China TDS EC Meter Wholesaler & Manufacturer

Theoretical Foundations of EC to TDS

Electrical Conductivity (EC) quantifies the capacity of aqueous media to conduct galvanic current, measured in microSiemens per centimeter (µS/cm) or milliSiemens (mS/cm). Total Dissolved Solids (TDS), expressed in milligrams per liter (mg/L) or parts per million (ppm), represents the cumulative mass of mobile charged mineral cations and anions.

Because EC measures ionic mobility while TDS measures dry mass, standard portable meters rely on an empirical linear multiplier (k-factor):

• TDS (ppm) = EC (µS/cm) × k-Factor (typically 0.50 to 0.70)
• Drinking Water / Potable Networks: 0.50 – 0.55 (NaCl standard)
• Hydroponic Nutrient Solutions: 0.64 – 0.65 (442 standard)
• Brackish Streams & Heavy Sludges: 0.70 – 0.85 (Sulfate standard)

Electrode vs. Toroidal Induction

Selecting appropriate conductivity cell physics determines field longevity, maintenance overhead, and measurement integrity across varying salinity regimes:

• 2-Electrode Conductive Cells: Ideal for ultrapure water (UPW), boiler condensate, and reverse osmosis permeate (<20 µS/cm). High sensitivity, prone to electrode polarization at high salinity.
• 4-Electrode Alternating Cells: Minimizes cable resistance and boundary polarization. Optimal for medium brackish streams and agricultural nutrient monitoring.
• Toroidal / Inductive Sensors: Completely non-contact magnetic coil excitation. Unaffected by biofouling, oil deposition, or severe mineralization up to 2,000 mS/cm.

Advanced Thermal Compensation (ATC)

Liquid conductivity exhibits significant positive thermal dependency, shifting by roughly 1.8% to 2.5% per degree Celsius as fluid viscosity changes and ion dissociation rates accelerate.

BOQU industrial transmitters integrate programmable multi-slope algorithms:

• Standard Linear Slope: User-calibrated 0.00% to 10.00%/°C referenced to standard 25°C baseline.
• Non-Linear Matrix (DIN EN 27888): Essential for natural surface waters, municipal groundwater, and effluent monitoring.
• High-Purity Neutralization Curves: Specialized compensation for power station trace demineralization and semiconductor rinsing.

Semiconductor RO & UPW Lines

Deployment: Microelectronics cleanrooms across East Asia.

Challenge: Maintaining ultra-low ionic drift below 0.055 µS/cm (18.2 MΩ·cm resistivity) in continuous deionized polishing loops.

BOQU Solution: High-precision 316L stainless steel two-pole cells coupled with sub-microSiemens digital transmitters featuring dynamic temperature slope compensation.

Thermal Power & SWAS Loops

Deployment: Supercritical thermal boilers in Northern China and Europe.

Challenge: Preventing caustic gouging, silica volatility, and catastrophic tube embrittlement at trace ionic thresholds.

BOQU Solution: Integrated Steam and Water Analysis Systems (SWAS) monitoring specific, cation, and degassed cation conductivity alongside silica/sodium trace analyzers.

Commercial Recirculating Aquaculture (RAS)

Deployment: Intensive marine hatchery loops across Korea & Southeast Asia.

Challenge: Sudden feed mineralization and salinity shifts causing lethal osmotic stress and catastrophic biomass loss.

BOQU Solution: IOT-485 digital conductivity and optical dissolved oxygen arrays feeding directly into PLCs to govern automated seawater blowdown and oxygenation.

Automated Dairy & Beverage CIP Systems

Deployment: Multi-line dairy and brewery packaging facilities.

Challenge: Distinguishing residual chemical rinse waters from caustic sanitization streams to avoid product contamination and waste.

BOQU Solution: SJG-2083CS toroidal inductive sensors providing rapid milli-second detection of phase transitions between water, caustic soda (NaOH), and nitric acid.