Hafner is offering one of the widest ranges of accessories for smart valve automationβcontrolled by an electro-pneumatic positioners. Products include:
Type HVRZN 731 701 function:
5/2-way valve to override a positioner. By switching the hand lever, the actuator can be fully opened or closed.
Type HVRZN 731 702 function:
5/3-way valve to override a positioner. Supply ports from positioner can be cut-off by pulling the knob. By switching the hand lever, the actuator can be fully opened, fully closed or put into intermediate position.
Both hand-lever valves offer a safety lever that needs to be pulled. Unintended actuation is avoided securely.
ΊΪΑΟ³ΤΉΟ pressure switches:Β By turning the hand-wheel the required minimum actuation pressure can be set between 3 and 6 bar.Β If pressure drops below set point, the valve is pneumatically locking the actuator. Actuator remains in current position (Fail-in Place).Β Type P 311 501 SR for single-acting actuators andΒ Type P 411 701 SR for double-acting actuators.
Pressure applied holding valve β pneumatic version (type DSVN 5):Β In case air pressure cuts-off, valve is blocking the actuator. Actuators remains in current position (Fail-in Place).
Pressure applied holding valve βelectro-pneumatic version:Β In the case where air pressure and/or electric signal at the solenoid coil cuts off, the valve is blocking the actuator. Actuator remains in current position (fail-in place).
Hafner Pneumatik
