AD31 EC/TDS meter

AD31 EC/TDS meter

ADWA AD31: a pocket digital meter for conductivity (EC), TDS and temperature

The AD31 EC/TDS meter is a pocket digital meter for measuring electrical conductivity (EC) and total dissolved solids (TDS) in water and other liquids. You see the result on the top line of the display and the sample temperature on the bottom line. Automatic temperature compensation adjusts the measurement to temperature, and you switch between EC and TDS modes with one key.

The set includes the AD31 meter, four 1.5 V batteries, a 1.413 mS/cm calibration liquid (20 mL), an electrode rinsing liquid (20 mL) and instructions in Slovenian. The 1382 ppm calibration liquid is not included and is bought separately.

According to the official ADWA manufacturer's instructions it measures EC in the range from 0 to 3999 µS/cm with a resolution of 1 µS/cm, TDS from 0 to 2000 ppm and temperature from 0 to 60 °C.

AD31 EC/TDS meter

How it works and how to calibrate it

Remove the probe cap, switch the meter on, dip the probe into the liquid, stir gently and wait for the value to settle. Switch between EC and TDS with the SET/HOLD key; the same key freezes the display. You can set the TDS factor from 0.45 to 1.00.

Calibration is automatic and single-point. Hold the ON/OFF/MODE key until CAL appears, dip the probe into the 1413 µS/cm calibration solution and wait for the OK message. The CAL symbol means the meter is calibrated. Calibrate when replacing the probe, after measuring aggressive chemicals and whenever you need higher accuracy.

Advantages: AD31 EC/TDS meter

• Pocket meter for EC and TDS in µS/cm and ppm units
• EC 0 to 3999 µS/cm, TDS 0 to 2000 ppm
• Temperature display and automatic temperature compensation
• Switch between EC and TDS with one key
• Automatic single-point calibration
• Adjustable TDS factor and temperature coefficient
• Replaceable probe
• Batteries last about 100 hours of use
• Automatic switch-off after 8 minutes
• Price: €49.90

Use: AD31 EC/TDS meter

Who is it for

Choose it for measuring water, nutrient solutions and other liquids where conductivity is in the range up to 3999 µS/cm. For higher ranges (in mS/cm and ppt) there is the AD32 EC meter, and for professional use the AD-310 EC-TDS meter or the AD330/AD332.

Maintenance: AD31 EC/TDS meter

Storing and cleaning the probe

Rinse the probe thoroughly between consecutive samples to prevent carry-over, and after cleaning rinse it once more with a little of the sample you will measure. Do not touch the probe with your fingers. Calibrate the meter with the 1413 µS/cm solution. A replacement probe is available as the AD31p spare electrode.

Technical specifications: AD31 EC/TDS meter

• EC range: 0 to 3999 µS/cm, resolution 1 µS/cm
• TDS range: 0 to 2000 ppm, TDS factor 0.45 to 1.00
• Accuracy: ±2% of full scale
• Temperature: 0.0 to 60.0 °C, resolution 0.1 °C, accuracy ±0.5 °C
• Temperature compensation: automatic, coefficient β 0.0 to 2.4 %/°C
• Calibration: automatic, 1 point (1413 µS/cm, 1382 ppm or 1500 ppm)
• Power supply: 4 × 1.5 V batteries, about 100 hours
• Dimensions: 175.5 × 39 × 23 mm, weight 100 g
• Automatic switch-off: after 8 minutes

If you are looking for an AD31 EC/TDS meter for quick measurement of water conductivity and TDS, this is a pocket ADWA meter with automatic calibration. Also see all EC and TDS meters.