleshooting/resolutions with reference to the numbered causes above:

  1. Insufficient power to initialize actuator. Verify transformer capacity is above required power up inrush load. To determine if this is the problem, check published VA requirement. When multiple devices are powered from a common transformer, disconnect all other devices from transformer output or use isolated transformer.
  2. Incorrect control signal. Verify correct control signal is selected for the actuator. Verify actuator operation by using a Loop Calibrator such as the Fluke 789 to simulate the control signal. If the actuator tracks the simulated signal, the problem is at the controller or in the wiring.
  3. Actuator is bound. Verify actuator motion matches the controlled device. Is the actuator trying to close a valve or damper that is already closed?