6
EB 8392 EN
Design and principle of operation
3
Design and principle of oper-
ation
The reversing amplifier allows double-acting
pneumatic actuators to be operated using
single-acting positioners or limit switches.
The positioner creates an output signal pres
-
sure Y
1
, to which the air pressure Y
2
is add
-
ed. The reversing amplifier uses the supply
pressure Z as auxiliary power.
The following rule applies:
Y
1
+ Y
2
= Z
Example:
Y
1
of the positioner
1 bar
Supply pressure Z
6 bar
Resulting Y
2
5 bar
Z
Y
2
Y
1
Z
Y
1
Output 38
Supply
9
Positioner
Pressure is added to Y
1
to create 6 bar
Vent plug (IP 65)
Chamber 1
Chamber 2
Reversing amplifier
Supply air (max. 6 bar)
Pneumatic rotary
actuator (double-
acting)
C
Supply air
Y
1
Output signal pressure
Y
2
Resulting (opposing) signal pressure
1)
Air chamber 1 opens the valve when the pressure rises
2)
Air chamber 2 closes the valve when the pressure rises
1)
2)
Fig. 1:
Schematic diagram of Type 3710 Reversing Amplifier