The HI96752 portable photometer is for the measurement of calcium and magnesium. Hanna's portable photometers feature an advanced optical system; the combination of a LED light source, a narrow band interference filter, and silicon photodetector ensure accurate photometric readings every time. The Hanna exclusive CAL Check™ feature utilizes ready-made, NIST traceable standards to verify both meter validation and calibration. The exclusive cuvette locking system ensures that the cuvette is inserted into the measurement cell in the same position every time to maintain a consistent path length.
CAL Check™ - Allows for performance verification and calibration of the meter using a CAL Check NIST traceable secondary standard.
GLP - Records the date of the last user calibration performed.
Built in timer - Allows the use of a timer to ensure the appropriate 3 minutes and 30 seconds reaction time is used for the chemical reaction. At the end of the timer countdown the meter will automatically take the reading. This feature ensures consistency across multiple users.
Indexing indent on meter - The meter has an indent that allows for a lock and key fit with the cuvette cap. This ensures that the cuvette is indexed consistently (same position) in order to maintain the same path length for accurate results.
Cooling Lamp Indicator - It is necessary to maintain a consistent temperature of the optical components in order to maintain a narrow wavelength band of light. This photometer has a cooling lamp indicator that is displayed for a short period of time before each measurement in order to allow the components to cool and obtain the highest accuracy possible.
Error messages - Messages on display alerting to problems including no cap, over range and under range readings, and light source error.
Auto-shut off - Automatic shut off after 10 minutes of non-use when the meter is in measurement mode. Prevents wastage of batteries in the event the meter is accidentally not turned off.
Battery status indicator
The instrument has a battery level indicator to display reaming life as follows:
• 3 lines for 100 % capacity
• 2 lines for 66 % capacity
• 1 line for 33 % capacity
• Battery icon blinks when the capacity is less than 10 %.
Units of measure - Appropriate unit of measure is displayed along with reading.
Significance of use
Calcium and magnesium both play important roles in the growth of plants. Calcium helps plant roots develop and increases the resistance and strength of plant tissues and stems. Magnesium is an indispensable mineral that helps in the production of chlorophyll, the light-absorbing green pigment that serves as an energy source for plants. It also increases vitamin concentrations and aids in uptake of phosphorus within the plant body.
The HI96752 offers multiple methods within one meter. Calcium determination uses the oxalate method; magnesium determination uses the calmagite method. The ready made reagents are in liquid form. When the appropriate reagents are added to the sample, a color change will occur due to the presence of calcium or magnesium; 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 determination of both calcium and magnesium, a narrow band interference filter at 466 nm (blue) allows only blue light to be detected by the silicon photodetector and omits all other visible light emitted from the LED. As the change in color of the reacted sample increases, absorbance of the specific wavelength of light also increases, while transmittance decreases.
CAL Check™ standards with certificate
The CAL Check™ standards are used for calibration and performance verification of photometers with the CAL Check™ function. Individual sets of CAL Check™ standards are available for each parameter on the HI96752:
- Calcium: HI96752-11
- Magnesium: HI96754-11
- Lot number
- Expiration date
- Standard value @ 25 °C
- Reference meter NIST traceable
- Light tight
- Protects from accidental breakage
Calcium Range 0 to 400 mg/L Calcium Resolution 1 mg/L Calcium Accuracy ±10 mg/L ±5% of reading at 25°C Calcium Method Adaptation of the Oxalate method. Magnesium Range 0 to 150 mg/L Magnesium Resolution 1 mg/L Magnesium Accuracy ±3 mg/L ±3% of reading at 25°C Magnesium Method Adaptation of the Calmagite method. Photometer/Colorimeter Light Source Light Emitting Diode Photometer/Colorimeter Light Detector Silicon Photocell with narrow band interference filter @ 466 nm Display Liquid Crystal Display (LCD) Battery Type/Life 9V battery Automatic Shut-Off after ten minutes of non-use in measurement mode; after one hour of non-use in calibration mode; with last reading reminder Environment 0 to 50°C (32 to 122°F); RH max 95% non-condensing Weight 360 g (12.7 oz.) Dimensions 192x104x69mm (7.6x4.1x2.7”) Ordering Information HI96752 is supplied with two sample cuvettes with caps, 9V battery, instrument quality certificate, and instruction manual. *CAL Check™ standards and testing reagents sold separately.