26
EB 8310-5 EN
Operation
6 Operation
Crush hazard arising from moving parts.
The actuator contains moving parts (actuator
stem), which can injure hands or fingers if
inserted into the actuator.
−
Do not insert hands or fingers into the yoke
while the valve is in operation.
−
While working on the actuator, disconnect
and lock the pneumatic air supply as well
as the control signal.
Risk of personal injury when the actuator
vents.
Wear eye protection when working in close
proximity to the control valve.
Operating disturbed by a blocked actuator
stem.
Do not impede the movement of the actuator
stem by inserting objects into its path.
6.1 Throttling service
The Types 3271 and Type 3277 Pneumatic
Actuators with 175 and 750 cm² actuator
areas are designed for a maximum supply
pressure of 6 bar when used for throttling
service.
6.2 On/off service
In on/off service, the supply pressure must
be limited depending on the bench range or
operating range of the actuator. The applica-
ble bench range or operating range which
the actuator can move through is written on
the nameplate (see section 3.7).
Actuator stem retracts (FE)
For the direction of action "actuator stem re-
tracts (FE)", the permissible supply pressure
must not exceed the upper bench range val-
ue by more than 3 bar:
Bench range
Fail-safe
action
Max.
supply
pressure
0.2 to 1.0 bar
Actuator stem
retracts
4 bar
0.4 to 2.0 bar
5 bar
0.6 to 3.0 bar
6 bar
Actuator stem extends (FA)
With fail-safe action "actuator stem extends"
and travel stop, the supply pressure must not
exceed the upper spring range value by
more than 1.5 bar.
6.3 Manual mode
In Type 3271 and Type 3277 Pneumatic Ac-
tuators with 750 cm² actuator area and a
handwheel, the upper spring range value
must not exceed 3.1 bar.
WARNING
!
WARNING
!
NOTICE
!
Summary of Contents for 3277
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