Siemens 331-2856 - Manual (Page 5)

POWERS™ Controls No. 6 Pneumatic Damper Actuator Technical Instructions
Document No. 155-029P25
December 3, 2004
Operation
Standard Actuator
(Figure 1)
The air tubing from a controlling instrument is connected to the actuator’s upper housing.
With no control pressure to the actuator, the compression spring forces the spring seat
and actuator shaft toward the upper housing, but is limited by the E-ring. As the control
pressure increases, the spring compression is overcome and the actuator shaft
gradually moves outward. Conversely, as control pressure decreases, the spring returns
the shaft to the position at which the air pressure on the diaphragm balances the spring
tension. For each value of control pressure there is a corresponding position of the shaft.
Table 3. Standard Actuator Components.
Item Part No. Description Qty. Material
1 047-061J Retaining E-ring 1 Steel
2 333-217 1 × 1-1/4 in. Hex Nut 1 Brass
3 — Spring Retainer 1 —
4 — Stem Guide Assembly 1 —
5 — Lower Housing 1 Aluminum
6 333-572
(pkg. of 5)
Diaphragm 1 Silicone
rubber
7 599-00413 5/16 in.-18 × 1
Large Hex Cap Screw
6 Steel
8 — Upper Housing 1 Aluminum
9 — Helical Compression Spring 1
331-091 3 to 13 psi (21 to 90 kPa) —
331-208 3 to 8 psi (21 to 55 kPa) —
331-094 8 to 13 psi (55 to 90 kPa) —
10 — Piston Plate and Stem
Assembly
1 Aluminum/
SS
11 — Retaining C-ring 1 Steel
Figure 1. Standard Actuator.
12 333-197 Stop Kit (Optional) — Steel
Extended Shaft
Mounting—Pivot
Actuator
1. Order one of the following and see Table 4 for parts lists:
Actuator: 331-3011, 331,-3012, 331-3013, or 332-3011
2. Slip the 3/4-inch (19-mm) diameter hole in the mounting plate over the damper
shaft.
3. Slip the crank over the damper shaft. With the actuator assembly to the left of the
damper shaft, an increase in actuator pressure rotates the damper blade CW
when the crank is above the damper shaft, or CCW when the crank is below the
damper shaft. See Figure 2.
With the actuator assembly to the right of the damper shaft, an increase in
actuator pressure rotates the damper blade CCW when the crank is above the
damper shaft or CW when the crank is below the damper shaft.
4. Position the mounting plate and attach it to the duct with four screws.
5. When the actuator cannot be directly mounted, drive the extended damper shaft
using the Remote Mounting Kit 331-618 and Actuator 331-2856. See Figure 3.
Siemens Building Technologies, Inc. Page 5