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CALIBRATION AND MAINTENANCE GUIDE
VVP10
VALVE POSITIONER
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FUNCTION DETAILS
VVP10 positioner controls the air outlets for the actuator/valve assembly using the nozzle-vane system with magnetic
coil, where the supply pressure passes through an internal pressure regulator, supplying pressure to the coil, which
generates the pilot for controlling a directional spool valve. See the schematic of this system in Figure 1.1, below.
Figure 1.1 – Diagram for pneumatic control.
The regulator for supply pressure (between 20 and 140 psi) limits the pressure in the coil to the range of 18 to 22 psi.
After passing through the nozzle-vane, which contains a magnetic coil and a metallic blade, the pilot pressure varies
between 3 and 12 psi (ideally), for currents in the coil between 0 and 1.6 mA, according to the desired control signal,
modulating the spool valve.
Figure 1.2 – Spool valve positioning.
