The D-4070 has a first-stage nominal spring range of 3 to 6 psig (21 to 42 kPa) and can be furnished with a second-stage spring range of either 9 to 12 psig (63 to 84 kPa) or 11 to14 psig (77 to 98 kPa). The control air pressure for normal HVAC operation is 0 to 20 psig. The total stroke of the D-4070 is2-3/4 in. (70 mm) and is adjustable from0 to 50% during the first stage of operation.
The D-4070 incorporates several internal and external features that add functional flexibility. A two-way swivel connection on the actuator cylinder head provides nonbinding movement. All actuators have a telescoping piston rod for easy linkage of the damper for attachment points up to 8-3/4 in. (214 mm) away from the face of the actuator. A swivel ball joint and slotted crankarm connector are furnished on all actuators for optional methods of linkage to the damper.
When used with proportional control, the damper size is limited by the torque requirement.