Page 4 of 4
I&M V_9953_AC
©
ASCO, L.P.
160 Park Avenue, Florham Park, New Jersey 07932 www.emerson.com
Figure 6.
Auxiliary Switch Adjustment
Figure 7.
Low Fire Switch Adjustment
MAINTENANCE
Before inspection, maintenance or rebuild, review WARNING statements
on page 1.
Maintenance should include annual inspection and cleaning. Use
a mild cleaning fluid, not aggressive solvents to remove dirt and oil. Organize
a maintenance schedule based on environment and frequency of use. Check
for loose electrical and mechanical connections and replace damaged parts.
Do not remove the top cover for maintenance. There are no serviceable parts
contained inside the actuator housing.
Please unscrew the low fire set screw in 1
/
4
turn counterclockwise
increments until the unit opens when ene
rgized. Then further apply ½ turn
counterclockwise.
4. Cycle the actuator several times to verify the switch setting and readjust as
required.
5. Install the front cover. Be certain that the O-ring (if applicable) and
sealing surfaces are clean and w
ithout damage. Snug down all screws
before tightening. Torque screws to 1.4 to 1.8 N-m (12 to 16 in-lbs)
evenly
using crisscross pattern.
Emerson Classification:
Internal
Figure 6. Auxiliary Switch Adjustment
Adjust this
screw using
2.5 mm Allen
key.
Auxiliary Switch
Assembly
Emerson Classification:
Internal
Figure 7. Low Fire Switch Adjustment
Adjust this
screw using
2.5 mm Allen
key.
Low Fire Switch
Assembly
Figure
7
Low Fire Switch Adjustment
(Refer to Figure 7)
1.
Before removing the front cover, review WARNING statements on
page 1.
Remove front cover (with O-ring, if applicable). Take care not to
damage the sealing surfaces and cover O-ring, if supplied.
2. Insert a 2.5mm Allen key into the adjusting screw on low fire switch
assembly.
3. The P159A2 Series Actuator is supplied with the Low Fire Switch set
at approximately 50% of the valve stroke. Turn screw clockwise to
move setpoint towards the beginning of actuator stroke. Turn screw
counter
clockwise to move setpoint towards the end of the actuator stroke.
(One turn = approximately 15% of valve stroke).
NOTE: Do not apply excessive force to the low fire adjustment screw
while setting.
Attention: Under some operating conditions, when the low fire set screw
is adjusted to less than 15% of the valve stroke, the P159A2 Series
Actuator unit may not open when energized from the closed position.
