SUMMARY
This compact electrical conductivity meter measures electrical conductivity from a sample volume of only 0.12 mL by applying the sample directly to its flat sensor.
It also provides convenient Total Dissolved Solids (TDS) conversion and enables quick, reliable measurement in a compact, portable format.
It is useful for testing rainwater, rivers, lakes, aquarium water, soil extracts, hydroponic nutrient solutions, and agricultural salt conditions.
FEATURES
- Measures electrical conductivity from only 0.12 mL of sample
- Wide EC measurement range from 0 to 199.9 mS/cm
- TDS conversion display from 0.0 to 9900 ppm
- Automatic measurement-range switching
- Up to three calibration points
- Automatic recognition of 1.41, 12.9, and 111.8 mS/cm standard solutions
- Automatic temperature compensation
- Temperature conversion to 25°C with a fixed coefficient of 2%
- Temperature sensor adjustment function
- Auto Hold function
- Auto Stability function
- Selectable TDS conversion modes and factors
- Backlit monochrome digital LCD
- Automatic power-off after 30 minutes
- Remaining battery level display
- IP67 water-resistant construction
- Replaceable sensor
- Portable storage case and measurement accessories included
VERSATILE SAMPLING METHODS
LAQUAtwin's flat-sensor design allows samples to be applied or collected in several convenient ways. Choose the method that suits the sample and measurement purpose.
Direct Drop Measurement
Apply a liquid sample directly to the flat sensor with a dropper, syringe, or pipette. The EC-33B requires only 0.12 mL or more for measurement.
Immersion Measurement
For liquid samples in a beaker or container, the sensor can be immersed directly in the sample. Open the sliding cap on the sensor guard before measurement.
Scoop Sampling
The sensor guard can be used to scoop a liquid sample directly from rainwater, a river, lake, aquarium, tank, nutrient solution, or other sampling location for convenient on-site measurement.
Moist Solid Samples
Moist solid samples such as foods or plant materials can be cut into small pieces and placed on the flat sensor when sufficient liquid makes contact with the electrode.
Powder Samples
Place the powder sample on the flat sensor and add a fixed amount of pure water before measurement. Keep the sample and water quantities consistent when comparing results.
Paper, Textiles, and Sheet-like Samples
Cut the sample into small pieces, place them on the flat sensor, and add a fixed amount of pure water to measure soluble components extracted from the material.
SPECIFICATIONS
| Model | LAQUAtwin-EC-33B |
|---|---|
| Measurement Principle | Two-electrode bipolar AC method |
| Required Sample Volume | 0.12 mL or more |
| Measurement Range |
Electrical conductivity: 0 to 199.9 mS/cm Electrical conductivity: 0 to 19.9 S/m TDS conversion: 0.0 to 9900 ppm |
| Resolution |
0 to 199 μS/cm: 1 μS/cm 200 to 1999 μS/cm: 1 μS/cm 2.00 to 19.99 mS/cm: 0.01 mS/cm 20.0 to 199.9 mS/cm: 0.1 mS/cm |
| Temperature Display Range / Resolution | 0 to 50°C / 0.1°C |
| Calibration | Up to 3 points*1 |
| Accuracy |
Measurement ranges 1 to 3: ±2% F.S. Measurement range 4: ±5% F.S.*2 |
| Main Functions |
Automatic measurement-range switching Automatic standard solution recognition Temperature conversion to 25°C with a fixed coefficient of 2% Temperature sensor adjustment function Auto Hold Auto Stability function Automatic power-off after 30 minutes Remaining battery level display Replaceable sensor TDS conversion: Factor 0.4 to 1.0, 442, NaCl, and EN27888 Automatic temperature compensation |
| Water Resistance | IP67*3 |
| Display | Custom monochrome digital LCD with backlight |
| Operating Environment | 5 to 40°C, 85% relative humidity or less, non-condensing |
| Power Supply | Two 3 V CR2032 coin-type lithium batteries |
| Battery Life | Approximately 400 hours of continuous use with the backlight switched off*4 |
| Main Material | ABS resin |
| Dimensions and Weight |
W164 × H29 × D20 mm, excluding protruding parts Approximately 50 g, excluding batteries |
| Included Accessories |
Conductivity sensor Two CR2032 coin-type lithium batteries One dropper Instruction manual Quick manual Storage case 1.41 mS/cm conductivity standard solution, 14 mL × 1 bottle*5 Conditioning solution, 14 mL × 1 bottle |
| Main Consumables |
S070: Conductivity sensor 514-20: Conditioning solution 514-22: 1.41 mS/cm conductivity standard solution 514-23: 12.9 mS/cm conductivity standard solution |
*1 The meter automatically recognizes 1.41 mS/cm, 12.9 mS/cm, and 111.8 mS/cm standard solutions.
*2 Indicates repeatability when the same standard solution is measured after calibration with that standard solution. Error in the standard solution and rounding error of ±1 digit are not included.
*3 Equivalent to IP67. The meter will not fail after immersion in water at a depth of 1 m for 30 minutes. It cannot be used underwater.
*4 Battery life is reduced to approximately one-third when the backlight is used. The backlight remains illuminated for approximately 20 seconds.
*5 The 12.9 mS/cm standard solution required for two-point calibration is sold separately. For three-point calibration, prepare a 1 mol/L potassium chloride aqueous solution.
TDS Conversion Notes
The TDS value is calculated from the measured electrical conductivity using the selected conversion setting. It is not a direct measurement of the dry mass of dissolved solids.
Available conversion settings include a user-selectable factor from 0.4 to 1.0, as well as 442, NaCl, and EN27888 modes.
When comparing TDS results, use the same conversion setting, temperature conditions, and sample preparation method.






