Renke RS-CL-N01-3-20-EX Residual Chlorine Sensor, 0-20 mg/L, RS485/4-20mA/0-10V Output, 3/4" Thread

The sensor provides dual output capabilities. It features a digital RS485 interface using the Modbus RTU protocol for network integration, alongside a user-selectable analog output. You can configure the analog output as either a 4–20mA current loop, a 0–5V signal, or a 0–10V signal to match your PLC, data logger, or controller input requirements.

No, this sensor operates on a reagent-free, non-membrane principle. It uses a constant voltage method with a high-purity platinum electrode, eliminating the need for consumable reagents or permeable membranes. This design significantly reduces long-term maintenance costs and operational complexity while ensuring stable performance.

For optimal performance and accurate readings, the sensor requires a consistent sample flow past the electrode within a range of 10 to 30 cm³ per second. This flow rate ensures proper electrolyte refreshment at the sensing surface. Installation should include appropriate piping and flow control to maintain this range.

Connect the sensor's RS485 wires (typically A, B, and ground) to your host device (PLC, PC with USB converter, or data acquisition module) using a standard twisted-pair cable. The sensor communicates via the Modbus RTU protocol. You will need to use Modbus-compatible software or code to read the measured chlorine value and other parameters from its predefined register map.

Yes. The sensor ships with a standard 5-meter cable. For RS485 communication, the cable can be extended up to 20 meters (or further with proper termination and signal conditioning) without significant signal degradation. For analog outputs, longer runs are possible, but for 4–20mA, ensure your power supply can handle the loop resistance over the extended distance.