HM Digital TRM-1: Triple In-Line TDS Monitor

HM Digital TRM-1 is a unique TDS monitoring that offers the user a 3-point contact during the process of filtration. This Triple In-Line TDS monitor allows checking for TDS levels at three points such as with multiple points in an RO system, or DI/RO (deionization / reverse osmosis) and many more.

Price incl. GST

13 in stock

Categories: , SKU: TRM-1


  • Comes with three 1/4-inch T-fittings that are available with 3/8″ or 1/2″ fittings too
  • With Dual Range 0-9990 ppm (From 0 – 999 ppm the resolution is 1 ppm. From 1000 to 9990 ppm, blinking ‘x10’ image indicates that the resolution is 10 ppm.)
  • With microprocessor technology that makes it highly efficient and accurate
  • Three sensing points displays TDS levels with electrode probes
  • Comes with an auto-off function conserves battery power by shutting off automatically after 10 minutes of non-use.
  • TRM-1 is factory calibrate with a 342 ppm NaCl solution. Meters are available for re-calibrating using a mini-screwdriver.

Additional information

Weight 0.23 kg


Weight: 79.4 g (2.8 oz.)

Fittings: 1/4″ standard, also available with 3/8″ or 1/2″

Accuracy: ±2%

Range:  0-9990 ppm

Cable Length: 24.5″ (including sensor)

Conversion Factor: NaCl (avg. 0.5)

UPC: 891144000243

Size: 7.6 x 2 x 4.7 cm (3 x .8 x 1.9 in.)

Battery Life: approx. 1000 hours of continuous use

Power Source: 2 x 1.5V button cell batteries (LR44 or equivalent; included)





  • Window Cleaning/Carwash
  • Drinking Water
  • Food & Beverage
  • Aquaculture
  • Aquarium
  • Water Treatment