S3402BA201N

Precise Chemical Feed That Automatically Follows Process Demand

The Stenner S420 Series was designed for facilities that need chemical feed rates to automatically adjust as operating conditions change. By responding directly to a 4-20mA control signal, the pump increases or decreases output based on real-time input from process control equipment such as pH and ORP controllers.

This capability makes the S420 an excellent choice for water treatment plants, wastewater systems, commercial pools, cooling towers, and industrial processes where maintaining consistent chemical levels is critical. Instead of operating at a fixed feed rate, the pump continuously adjusts to changing system requirements, helping improve dosing accuracy and process control.

The S420 can also be operated manually when needed. Operators can easily adjust output using the control knob, making the pump flexible for start-up, testing, or applications where a control signal is not required.

Beyond automatic control, the S420 includes several features that help protect equipment and reduce downtime. Built-in leak detection monitors the pump head and can stop operation while activating a dedicated output relay if a leak is detected. For critical applications, the backup pump feature allows operation to transfer automatically to a secondary pump if the primary unit experiences a leak, a drive fault, or loss of power.

Key Benefits

, Automatically responds to 4-20mA control signals

, Adjustable scaling from 25% to 100% of maximum output

, Manual operation available

, Backup pump capability

, Leak detection with dedicated relay

, Run verification relay

, Remote start/stop functionality

, LED status indicators for quick diagnostics

, Indoor/outdoor NEMA 4X enclosure

, Continuous-duty brushless DC motor

The S420 also provides the advantages commonly associated with Stenner peristaltic pumps. The pump is self-priming, can run dry without damage, handles off-gassing solutions without losing prime, and features simple tube replacement that can be performed quickly in the field.

Available Models

, S34: Up to 85 GPD

, S44: Up to 150 GPD

, S54: Up to 315 GPD

Performance Highlights

, Up to 315 GPD output

, Up to 100 PSI operating pressure

, 25-foot suction lift

, ±2% reproducibility

, NEMA 4X rated enclosure

, Indoor/outdoor installation

, 2-year warranty

For operators looking for a rugged metering pump that can automatically adjust chemical feed rates based on process conditions, the Stenner S420 Series delivers accurate dosing, advanced protection features, and reliable long-term performance in demanding water treatment and industrial applications.