Flowserve 10-40 39 ACCESS M Mounted Limit Switch - Manual (Page 5)

5 14848-A
9. Control Block: If control block is removed, be sure appropriate
gasket is properly inserted between block & switch base (see
Figure 1 below and Access exploded view). Do not apply any
grease to gasket, it must be installed dry.
10. Air Supply Connection: Connect air supply to 1/4” NPT
connection on control block.
11. Operation:
A. Double Acting with Control Block - Air is supplied to the 1/4”
NPT port on the block. When the solenoid is energized, the spring
loaded plunger is withdrawn, allowing the supply air to shift the
spring loaded spool within the block, which opens the supply path
to the center chamber of the actuator. Air from the end chambers
of the actuator is allowed to pass through the block and exhaust
to atmosphere.
When the solenoid is de-energized, the spring loaded plunger
blocks the flow of air to the spool seal within the block and the
spool spring shifts the spool within the block to a position which
opens the supply path to the end chambers of the actuator. Air
from the center chamber of the actuator is allowed to pass
through the block and exhaust to atmosphere.
The actuator is electrically fail-safe. That is, it will return to its de-
energized position upon electrical failure.
The unit has two independently adjustable speed control screws
which can be used to adjust the speed of operation for the
opening and/or closing stroke (see Figure 2 above). If the speed
control screws are too tight, the unit will fail to operate. NOTE:
Speed control screws are shipped from the factory in the full
open position.
B. Spring Return with Control Block - Air is supplied to the 1/4”
NPT port on the block. When the solenoid is energized, the spring
loaded plunger is withdrawn, allowing the supply air to shift the
spring loaded spool within the block, which opens the supply path
to the center chamber of the actuator. Air from the end chambers
of the actuator is allowed to pass through the block and exhaust
to atmosphere.
When the solenoid is de-energized, the spring loaded plunger
blocks the flow of air to the spool within the block and the spring
loaded spool returns to a position which allows air from the
center chamber of the actuator to pass through the block and
exhaust to atmosphere as the actuator is cycled by the springs in
the end chambers of the actuator. The end chambers are
exhausted to atmosphere at all times.
The actuator is fail safe. That is, it will return to its de-energized
position upon electrical or pneumatic failure.
The unit has one speed control screw, which can be used to
adjust the speed of operation for the closing stroke (on a fail
closed unit) or opening stroke on a fail open unit, and one port
plugged with a red plastic plug (see Figure 2 on page 5). If the
speed control screw is too tight, the unit will fail to operate.
Note: Speed control screws are shipped from factory in the full
open position.
CAUTIONS: If converting a double acting actuator to a spring
return actuator or vice-versa, be sure the correct control block
gasket is used (see Figure 1 on page 5 and Access exploded
view).
Be sure red plastic plug is installed in plugged port (Figure 2
on page 5) for spring return actuators.
C. Manual Operation - In the event of air failure, the Series 39
actuator with Access unit can be cycled manually. This is
accomplished by applying a wrench to the exposed top shaft of
the actuator and turning it in the desired direction.
WARNING: Care must be taken to ensure that the actuator is not
operated automatically while manual operation is being
performed.
If a routine cycle check is to be performed on an actuator with a
control block, the actuator can be cycled manually by shifting the
spool valve within the control block. This can be done by pushing
the override button in the control block (See Figure 2 on page 5
for location of button). Care must be taken to hold the spool valve
in the desired position until the actuator has cycled. Provided the
air supply is still on, the actuator will cycle to its original position
as soon as the manually applied pressure on the override button
is released.
Flow Control Division
Worcester Actuation Systems