A: There are a wide variety of actuators types, operating modes, fail positions, and accessories offered, the most common used for industrial dampers are identified herein. Contact your local Ruskin representative for a selection specific to your application.
a. Types:
(1)	Electric (motor-operated) 24Vac/Vdc to 230Vac
(2)	Pneumatic (air-operated) 25psi to 120psi
(3)	Manual hand quadrants
(4)	Manual worm gears w/hand wheels
b. Operating modes: 
(1)	Manual
(2)	2-Position
(3)	Modulating
c. Fail position: 
(1)	Non fail-safe (fail in place)
(2)	Fail-safe (fail open or closed)
d. Ratings:
(1)	Low temperature
(2)	High temperature
(3)	NEMA 2,4,4x,7, or 9. 
e. Options and accessories: 
(1)	Position feedback (4-20mA, 3-15psi, or switches)
(2)	Pressure regulators
(3)	Manual overrides
Representative Locator LINK 
Actuators and Damper Accessories LINK