ML6284 NON-SPRING RETURN DIRECT COUPLED DAMPER ACTUATOR
63-2505
6
Fig. 3. Mounting hub to inside of actuator.
IMPORTANT
Actuators driving in parallel may not be synchronized
with each other. In normal operation, when all
actuators are driven to the fully open or fully closed
position, the actuators are again synchronized.
OPERATION
The ML6284 Non-Spring Return Direct Coupled Damper
Actuator is designed to be used in ventilating and air
conditioning installations to operate dampers, ventilation flaps
and louvers requiring up to 150 lb-in. torque.
The ML6284 Non-Spring Return Direct Coupled Damper
Actuator is operated by an spdt floating controller. When using
an spdt floating controller, the actuator is driven toward its fully
open (clockwise
) position when the controller makes B
contact and toward the fully closed (counterclockwise
)
position when the controller makes W contact. It stops when
neither contact is made.
IMPORTANT
The ML6284 can operate with DDC controller that
emulates an spdt break-before-make switch. Do not
short-cycle the actuator. Short-cycling of the actuator
can cause premature failure.
The actuator has a position indicator to show shaft position.
As the indicator moves with the shaft, it gives an angular
representation of the damper position. There are four distinct
positions where the indicator can be placed. The indicator can
be removed (by first removing the output hub) to provide
proper damper position indication. The indicator can be
indexed to show cw or ccw open or closed, using the detents
that are 90° apart. See Fig. 3.
The ML6284D and ML6284F models provide a time-out
function that removes power from the actuator submotor if the
actuator remains in the fully open or fully closed position for
longer than a nominal five minutes. This time-out function
helps to extend actuator life.
12
12
30
30
0
60
60
90
M7875
DETENT
INSERT
INDICATOR
DETENTS
DISENGAGE
BUTTON
HUB
SLEEVE
HUB
INSERTS
POSITION
INDICATOR
RETAINING
RING
