Ion Selective SensorsTL-HARD-406
Water Hardness Sensor
Ion Selective Sensors
Water Hardness Sensor
TL-HARD-406
PVC membrane ISE hardness sensor. Range 0–1000 mg/L, IP68, RS485 + 4-20mA output.
Request a QuoteProduct Overview
The TL-HARD-406 uses PVC membrane ion-selective electrode technology to measure total water hardness (calcium + magnesium). Suitable for boiler water monitoring, cooling tower control, and water softening system management.
Working Principle
The sensor uses a continuous online measurement principle with automatic temperature compensation. The measurement signal is processed by an integrated microprocessor and transmitted via RS485 Modbus RTU for direct integration with PLCs, data loggers, and SCADA systems. The 4–20 mA analog output provides compatibility with legacy control systems.
Wiring & Signal Output
Power supply: 12–24 V DC (standard); 220 V AC with adapter
Primary output: RS485 Modbus RTU (address configurable 1–247)
Analog output: 4–20 mA (proportional to measured value)
Relay output: 2 × SPDT relay for alarm / dosing control
Communication: Modbus RTU function codes 03 / 06 / 16
Cable entry: M16 cable gland, IP68 submersible cable available
Technical Specifications
| Parameter | Value |
|---|---|
| Measurement Principle | PVC membrane ISE |
| Measuring Range | 0–1000.0 mg/L |
| Accuracy | ±10% FS, ±0.3°C |
| Resolution | 0.1 mg/L |
| Working Conditions | 0–40°C, 0–2 Bar |
| Power Supply | 12–24 VDC |
| Connection | 3/4" NPT Thread |
| Signal Output | RS485 Modbus RTU + 4-20mA |
| Calibration | 2-point calibration |
| Protection | IP68 |
| Cable Length | 5m |
| Material | 316 stainless steel |
Key Features
- PVC membrane ISE for total hardness
- Measures calcium + magnesium combined
- Suitable for boiler and cooling water systems
- Continuous online monitoring
Typical Applications
Boiler water monitoringCooling tower controlWater softening systemsIndustrial process water
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