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HM Digital

HM Digital DM-3 Commercial In-Line Dual TDS Meter

Part Number: DM-3-NF

Elevate the performance of your water filtration system with the DM-3, a commercial-grade EC/TDS monitor engineered for precision and reliability. Designed to measure the Electrical Conductivity (EC) and Total Dissolved Solids (TDS) of both feed (input) and product (output) water, the DM-3 ensures you have real-time data to maintain optimal water quality.

The DM-3 boasts a large, backlit screen for clear visibility, even in dark environments, and is equipped with robust shielded cables and diagnostic messaging, making it the ideal choice for Reverse Osmosis (RO) and Deionized water (DI) filtration systems. It excels in a variety of applications, including drinking water, water treatment, aquariums, hydroponics, and more.


- Advanced Microprocessor Technology:** Highly efficient and accurate measurements.
- Dual Probe Readings:** Displays TDS levels for both feed and product water.
- Auto-Off Function:** Automatically shuts off after 3 minutes to conserve battery power.
- Factory Calibrated:** Pre-calibrated with a 342 ppm NaCl solution, featuring digital calibration.
- Diagnostic Error Messaging:** Helps identify and troubleshoot issues quickly.
- Shielded Sensor Cables:** Provides durability and interference protection.

Upgrades from DM-1 & DM-2

- Commercial/Industrial Design:** Enhanced for tougher applications.
- Water-Resistant Casing:** Provides additional protection.
- Individual Line Calibration:** Digital calibration for each line.
- Improved Display:** Extra-large, easy-to-read LCD.
- Longer Cables:** Waterproof, shielded for greater durability.
- Slim Design:** New, sleek profile with variable mounting options.

The DM-3 is your go-to solution for professional-grade water quality monitoring, offering superior accuracy, reliability, and ease of use for a wide range of applications. Whether for industrial water treatment or hobbyist setups, the DM-3 delivers unmatched performance.

California residents Prop 65 Warning
This product contains materials known to the State of California to cause cancer and birth defects or other reproductive harm. www.p65warnings.ca.gov