Logix
®
Digital Positioners FCD LGENIM0110-0 05/16
flowserve.com
20
19
TUBING
After mounting has been completed, tube the positioner to
the actuator using the appropriate compression fitting
connectors. For best performance, use 10 mm (3/8 inch)
tubing for 645 square cm (100 square inch) actuators or
larger. See
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below.
19.1 Determine Air Action
The port labeled “1” delivers air when an air supply is
present and the relay is energized. Typically, the port
labeled “1” should be tubed to the pneumatic side of the
actuator (the side that would result in the air compressing
the actuator spring). When tubed this way, the spring is
designed to return the valve to the fail safe state should
supply air or power to the unit fail.
Tube the port labeled “1” to the side of the actuator that
must receive air to begin moving away from the fail safe
state.
If air from “1” should open the valve, set the Air Action
configuration switch on the positioner to Air-to-Open,
otherwise set it to Air-to-Close.
The Air-to-Open and Air-to-Close selection is determined
by the actuator tubing, not the software. When air action
selection is made during configuration, the selection tells
the control which way the actuator has been tubed.
If the valve is double acting, port
the valve labeled “2” to
the other side of the actuator.
DANGER:
Proper tubing orientation is critical for the
positioner to function correctly and have the proper failure
mode.
Example: Tubing Linear Double-Acting Actuators
For a linear air-to-open actuator, the
“1” port of the
positioner is tubed to the bottom side of the actuator
(closest to the valve). The
“2” port of the positioner is tubed
to the top side of the actuator. See
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source not found.
13. For a linear air-to-close actuator the
tubing configuration is reversed.
Figure 13: Linear, Double Acting, Air to Open
Example: Rotary Double-Acting Actuators
For a rotary actuator, the
“1” port of the positioner manifold
is tubed to the far side of the actuator. The
“2” port of the
positioner manifold is tubed to the side of the actuator
closer to the transfer case. This tubing convention is
followed regardless of air action. On rotary actuators, the
transfer case orientation determines the air action. See
Figure 14.
Figure 14: Rotary, Double Acting, Air to Open
Example: Tubing Single-acting Actuators
For single-acting actuators, the
“1” port is always tubed to
the pneumatic side of the actuator regardless of air action.
If a double acting (spool style) relay is installed in the
positioner, plug port
“2”. See Figure 15.
Figure 15: Linear, Single Acting, Air to Open
1
S
2
Spool Relay
1
S
2
Spool Relay
1
S
2
Spool Relay
