Home All HM Digital COM-100 Waterproof EC/TDS And Amp Te...
🚚 Free Shipping $50+
🔒 Secure Checkout
↩️ Easy Returns
Satisfaction Guaranteed

HM Digital COM-100 Waterproof EC/TDS And Amp Temperature Combo Meter

★★★★★
2 Reviews ✓ Verified Buyers
$52.99
$69.99
SAVE 24%
Free shipping to lower 48 states · Tax calculated at checkout
🔥 Loading...
⚠️ Only 3 left in stock — order soon
📦
⚡ Buy it Now

HM Digital COM-100 HMDCOM100 Waterproof EC/TDS And Amp Temperature Combo Meter, 2.1&quot x 2.9&quot x 8.9&quot, White/Purple

  • plastic

  • Imported

  • Measures electrical conductivity (EC), total dissolved solids (TDS), and temperature

  • Four scales: µS, mS, ppm, ppt (mS and ppt are new)

  • Three different nonlinear ECtoTDS conversion factors (KCl, 442TM, NaCl).

  • Waterproof housing (IP67 rating)

  • Measurement Range: 09990 µS; 08560 ppm; 09.99 mS; 08.56 ppt

Product Description

HM Digital's COM-100 is a waterproof combination EC/TDS/Temperature meter that is ideal for all water quality testing, water purification applications, drinking water, wastewater regulation, aquaculture, hydroponics, colloidal silver, labs & scientific testing, pools & spas, ecology testing, boilers & cooling towers, water treatment and more. The COM-100 is a professional level EC/TDS meter at an unbeatable price.

Free shipping on all orders over $50 to the lower 48 states
Ships within 1–2 business days
Easy returns — contact us within 30 days of delivery
Secure checkout with all major cards, PayPal, Shop Pay
HM Digital COM-100 Waterproof EC/TDS And Amp Temperature Combo Meter
HM Digital COM-100 Waterproof EC/TDS And A...
$52.99

Frequently Asked Questions

Is the HM Digital COM-100 really waterproof, and can I use it in saltwater?

Yes, the COM-100 has an IP67 waterproof rating, meaning it can be fully submerged in fresh water temporarily. However, it's not designed for continuous saltwater use; while it can measure saltwater (ppt scale), prolonged saltwater exposure may damage the device over time.

What's the difference between the µS, mS, ppm, and ppt scales on this meter?

µS and mS measure electrical conductivity (EC) at different scales, while ppm and ppt measure total dissolved solids (TDS) in parts per million and parts per thousand respectively. The three conversion factors (KCl, 442TM, NaCl) let you choose the scale most accurate for your specific water type.

How often do I need to calibrate the COM-100, and is it difficult?

The meter should be calibrated before first use and periodically during regular use to maintain accuracy; the exact frequency depends on usage intensity. Calibration requires calibration solutions (sold separately) and is a straightforward process outlined in the manual.

Can I use the HM Digital COM-100 for aquariums, hydroponics, and drinking water quality?

Yes, the COM-100 is versatile and works for aquariums, hydroponics, pools, and general water quality testing since it measures EC, TDS, and temperature across multiple scales. This makes it suitable for both hobby enthusiasts and professionals monitoring various water systems.

How long does the battery last, and what type does the COM-100 use?

The COM-100 uses two 1.5V button cell batteries (typically LR44 or similar), which generally last 1-2 years depending on usage frequency. Battery life is reasonable for occasional to moderate use, though you should keep spare batteries on hand for fieldwork.