GF PA 21, Instruction Manual

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Instruction manual Intended use
27
1 Intended use
The following descriptions and instructions apply to pneumatic actuators Type PA11 and PA21
with DA, FC or FO function.

These actuators actuate valves with a pivoting range of 90° through a F04/05 interface
with a maximum actuating torque of 20 Nm, and are operated by control air (2.8 – 7 bar)
from an external control source.
These actuators provide the following functions:

Double acting pneumatic actuator (DA)
 Single acting pneumatic actuator with spring for the failsafe CLOSED position (FC)
 Single acting pneumatic actuator with spring for the failsafe OPEN position (FO)
The pneumatic actuator can be mounted on any part-turn valves with an interface as defined
in ISO 5211.
These actuators are not intended for any type of application other than those listed here! The
following especially apply:

Control pressures above 7.5 bar must not be used.

The F04/05 interface must not be loaded with forces greater than those permitted by
prEN12570 (maximum retention forces for operating the valves).

Pneumatic actuators must not be operated under water.
The pneumatic actuators will function correctly only if they have been connected correctly as
shown in the control diagram.
See Section 5 "Design and function", Page 32.
Possible risks of incorrect use:

Non-compliance with the valve and drive specifications can lead to premature wear or
cause the controlled valve to fail to open or close.

Uncontrolled release of the control air can cause a valve malfunction (valve does not
open or close completely).
 Humid control air can cause premature wear, see Section 6 "Technical specifications",
Page 36.

Blocking of the vent holes can cause the drive to move too slowly or to fail to move
through its entire control range, see Section 5.1 "Functions", Page 33.
NOTE
NOTE