Daruifuno has released the DEC790, a digital conductivity sensor built on a graphite two-electrode measuring cell. The new model combines four selectable conductivity ranges, TDS and salinity measurement, automatic temperature compensation and a native RS485 MODBUS-RTU interface in a single IP68 probe body. The sensor is aimed at municipal water plants, industrial effluent treatment, surface water stations and process water monitoring, where conductivity has to be tracked continuously without a dedicated analyzer cabinet at every point.
Instead of forcing plants to choose between a low range pure water instrument and a wide range process instrument, the DEC790 covers 0~20 µS/cm, 20~200 µS/cm, 200~2000 µS/cm and 2~10 mS/cm in one device. Resolution is 0.01 µS/cm and accuracy is ±1.0% FS. The same probe also reports TDS up to 5 g/L, salinity up to 5 ppt and water temperature from 0.0 to 50.0 °C, which means a single tapping point can supply a complete water quality picture to the control system.
The measuring cell uses two parallel graphite plates rather than polished metal electrodes. Graphite is chemically inert and strongly suppresses the polarization effect that causes metal electrodes to drift in low conductivity water and to foul quickly in dirty water. According to the company, this design choice keeps the zero point stable in pure water rinse applications and extends the practical cleaning interval in wastewater, where oil films and suspended solids normally bias a metal cell within weeks.
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| Parameter | Value |
|---|---|
| Measuring principle | Graphite two-electrode cell |
| Conductivity ranges | 0~20 µS/cm, 20~200 µS/cm, 200~2000 µS/cm, 2~10 mS/cm |
| TDS / salinity | 0~5 g/L / 0~5 ppt |
| Resolution and accuracy | 0.01 µS/cm, ±1.0% FS |
| Protection and pressure | IP68, ≤6 bar |
| Power and output | 9~24 VDC, about 0.2 W, RS485 MODBUS-RTU |
| Body and mounting | PPS, 35 mm diameter, 230 mm length, 1 inch NPT both ends |
The 35 mm body and 1 inch NPT threads at both ends allow the probe to be installed in a pipe tee, a flow-through housing, a submersible bracket or a side wall mount without special adapters. Working pressure is up to 6 bar and the PPS housing is rated IP68 for continuous immersion. A standard 5 metre cable is supplied, with customised lengths available for deep wells, outfalls and floating stations.
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The DEC790 supports deviation correction, factor correction and multi-point calibration with up to five calibration points, using standard solutions of 84, 146, 1413 and 12880 µS/cm. Routine maintenance is limited to a monthly visual inspection and a calibration check, plus cleaning by shaking the probe in clean water or soaking the measuring section in a mild detergent for 15 minutes. The measuring unit is a replaceable module, so a worn cell can be exchanged without replacing the cable, thread or mounting hardware.
The DEC790 is available now in four range configurations with optional cable lengths and OEM labelling for volume projects. Typical applications include sewage treatment plants, drinking water plants, surface water monitoring stations, semiconductor rinse water, mining process water, cooling tower control and aquaculture. Samples and technical documentation, including the Modbus register map, are available on request.
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İlgili kişi: Ms. Yuki Fu
Tel: +8615716217387