Hanna Instruments Taiwan
The Hanna Advantage: A Worldwide Leader in Technology and Innovation 100% Quality  360 Value
Contact Hanna: +886-2-8797-2918
Hanna Instruments Worldwide
Customer Support: +1 (800) 426-6287

Portable High Range EC/TDS Meter - HI99301

The HI99301 is a rugged, portable EC/TDS and temperature meter housed in a case rated for IP67 conditions. It is supplied with a two-ting conductivity probe to allow for high range EC measurements from 0.00 to 20.00 mS/cm and TDS measurements from 0.00 to 10.00 ppt. All readings are adjusted with Automatic Temperature Compensation (ATC) and users are able to adjust the temperature correction coefficient and TDS factor for accurately compensated measurements.

  • One-point Automatic Calibration
  • Adjustable TDS factor
  • Automatic Temperature Compensation


The portable, waterproof HI99301 EC/TDS and temperature meter is suitable for use in applications as diverse as wastewater treatment, reverse osmosis, and HVAC. It measures high range conductivity in mS/cm and TDS in ppt. The HI763063 EC/TDS probe is a twO-ring sensor that resists clogging and is easy to clean. The probe also features a built-in temperature sensor to allow for Automatic Temperature Compensation from 0 to 60℃ (32 to 140℉).

The meter easily fits in the palm of your hand and the bottom probe connection ensures the electrode cable doesn’t get in the way. The large, multi-level LCD displays the primary reading, temperature, and calibration guides simultaneously. Symbols and messages on the LCD indicate meter status and guides users through operations.

Features at-a-glance

Two-Ring Probe – The HI763063 is a two-pole probe that comes with the HI99301, offering an accurate solution for high range EC and TDS readings. The probe features a built-in temperature probe to allow for temperature compensated readings.

Two Measurement Modes – HI99301 offers two measurement modes: EC and TDS. Users can easily switch between measurement modes with a simple press of the MODE button. EC measurements range from 0.00 to 20.00 mS/cm; TDS measurements range from 0.00 to 10.00 ppt.

Adjustable TDS Factor – The TDS value in aqueous solutions is directly proportional to conductivity. The ratio between the two parameters depends on the solution being measured. The HI99301 has an adjustable TDS factor from 0.45 to 1.00 with 0.01 intervals, allowing users to choose the conversion factor that is the most appropriate for their particular solution.

Automatic Temperature Compensation – Since temperature has such a dramatic effect on conductivity and TDS readings, having a meter that offers temperature compensated readings is invaluable. The probe of the HI99301 features a built-in temperature sensor that automatically accounts for the effects of temperature in the range of 0 to 60℃ (32 to 140℉).

Adjustable Temperature Compensation Coefficient – The temperature compensation coefficient, also known as β, is adjustable from 0.0 to 2.4%/℃ with 0.1% intervals; this factor corrects the reading a set percentage % for each degree Celsius change in the sample.

Automatic Calibration – The HI99301 can be automatically calibrated at one point in a standard EC or TDS solution. A 12.88 mS/cm standard is used for EC calibration, which will automatically calibrate TDS readings. However, if the meter is in TDS mode and set to 0.5 conversion factor, a direct calibration in 6.44 ppt TDS calibration solution can be used.

Battery Error Prevention System (BEPS) – The Battery Error Prevention System detects when the batteries become too weak to ensure reliable measurements.

Instability Indicator – The HI99301 displays a clock tag that will disappear when a reading has achieved stability.

Additional information

Weight 1.02 kg


EC Accuracy

±2% FS

EC Calibration

automatic, single point at 12.88 mS/cm

EC Range

0.00 to 20.00 mS/cm

EC Resolution

0.01 mS/cm

TDS Accuracy

±2% f.s.

TDS Calibration


TDS Range

0.00 to 10.00 ppt (g/L)

TDS Resolution

0.01 ppt (g/L)

Temperature Accuracy

±0.5°C /±1°F

Temperature Range

‐5.0 to 105.0 °C / 23.0 to 221.0 °F


SKU HI99301
Name Portable High Range EC/TDS Meter – HI99301
EC Range 0.00 to 20.00 mS/cm
EC Resolution 0.01 mS/cm
EC Accuracy ±2% FS
EC Calibration automatic, single point at 12.88 mS/cm
TDS Range 0.00 to 10.00 ppt (g/L)
TDS Resolution 0.01 ppt (g/L)
TDS Accuracy ±2% F.S.
TDS Calibration automatic
EC/TDS Temperature Compensation automatic, 0 to 60°C (32 to 140°F)
Temperature Correction Coefficient automatic, with b selectable from 0.0 to 2.4 %/ °C in 0.1 increments
EC to TDS Conversion Factor Selectable from 0.45 to 1.00 (CONV) in 0.01 increments
Temperature Range ‐5.0 to 105.0 °C / 23.0 to 221.0 °F
Temperature Resolution 0.1°C / 0.1°F
Temperature Accuracy ±0.5°C /±1°F
EC/TDS Probe HI763063 with built-in temperature sensor, quick connect DIN connector and 1 m cable (included)
Automatic Shut-Off user selectable: after 8 min, 60 min or disabled
Battery Type/Life 1.5V AAA (3) / approximately 500 hours of continuous use
IP Protection IP67
Environment 0 to 50°C (32 to 122°F); RH 100%
Dimensions 154 x 63 x 30 mm (6.1 x 2.5 x 1.2”)
Weight 196 g (6.91 oz.)

Ordering Info

HI99301 is supplied with HI763063 EC/TDS probe, HI70030 12880 µS/cm calibration solution sachet (1), HI70038 6.44 ppt calibration solution sachet (1), batteries, calibration certificates for both meter and probe, instruction manual, and rugged thermoformed carrying case.


Portable High Range EC/TDS Meter – HI99301