6.2
function
Depending on the version, the seat of the valve is closed with or
against the medium flow.
Spring force (CFA) or pneumatic pilot pressure (CFB and CFI) gen-
erates the closing force on the swivel plate. The force is transferred
via a spindle which is connected to the actuator piston.
6.2.1 control functions (cf)
WarninG!
for control function i – danger if pilot pressure fails!
For control function I control and resetting occur pneumatically. If
the pressure fails, no defined position is reached.
▶ To ensure a controlled restart, first pressurise the device with
pilot pressure, then switch on the medium.
control function a (cfa)
Normally closed by spring action
2(A)
1(P)
10
english
Type 2101
Structureandfunction
control function B (cfB)
Normally open by spring action
2(B)
1(P)
control function i (cfi)
Actuating function via reciprocal pressurisation.
2(A)
1(P)