Siemens 331-2856 User Manual
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POWERS™ Controls No. 6 Pneumatic Damper Actuator
Technical Instructions
Document No. 155-029P25
December 3, 2004
Frame Mounting -
Type B
See Figure 8 through
Figure 10
1. Order one each of the following:
Actuator assembly: 331-3011, 331-3012, 331-3013, or 332-3011
Mounting Lug: 331-569
2. Weld the mounting lug parallel and 5/16-inch (8 mm) from the inside edge of the
damper frame and perpendicular to it. See Figure 8. Weld the lug along both sides.
The lug should be as close as possible to the corner of the damper frame to
minimize deflection. The damper manufacturer should weld the lug.
Figure 8. Frame Mounting—Type B.
Dimensions in Inches (Millimeters).
3. If the damper frame is aluminum, light gauge sheet metal, or an unusual shape, bolt
a 3/16-inch (5-mm) thick, flat piece of steel to the frame. Then weld the mounting lug
to it.
4. Attach Rocker 333-034 to blade in proper position for normally open or normally
closed damper using 2 nuts, 041-230K, and 2 screws, 030-510J. See Figure 9 and
Figure 10.
5. Attach the mounting plate to the mounting lug as follows:
a. Normally Open damper: attach the plate to the lug. Place the pivot post in Hole
b. Normally Closed damper: attach the plate to the lug. Place the pivot post in Hole
6. Fasten the clevis to the rocker. Discard the crank and other parts not used.
7. The actuator mounting plate has a tendency to pivot at the point where the lug is
welded to the damper frame when the actuator strokes. It is recommended that
some means be devised in the field to prevent this from happening. A threaded rod
attached to the mounting plate and duct wall will normally work.
Siemens Building Technologies, Inc.
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