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HM Digital Com-300 Ph/Tds/EC/Temp Meter

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$115.99
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The new waterproof professional COM-300L pH/EC/TDS/Temperature Meter is the ideal solution for all water quality assessment needs. Its extended design allows all parameters to be measured in large tanks or drums.

The built-in Automatic Temperature Compensation (ATC) sensor ensures accurate temperature measurements.

FEATURES:

- Measurement of hydrogen potential (pH), electrical conductivity (EC), total dissolved solids (TDS), salinity and temperature

- Five scales: pH, µS, mS, ppm 0.5 (NaCl) Scale and 0.7 (442™) Scale

- Automatic Temperature Compensation (ATC) using three temperature coefficients

- Waterproof housing with protection class IP-67

- Digital calibration (button) to any point within the range of the device

- Auto power off, data hold, and low battery indicator function

- Large and easy-to-read LCD with simultaneous temperature display

- Replaceable sensor (model SP-C3)

- Factory calibration (pH/EC/TDS)

- Includes: transparent lid, 2 AAA batteries, pH 4 and 7 calibration solutions, pH solution storage and lanyard

SPECIFICATION:

- pH range: 0 – 14

- EC range: 0 – 9990 µS; 0 – 9.99 mS

- TDS range: 0 – 8560 ppm (0.7 Scale); 0 – 5000 ppm (0.5 Scale)

- Temperature range: 0-55 °C; 32-130°F

- Resolution: 0-99: 0.1 µS/ppm/ 0.01mS; 100-999: 1 µS/ppm; 1000-9990: 10 µS/ppm. Temperature resolution is 0.1 °C/F

- Accuracy: +/- 2%

- EC to TDS conversion factor: Non-linear conversion for KCl, 442TM, or NaCl solutions, user-selectable

- Probe: Removable platinum electrodes and pH glass sensor with support tube electrodes

- Housing: Waterproof (floats) with protection class IP-67

- Power supply: 2 AAA batteries included

- Dimensions: 18.5 x 3.4 x 3.4 cm

- Weight: 164 g

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HM Digital Com-300 Ph/Tds/EC/Temp Meter
HM Digital Com-300 Ph/Tds/EC/Temp Meter
$115.99

Frequently Asked Questions

How do I calibrate the HM Digital COM-300 pH/TDS/EC meter?

The COM-300 uses two-point calibration for pH and single-point calibration for EC/TDS. Simply use calibration solutions (pH 7.0 and 4.0 for pH, or 1413 µS/cm for EC) and follow the calibration mode instructions in the manual—most users complete calibration in under 5 minutes.

Is the COM-300 waterproof, and can I use it to test water in large tanks or drums?

Yes, the COM-300 is fully waterproof with an extended probe design specifically made for testing large tanks and drums without having to pour water into a separate container. The extended length allows you to reach deep into storage tanks for accurate readings.

What does the Automatic Temperature Compensation (ATC) on the COM-300 do?

The built-in ATC sensor automatically adjusts pH and EC/TDS readings based on water temperature, ensuring accurate measurements across different temperature ranges without manual correction. This is especially useful since water quality parameters can fluctuate with temperature changes.

How long do the batteries last in the HM Digital COM-300?

The COM-300 uses two CR2032 batteries that typically last 1-2 years with regular daily use, though this depends on frequency of testing and continuous monitoring. Battery life is sufficient for most home water quality testing needs.

Can the COM-300 meter be used for aquarium, hydroponics, and pool water testing?

Yes, the COM-300 is ideal for aquariums, hydroponic systems, and pools since it measures pH, EC, TDS, and temperature—all critical parameters for these applications. The waterproof design and extended probe make it practical for frequent testing across different water systems.