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Evolution-RO™ TDS Pro in/out PPM Monitor: ½" Inlet x ⅜" Outlet

    • Measures unpurified water PPM going in to reverse osmosis system and purified water PPM coming out
    • Monitors the performance of your RO system
    • Instantly displays values and allows you to switch back and forth between dirty and clean water TDS
    • Indicates when it’s time to change the RO membranes
    • Pro model features larger, more water resistant display and shielded cables
    • ½" inlet and ⅜" outlet designed to be used with the Evolution-RO
    • Dimensions (H x W x D): 2.625" x 4.75" x 1.375" body only
    • Weight: 0.5781 lbs total
    • Tariff: 8421990010


    Your monitor was factory calibrated to 342 ppm (NaCl). This level is suitable for most tap water/filtered water applications, so it is ready to use out of the box. However, you may need to re-calibrate based on you needs, as well as from time-to-time to ensure best results.

    To Calibrate

    1. Obtain a certified calibration solution that is correct for your needs. The calibration solution should be NaCl (sodium chloride). HM Digital’s 342 ppm NaCl solution is recommended.
    2. Disconnect both T-fittings from their tubes. Do not remove the sensor from the T. Ensure the orientation of the sensor to the fitting is correct. Shake any water out.
    3. For better accuracy, calibrate to a flowing solution. If this is not possible, you can calibrate to a still solution. (If calibrating to a still [not flowing] solution, calibrate to 3% above the level of the calibration solution. This will accommodate for the lack of flowing water, which the monitor is programmed for. For example, if the calibration solution is 342 ppm, calibrate to 352 ppm.)
    4. Turn on the monitor and place each T-fitting (with the sensors in them) into the calibration solution. You will get a reading. Ensure the fitting is completely filled with solution and there are no air bubbles. This step is critical for proper calibration. If the reading is correct, stop here.
    5. If the reading on the monitor (for either line) does not match the solution, select the line you wish to calibrate (they are calibrated separately) by clicking IN or OUT.
    6. Press and hold the IN or OUT button (the side you want to calibrate) for 2 seconds. “CAL” will flash on the screen and the corresponding green light will blink.
    7. Press the up button (IN) or the down button (OUT) to adjust the reading until it matches the value of your calibration solution. Hold for rapid advancement. Do not move the sensor!
    8. Once the reading is correct, press the POWER button once. Wait until “End” appears. This sensor is now calibrated and will revert to the measurement reading. Each sensor needs to be calibrated separately.

    To cancel calibration, press POWER twice.

  • TDS Pro: in/out PPM Monitor with ½" Inlet x ⅜" Outlet Downloads


Part Number: HL 28010
UPC: 812111010812

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