Cecomp Electronics, APD 3280, Valve Positioner, Potentiometer Feedback, 24 Selectable Input Ranges, 60-300 VDC PowerFeatures:Automatic or Manual Valve ControlTest/Manual Positioning ButtonsInput LoopTracker® LEDRelay Status LEDsHigh Capacity Relay ContactsRemovable Plugs for Faster InstallationInput/Power IsolationPotentiometer, Voltage or mA Feedback ModelsApplications:Valve Position ControllerLinear Actuator ControllerDamper ControllerThe APD 3280 controls the position of a valve or linear actuator by comparing a DC input (control signal) to that of a position feedback potentiometer or slidewire.An SPDT relay provides bi-directional (open-close) signals to drive a motor to open or close a valve. A bi-color LED indicates the Open/Close relay contact status.When the valve position, as indicated by the feedback potentiometer, becomes equal to the position as represented by the control input, the relay will go to the neutral position and the motor will halt.A multi-turn deadband control allows precise tuning of the motor response to eliminate hunting or oscillation.Heavy-duty relay contacts allow the module to directly control high capacity loads as long as the switching current with within the limits shown at left.Auto/Manual SwitchAn Auto/Manual switch allows either closed-loop automatic valve position control or manual positioning via the Open/ Close buttons. The manual mode is useful for troubleshooting, calibration, system testing or as a manual bypass.LoopTrackerA green LoopTracker LED varies in intensity with changes in the control input signal. Monitoring this LED can provide a quick visual picture of your process at all times and save time during initial startup and/or troubleshooting.