The HI96745 portable photometer is for the measurement of pH, total hardness, iron, and free and total chlorine. Hanna's portable photometers feature an advanced optical system; the combination of a special tungsten lamp, 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.
Chlorine and pH are two of the most closely monitored parameters in the analysis of water quality. The disinfecting power of a chlorine solution is pH-dependent; hypochlorous acid (HOCl) is the more effective form of chlorine that is predominant at lower pH levels. As the pH increases, the less effective hypochlorite (OCl-) form becomes more prevalent. Hardness is also an important water quality parameter as it can indicates the presence of magnesium and calcium, which are responsible for scaling of pipes in heating and cooling systems. In domestic water, iron can cause an unpleasant taste, stain laundry, or damage kitchenware; it is also an indicator of ongoing corrosion in piping systems.
The HI96745 offers multiple methods within one meter. pH determination uses the phenol red method; free and total chlorine determination uses an adaptation the Standard Method 4500-Cl G; total hardness determination uses an adaptation of the Standard Methods for the Examination of Water and Wastewater, 18th Edition, colorimetric method; low range iron determination uses an adaptation of the TPTZ method. The reagents are in powder or liquid form depending on the parameter being tested.
When the appropriate reagent is added to the sample, it will display a color change; 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 pH, free and total chlorine, total hardness, and iron, a narrow band interference filter at 525 nm (green) allows only 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.
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 the HI96745:
Supplied with Certificate of Analysis
- pH: HI96710-11
- Free Chlorine: HI96701-11
- Total Chlorine: HI96711-11
- Total Hardness: HI96719-11
- Iron: HI96746-11
Provided storage containers
- Lot number
- Expiration date
- Standard value @ 25°C
- Reference meter NIST traceable
- Light tight
- Protects from accidental breakage
pH Range 6.5 to 8.5 pH pH Resolution 0.1 pH pH Accuracy ±0.1 pH @ 25°C pH Method Phenol red method. The reaction with reagents causes a red tint in the sample. Free Chlorine Range 0.00 to 5.00 mg/L Cl2 Free Chlorine Resolution 0.01 mg/L under 3.50 mg/L; 0.10 mg/L over 3.50 mg/L Free Chlorine Accuracy ±0.03 mg/L ±3% of reading @ 25°C Total Chlorine Range 0.00 to 5.00 mg/L Cl2 Total Chlorine Resolution 0.01 mg/L under 3.50 mg/L; 0.10 mg/L over 3.50 mg/L Total Chlorine Accuracy ±0.03 mg/L ±3% of reading @ 25°C Chlorine Method Adaptation of the USEPA method and Standard 4500-Cl G. The reaction with reagents causes a pink tint in the sample. Hardness, Total Range 0.00 to 4.70 mg/L Hardness, Total Resolution 0.01 mg/L Hardness, Total Accuracy ±0.11 mg/L ±5% of reading @ 25°C Hardness, Total Method Adaptation of the Standard Methods for the Examination of Water and Wastewater, 18th Edition, colorimetric method. The reaction between Mg/Ca and reagents causes a violet tint in the sample. Hardness, Calcium Range 0.00 to 2.70 mg/L Hardness, Calcium Resolution 0.01 mg/L Hardness, Calcium Accuracy ±0.11 mg/L ±5% of reading @ 25°C Hardness, Calcium Method Adaptation of the Standard Methods for the Examination of Water and Wastewater, 18th Edition, colorimetric method. The reaction between Mg/Ca and reagents causes a violet tint in the sample. Hardness, Magnesium Range 0.00 to 2.00 mg/L Hardness, Magnesium Resolution 0.01 mg/L Hardness, Magnesium Accuracy ±0.11 mg/L ±5% of reading @ 25°C Hardness, Magnesium Method Adaptation of the Standard Methods for the Examination of Water and Wastewater, 18th Edition, colorimetric method. The reaction between Mg/Ca and reagents causes a violet tint in the sample. Iron Range 0.00 to 1.60 mg/L Iron Resolution 0.01 mg/L Iron Accuracy ±0.01 mg/L ±8% of reading @ 25°C Iron Method Adaptation of the TPTZ method. The reaction between iron and the reagent causes a violet tint in the sample. Photometer/Colorimeter Light Source Tungsten lamp Photometer/Colorimeter Light Detector Silicon Photocell with narrow band interference filter @ 525 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 HI96745 is supplied with two sample cuvettes with caps, 9V battery, instrument quality certificate, and instruction manual.