USFilter Wallace & Tiernan Products announces a new direct mA arrangement of the automatic V-notch positioner used with its gas feed systems and automatic stroke length actuator for its metering pumps. The actuator/positioner accepts a 4-20mA input signal directly from a remote manual control station, SCADA, or other centralized control system. No intermediate controller or signal conditioner is required, reducing costs. In addition, an integral, fixed dosing function provides for direct input from a flow transmitter.
The new direct mA feature is a compact integral design mounted directly into the positioner - no remote "black" box is required. It does not compromise any of the positioner's current features such as the NEMA 4X rating. The dosage rate factor can be set from 10 to 400 percent, using function keys located on the circuit board. For applications where the dosing factor must be changed on a regular basis, an external dosing potentiometer can be used. The mA input control can be retrofit into existing V10k and V2000 gas feeders or Encore(R) 700 and Chemtube(R) 200 and 2000 metering pumps.
Source: USFilter - A Siemens Company