Speed adjustment of an actuator for an HVAC system

1. An actuator in an HVAC system, the actuator comprising:

a housing;

a motor;

a hub configured to receive a shaft; and

a processing circuit configured to operate the actuator in at least a first speed mode and a second speed mode that is faster than the first speed mode;

wherein the processing circuit is configured to perform a calibration process for the actuator, the calibration process comprising temporarily shifting the actuator from the first speed mode to the second speed mode and driving the shaft through a predetermined sequence of positions with the actuator in the second speed mode, the actuator operating at a normal operating speed in the first speed mode, temporarily shifting to a faster operating speed in the second speed mode while performing the calibration process, and returning to the normal operating speed after completing the calibration process; and

wherein driving the shaft through the predetermined sequence of positions comprises at least rotating the shaft from a normal operating position to a first end position, rotating the shaft from the first end position to a second end position, and rotating the shaft from the second end position back to the normal operating position, wherein the normal operating position is between the first end position and the second end position and corresponds to a current position of the shaft while operating in the first speed mode.

2. The actuator of claim 1 , wherein the actuator normally operates in the first speed mode and automatically shifts to the second speed mode when performing the calibration process.

3. The actuator of claim 1 , wherein the processing circuit performs the calibration process in response to receiving an input signal.

4. The actuator of claim 3 , wherein the input signal is initiated by a user.

5. The actuator of claim 3 , further comprising a user input device coupled to the housing and in communication with the processing circuit, wherein the input signal is received from the user input device.

6. The actuator of claim 5 , wherein the user input device comprises a user-operable mode selection switch.

7. The actuator of claim 5 , wherein the user input device allows a user to select a calibration mode, wherein selecting the calibration mode via the user input device sends the input signal to the processing circuit.

8. The actuator of claim 3 , wherein the input signal is an external override signal, wherein the processing circuit is configured to temporarily shift the actuator from the first speed mode to the second speed mode in response to detecting the external override signal.

9. The actuator of claim 8 , wherein the override signal is a 24 VAC signal.

10. The actuator of claim 8 , wherein the override signal is from a controller.

11. The actuator of claim 10 , wherein the controller is a field controller.

12. The actuator of claim 10 , wherein the controller is a building management system controller.

13. The actuator of claim 3 , wherein the input signal is sent without any physical adjustment of the actuator.

14. A method for temporarily changing the speed of an actuator in an HVAC system, the method comprising:

operating the actuator in a first speed mode;

receiving an input signal at a processing circuit of the actuator;

temporarily changing the speed of the actuator from the first speed mode to a second speed mode that is faster than the first speed mode in response to receiving the input signal; and

performing a calibration process with the actuator in the second speed mode, the calibration process comprising moving the actuator through a predetermined sequence of positions;

wherein the actuator operates at a normal operating speed in the first speed mode, temporarily shifts to a faster operating speed in the second speed mode while performing the calibration process, and returns to the normal operating speed after completing the calibration process; and

wherein moving the actuator through the predetermined sequence of positions comprises at least moving the actuator from a normal operating position to a first end position, moving the shaft from the first end position to a second end position, and moving the shaft from the second end position back to the normal operating position, wherein the normal operating position is between the first end position and the second end position and corresponds to a current position of the shaft while operating in the first speed mode.

15. The method of claim 14 , wherein the input signal is initiated by a user and the calibration process is performed in response to receiving the user-initiated input signal.

16. The method of claim 14 , further comprising automatically changing the speed of the actuator back to the first speed mode upon completing the calibration process.

17. The method of claim 14 , further comprising automatically changing the speed of the actuator back to the first speed mode upon removing the input signal.

18. The method of claim 14 , wherein the input signal is from a user input device integrated with a housing of the actuator.

19. The method of claim 14 , wherein the actuator normally operates in the first speed mode and automatically changes to the second speed mode when performing the calibration process.