HM Digital (DM-1) Residential Inline Dual TDS Meter-Monitor
HM Digital DM-1 Residential Inline Dual TDS Meter
Monitor feed water and product water TDS simultaneously with a dedicated dual-probe meter that installs inline for continuous system performance tracking
Real-time monitoring tells you exactly when filters need service
Dual TDS Display
Separate probes measure incoming tap water and outgoing purified water simultaneously. Compare readings at a glance to verify filter performance without disconnecting anything.
±2% Accuracy
Advanced microprocessor delivers reliable measurements across a 0-9990 ppm range. Factory calibrated with 342 ppm NaCl solution, recalibration possible with mini-screwdriver.
Auto-Off Battery Saver
Two 1.5V button cell batteries provide approximately 1000 hours of continuous use. Unit automatically shuts off after 10 minutes of inactivity to extend battery life.
Inline Installation
Designed for 1/4" OD tubing with 24.5" probe cables for flexible placement. Installs quickly between filter stages or after final membrane. Compact 3 x 0.8 x 1.9 inch housing.
Works with any RO or filtration system using 1/4" tubing
The HM Digital DM-1 meter fits standard 1/4" OD tubing used in most residential reverse osmosis and water filtration systems. Install between pre-filters and membrane, or before and after final polishing stages. Fittings sold separately—use with John Guest or comparable quick-connect fittings for your tubing type. Compatible with all brands including APEC, iSpring, Home Master, Watts, and Pentair systems.
Technical details for the HM Digital DM-1
| Measurement Range | 0-9990 ppm (1 ppm resolution up to 999, 10 ppm resolution above 1000) |
| Accuracy | ±2% full scale |
| Tubing Compatibility | 1/4" OD (fittings not included) |
| Cable Length | 24.5 inches including sensor |
| Power Source | 2 x 1.5V button cell batteries (included) |
| Battery Life | Approximately 1000 hours continuous use |
| Dimensions | 3.0 x 0.8 x 1.9 inches (7.6 x 2 x 4.7 cm) |
| Weight | 2.8 oz (79.4 g) |
| Calibration | Factory calibrated with 342 ppm NaCl, user recalibration available |
Know When to Service
Rising TDS in product water tells you exactly when membranes or filters are exhausted, eliminating guesswork
Verify System Performance
Compare inlet and outlet readings to confirm your RO system is rejecting contaminants as designed
Install and Monitor
Quick inline installation gives customers continuous visibility into their water quality without lab testing
Professional Grade Accuracy
HM Digital microprocessor technology delivers lab-quality measurements in a compact residential package
HM Digital DM-1 Residential Inline Dual TDS Meter
Monitor feed water and product water TDS simultaneously with a dedicated dual-probe meter that installs inline for continuous system performance tracking
Real-time monitoring tells you exactly when filters need service
Dual TDS Display
Separate probes measure incoming tap water and outgoing purified water simultaneously. Compare readings at a glance to verify filter performance without disconnecting anything.
±2% Accuracy
Advanced microprocessor delivers reliable measurements across a 0-9990 ppm range. Factory calibrated with 342 ppm NaCl solution, recalibration possible with mini-screwdriver.
Auto-Off Battery Saver
Two 1.5V button cell batteries provide approximately 1000 hours of continuous use. Unit automatically shuts off after 10 minutes of inactivity to extend battery life.
Inline Installation
Designed for 1/4" OD tubing with 24.5" probe cables for flexible placement. Installs quickly between filter stages or after final membrane. Compact 3 x 0.8 x 1.9 inch housing.
Works with any RO or filtration system using 1/4" tubing
The HM Digital DM-1 meter fits standard 1/4" OD tubing used in most residential reverse osmosis and water filtration systems. Install between pre-filters and membrane, or before and after final polishing stages. Fittings sold separately—use with John Guest or comparable quick-connect fittings for your tubing type. Compatible with all brands including APEC, iSpring, Home Master, Watts, and Pentair systems.
Technical details for the HM Digital DM-1
| Measurement Range | 0-9990 ppm (1 ppm resolution up to 999, 10 ppm resolution above 1000) |
| Accuracy | ±2% full scale |
| Tubing Compatibility | 1/4" OD (fittings not included) |
| Cable Length | 24.5 inches including sensor |
| Power Source | 2 x 1.5V button cell batteries (included) |
| Battery Life | Approximately 1000 hours continuous use |
| Dimensions | 3.0 x 0.8 x 1.9 inches (7.6 x 2 x 4.7 cm) |
| Weight | 2.8 oz (79.4 g) |
| Calibration | Factory calibrated with 342 ppm NaCl, user recalibration available |
Know When to Service
Rising TDS in product water tells you exactly when membranes or filters are exhausted, eliminating guesswork
Verify System Performance
Compare inlet and outlet readings to confirm your RO system is rejecting contaminants as designed
Install and Monitor
Quick inline installation gives customers continuous visibility into their water quality without lab testing
Professional Grade Accuracy
HM Digital microprocessor technology delivers lab-quality measurements in a compact residential package
Original: $45.00
-65%$45.00
$15.75Description
HM Digital DM-1 Residential Inline Dual TDS Meter
Monitor feed water and product water TDS simultaneously with a dedicated dual-probe meter that installs inline for continuous system performance tracking
Real-time monitoring tells you exactly when filters need service
Dual TDS Display
Separate probes measure incoming tap water and outgoing purified water simultaneously. Compare readings at a glance to verify filter performance without disconnecting anything.
±2% Accuracy
Advanced microprocessor delivers reliable measurements across a 0-9990 ppm range. Factory calibrated with 342 ppm NaCl solution, recalibration possible with mini-screwdriver.
Auto-Off Battery Saver
Two 1.5V button cell batteries provide approximately 1000 hours of continuous use. Unit automatically shuts off after 10 minutes of inactivity to extend battery life.
Inline Installation
Designed for 1/4" OD tubing with 24.5" probe cables for flexible placement. Installs quickly between filter stages or after final membrane. Compact 3 x 0.8 x 1.9 inch housing.
Works with any RO or filtration system using 1/4" tubing
The HM Digital DM-1 meter fits standard 1/4" OD tubing used in most residential reverse osmosis and water filtration systems. Install between pre-filters and membrane, or before and after final polishing stages. Fittings sold separately—use with John Guest or comparable quick-connect fittings for your tubing type. Compatible with all brands including APEC, iSpring, Home Master, Watts, and Pentair systems.
Technical details for the HM Digital DM-1
| Measurement Range | 0-9990 ppm (1 ppm resolution up to 999, 10 ppm resolution above 1000) |
| Accuracy | ±2% full scale |
| Tubing Compatibility | 1/4" OD (fittings not included) |
| Cable Length | 24.5 inches including sensor |
| Power Source | 2 x 1.5V button cell batteries (included) |
| Battery Life | Approximately 1000 hours continuous use |
| Dimensions | 3.0 x 0.8 x 1.9 inches (7.6 x 2 x 4.7 cm) |
| Weight | 2.8 oz (79.4 g) |
| Calibration | Factory calibrated with 342 ppm NaCl, user recalibration available |
Know When to Service
Rising TDS in product water tells you exactly when membranes or filters are exhausted, eliminating guesswork
Verify System Performance
Compare inlet and outlet readings to confirm your RO system is rejecting contaminants as designed
Install and Monitor
Quick inline installation gives customers continuous visibility into their water quality without lab testing
Professional Grade Accuracy
HM Digital microprocessor technology delivers lab-quality measurements in a compact residential package
