Fisher 3570 - Page 13

Instruction Manual
D200137X012
3570 Positioners
September 2015
13
Figure 5. Bellows Mounting for Direct and Reverse Action
A1088‐1
RESTRICTOR
2
2
2
2
2
2
3
3
1
1
1
1
1
BEAM
BEAM
BELLOWS BASE
BELLOWS BASE
PEDESTAL
PEDESTAL
REVERSE
ACTION
DIRECT
ACTION
BELLOWS TOP VIEW
WITH OPTIONAL RE
STRICTOR
1—MOUNTING SCREW
2—MOUNTING SCREW
3—BELLOWS POST
WARNING
The following procedures require taking the positioner, actuator, and control valve assembly out of service. To avoid
personal injury or property damage caused by uncontrolled process pressure, provide a temporary means of control for the
process before taking the assembly out of service.
Before removing the input signal and supply pressure connections from the positioner, remove the input signal and supply
pressure sources from the connections. The sudden release of pressure can cause personal injury or property damage.
Note
Changing the positioner action might require changing the bias spring and/or the spring retainer. Contact your Emerson Process
Management sales office for assistance in determining if a new bias spring and/or spring retainer are required. Refer to instruction
manual supplement D104021X012.
Changing to Reverse Action
1. Bypass the control valve and shut off the input signal line and the supply pressure line to the positioner.
2. Loosen the four thumb screws on the underside of the positioner base and remove the cover.