SM-1 or TRM-1 Inline Digital TDS Meter

Compare dissolved-solids readings at one or three points in a compatible water line. The SM-1 and TRM-1 inline meters provide a numerical TDS reference. They are for users checking changes across a filtration or sample system.

• ✅ Choose the monitoring points — Single- and three-channel versions suit different setups.
• ✅ Read the value directly — The digital display presents the result in ppm.
• ✅ Compare system stages — The triple version allows readings at separate line locations.
• ✅ Limit idle power use — Automatic shutoff operates after non-use.

A dissolved-solids comparison across the line

Choose SM-1 for one line point or TRM-1 for three. Confirm the tubing and fitting sizes before installation rather than assuming every connection uses the same thread or diameter.

The confirmed measurement is TDS, not dissolved oxygen, total hardness or a direct safety verdict. Use readings as a comparison within a suitable testing process.

Technical details

• Models: SM-1 or TRM-1
• Channels: 1 or 3
• Range: 0–9990 ppm
• Stated accuracy: ±2%
• Resolution: 1 ppm below 1000, 10 ppm above
• Standard fitting stated: 1/4 inch; confirm selected connection
• Power format: 2 LR44-equivalent 1.5 V cells
• Auto-off: 10 minutes

Choose the channel arrangement for your inline TDS comparison.

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