Description

The HI96723 portable photometer is for the measurement of chromium VI. 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.

Features at-a-glance

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.

Hexavalent chromium salts are used in various industrial applications, such as in the manufacture of paints, dyes, explosives, and ceramics, and extensively in the metal finishing and plating industries. Due to its toxicity to humans, animals, and aquatic life, hexavalent chromium is actively monitored and neutralized in wastewater from the above industries.

The HI96723 uses an adaptation of the ASTM Manual of Water and Environmental Technology, D1687-92, diphenylcarbohydrazide method to measure chromium VI concentrations of less than 1000 µg/L (ppb). When the diphenylcarbohydrazide reagent is added to samples containing chromium VI, the sample will turn a purple 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 higher levels of chromium VI, 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 HI96723-11 CAL Check™ standards are used for calibration and performance verification of photometers with the CAL Check™ function.

Supplied with Certificate of Analysis

• Lot number
• Expiration date
• Standard value @ 25 ℃
• Reference meter NIST traceable

Provided storage containers

• Light tight
• Protects from accidental breakage