July 2020
Installation, Operation and Maintenance Manual
MAN 573 Rev. 8
Figure 13
Modulating service
2
P
3
4
5
1
P
Pneumatic
positioner
Pneumatic
control signal
Electric
control signal
Electropneumatic positioner
Pressurized air (supply)
Reduced pressure air
3.2
Residual Risks
When modulating control is required as a function of a pneumatic or electric control signal, a
positioner (5) is used, which controls the supply to the actuator cylinder to keep the valve in the
required angular position. The positioner has a mechanical linkage to the actuator, for a feedback of
the valve position.
3.3
Operations
The operations are carried out sending the proper signal through the control system in compliance
with Customer specifications.
Please refer to applicable “operating diagram” and to Biffi technical documentation supplied.
!
WARNING
The actuator has parts under pressure. Use the due caution. Use individual protections provided for
by the laws and provisions in force.
Operation and Use
16
Section 3: Operation and Use
