7-1
Chapter 7. Instructions for Top Handwheel of Actuator
7-1. Model PSA1 actuator
7-1-1. Operating instructions
To manually operate the actuator, refer to Figure 7-1 and Figure 7-2 and proceed as follows:
(1) Loosen the lock nut of the handwheel and turn the handwheel in the direction indicated
by the corresponding arrowhead mark.
As you turn the handwheel clockwise, the actuator stem moves downward regardless of
whether the actuator is of the direct action type or reverse action type.
The handwheel bears the ''SHUT' mark to indicate that the valve is closed as the
handwheel is turned clockwise and the ''OPEN” mark to indicate that the valve is made
open as the handwheel is turned counterclockwise.
(2) For automatic operation of the actuator, fully raise the handwheel if the actuator is of the
direct action type or fully lower the handwheel if the actuator is of reverse action type, and
then tighten the lock nut to secure the handwheel in such position.
Precautions: If you forcefully turn the handwheel after it has reached the mechanical
stop position, the valve stem may be damaged. Do not turn the handwheel
with forces larger than 16 kgf at the outermost periphery of the handwheel.