Hanna HI98703-01 Offers

This meter is supplied complete with AMCO-AEPA-1 primary turbidity standards used for calibration and performance verification. It meets and exceeds the requirements of EPA Method 180.1 and Standard Methods for the Examination of Water and Wastewater 2130 B for turbidity measurements. Users will appreciate the accuracy and sensitivity of this instrument; particularly at very low turbidity levels.

Features

• Multiple reading modes: normal measurement, continuous measurement, or signal averaging measurement are reading modes available
• EPA compliant measurement: when the meter is in EPA mode all turbidity readings are rounded accordingly to meet reporting requirements
• Calibration: A two, three, or four-point turbidity calibration can be performed by using the supplied (<0.10, 15.0, 100, and 750 NTU) standards
• Fast Tracker^™: allows users to record the time and location of a speci˜fic measurement or series of measurements using iButton^® tags near sampling points for quick and easy readings
• GLP data: features complete GLP (Good Laboratory Practice) functions that allow traceability of the calibration conditions. Data includes calibration points, date, and time
• Data logging: up to 200 measurements can be stored in the internal memory and recalled at any time
• Data transfer: for further storage or analysis options, logged data can be downloaded to a Windows compatible PC using the RS232 or USB port and the HI92000 software
• Backlit display: a backlit LCD display provides an easy to understand, user-friendly interface. Displayed codes guide the user step-by-step through routine operation and calibration

Significance of Use

Turbidity is one of the most important parameters used to determine the quality of drinking water. Once considered as a mostly aesthetic characteristic of drinking water, signi˜ficant evidence exists that controlling turbidity is a competent safeguard against pathogens. In natural water, turbidity measurements are taken to gauge general water quality and its compatibility in applications involving aquatic organisms. The monitoring and treatment or wastewater was once solely based on the control of turbidity. Currently, the measurement of turbidity at the end of the wastewater treatment process is necessary to verify that the values are within regulatory standards.

The Requirements of the Nephelometer and Reporting Measurements are:

• The applicable range is 0 to 40 nephelometric turbidity units
• Light source: tungsten lamp operated at a color temperature between 2200-3000°K
• Distance traversed by incident light scattered light within the sample tube: Total not to exceed 10 cm
• Detector: centered at 90° to the incident light path and not to exceed ±30° from 90°, the detector, and filter system if used, shall have a spectral peak response between 400 nm and 600 nm
• The sensitivity of the instrument should permit detection of a turbidity difference of 0.02 NTU or less in waters having turbidities less than 1 unit

Principle of Operation

The light beam that passes through the sample is scattered in all directions. The intensity and pattern of the scattered light is affected by many variables, such as wavelength of the incident light, particle size and shape, refractive index, and color. The optical system of the HI98703 includes a tungsten fi˜lament lamp, a scattered light detector (90°) and a transmitted light detector (180°).

In the ratio turbidimeter range, the microprocessor of the instrument calculates the NTU value from the signals that reach the two detectors by using an eff‰ective algorithm that corrects and compensates for interferences of color. The optical system and measuring technique also compensate for fluctuations in lamp intensity, minimizing the need for frequent calibration.