HI97731 is an advanced portable photometer for the measurement of zinc in water. This meter offers a superior optical system that utilizes a reference detector and narrow band interference filters for extremely fast and repeatable measurements.
No warm up time before taking a measurement
Tutorial mode for step-by-step instructions
CAL Check to verify meter performance
Zinc is normally introduced into drinking water through industrial effluents, especially due to dezincification of brass and deterioration of galvanized iron. In addition to drinking water, zinc is measured in surface finishing, boilers and cooling towers, water conditioning, and effluent waters.
The HI97731 meter measures the zinc content in water samples up to 3.00 mg/L (ppm). The method is adaptation of the Standard Methods for the Examination of Water and Wastewater, 23rd Edition, Zinc on method. When the reagent is added to a sample containing zinc, the sample will turn a brown-green to a blue hue; the greater the concentration, the deeper the color. The associated color change is then colorimetrically analyzed according to the Beer-Lambert Law. This principle states that light is absorbed by a complementary color, and the emitted radiation is dependent upon concentration. For silver determination, a narrow band interference filter at 575 nm allows only yellow-green light to be detected by the silicon photodetector and omits all other visible light emitted from the tungsten lamp. As the change in color of the reacted sample increases, absorbance of the specific wavelength of light also increases, while transmittance decreases.
LED that generates very little heat.
8 nm narrowband interference filter that is accurate to +/- 1 nm.
Reference detector that modulates the voltage to LED for consistent light output.
A concave focusing lens that reduces errors from imperfections in the cuvette.
CAL Check Advanced features including CAL-Check to verify performance and if necessary, recalibrate.
Setup Options Backlit dot matrix LCD that offers an exceptionally intuitive user interface that is easy to read and understand.
Tutorial Mode Tutorial mode for step-by-step instructions to guide a first-time user in how to perform a measurement correctly.
The internal reference system of the HI97731 photometer compensates for any drifts due to power fluctuations or ambient temperature changes. With a stable source of light the readings are fast and stable between your blank (zero) measurement and sample measurement.
High Efficiency Light Source:
LED light sources offer superior performance compared to tungsten lamps. LEDs have a much higher luminous efficiency, providing more light while using less power. They also produce little heat, which could otherwise affect electronic stability.
High Quality Filters:
Improved optical filters ensure greater wavelength accuracy and allow a brighter, stronger signal to be received. The end result is higher measurement stability and less wavelength error.
Greater Light Yield:
A focusing lens collects all of the light that exits the cuvette, eliminating errors from imperfections and scratches that may be present in the glass. The use of the convex lens reduces the need for indexing cuvettes.
CAL Check Functionality:
Hanna’s exclusive CAL Check feature allows for performance verification and calibration of the meter using NIST traceable standards. Our CAL Check standard vials are developed to simulate a specific absorbance value at each wavelength to verify the accuracy of subsequent readings.
Large Cuvette Size:
The sample cell of the HI97731 fits a round, glass cuvette with a 25 mm path length. The relatively long path length of the sample cuvette allows the light to pass through more of the sample solution, ensuring accurate measurements even in low absorbance samples.
Intuitive Dot Matrix Display:
The HI97731 is designed with a backlit, graphic LCD. With virtual keys, a battery status indicator, and error messages. Users will find the meter interface intuitive and easy to read. A dedicated help key provides information relating to the current meter operation, and can be used at any stage in the setup or measurement process to show contextual help.
The meter uses three common AA batteries that allow for about 800 measurements to be taken. The auto-off feature automatically shuts off the meter after 15 minutes of inactivity in order conserve battery life.
0.00 to 3.00 mg/L (as Zn)
±0.03 mg/L ±3% of reading at 25°C
adaptation of Standard Methods for the Examination of Water and Wastewater, 23rd Edition, Zincon method
Photometer/Colorimeter Light Source
LED with 575 nm bandpass filter
Photometer/Colorimeter Light Detector
Bandpass Filter Bandwidth
Bandpass Filter Wavelength Accuracy
round 24.6 mm diameter (22 mm inside)
128 x 64 pixel B/W LCD with backlight
1.5 V AA Alkaline (3 pcs.) / > 800 measurements (without backlight)
after 15 minutes of inactivity (30 minutes before a READ measurement)
0 to 50°C (32 to 122°F); 0 to 100% RH (IP67)
380 g (13.4 oz.)
142.5 x 102.5 x 50.5 mm (5.6 x 4.0 x 2.0")
HI97729C is supplied with CAL Check standards, cuvettes (2), caps (2), plastic inserts for cuvette, (2), scissors, cuvette cleaning cloth, 1.5V AA batteries (3), instruction manual, and instrument quality certificate packaged in a rugged, thermoformed carrying case. HI97729 is supplied with cuvettes (2), caps (2), plastic inserts for cuvettes (2), 1.5V AA batteries (3), instruction manual, and instrument quality certificate.