S3407BA301N: Flow Rate Output Control with 4-20mA Analog Input Signal or Manual Adjustment. The S420 Series is a variable speed peristaltic metering pumps dose liquid solutions in direct proportion to a 4-20mA analog input signal.  The operator can scale the pump’s response to the signal from 25% to 100% by the potentiometer on the control pad. When operated in the manual mode the maximum flow rate output is adjustable from 5% to 100%. The pump’s ability to accept an incoming 4-20mA analog signal to pace the pump makes the S420 well suited for use with water treatment controls including pH and ORP monitors to maintain proper water chemistry and treatment of effluent discharge water. Common installations include industral and municipal wastewater treatment facilities or municipalities that supply potable water to residential and commercial sites requiring well or surface water treatment.  For the treatment of process water, the S420 can inject solutions such as disinfectants, oxidizing agents, acids, and alkaline.  Please check available chemical resistant charts for compatibility. Accepts 4-20mA analog input signal.