HI-97790 Total and Free Chlorine Portable Photometer

The HI-97790 Total and Free Chlorine Photometer offers an efficient, accurate way to measure two of the most vital water parameters for the water utility, drinking water and wastewater industries. This portable meter has a built-in successive process for the measurement of free chlorine followed by total chlorine, requiring a single sample to complete both measurements for efficiency in testing.

This portable water meter is an ideal solution for regulatory and compliance requirements where successive sample measurements are necessary. The HI-97790 can be carried anywhere on-site and in the field for measurement, with a positive-locking system that ensures vials are placed in the same position with each measurement, providing consistency and reliability in testing.

The method is an adaptation of the Standard Methods, 4500‐Cl G, DPD Colorimetric Method. 

HI-97790 Features

One sample, two measurements

The HI-97790 allows you to perform successive measurements of free and total chlorine using a single sample. This saves time and improves efficiency in testing while meeting regulatory compliance where measurement of both using a singular sample is required. These are the steps to measure free and total chlorine with this compact portable photometer:

1. Take a zero reading
2. Add required reagents for free chlorine measurement
3. Read the results of testing
4. Add required reagents for total chlorine measurement
5. Read the results of testing
6. Dispose of your sample

Measure anywhere

The portable design of the HI-97790 allows this water photometer to be utilised in a wide range of environments where free and total chlorine measurements are required. The photometer uses AA batteries, with no requirement for connection to power to complete measurement. A built-in battery status indicator provides clear information about the remaining battery life, with auto shut-off to prevent battery wastage.

Designed for ease of use

The HI-97790 Free and Total Chlorine Photometer includes multiple features for ease of use when measuring. Auto data log records the results of testing, with the ability to recall up to 50 individual measurements from the meter for immediate comparison. The unit of measurement is displayed on the screen with the reading, and a robust error system prevents incorrect measurement due to no cap, high zero and standard too low.

On-screen tutorial mode

A complete on-screen tutorial provides step-by-step instructions for the measurement process, making it easy to accurately and consistently test water samples. This tutorial can be used at any time and is easily accessible on the photometer, with no additional software or connection required.

Advanced optical design

The HI-97790 features an advanced LED optical system that utilises a reference detector and a focusing lens to eliminate errors typically caused by changes in light source or imperfections within glass vials. The use of LEDs provides more light while reducing the amount of power required for each test and emits little heat to ensure long-term electronic stability.

The system is sealed to prevent dust, dirt or water from entering. A positive-locking system for the inserted vials ensures they are placed in the same position each time for consistently accurate measurement in combination with the LED optical system.

Built-in timer

This photometer for chlorine includes a built-in reaction timer, helping to ensure consistency between both individual and successive tests. The timer is displayed clearly on the screen, providing feedback during the testing process.

Cal Check included

Validate the performance of the HI-97790 at any time with Cal Check vials made with NIST traceable standards. The Cal Check screen provides clear step-by-step instructions for the validation process and user calibration, for peace of mind during measurement.

Floating case for easy retrieval

The HI-97790 features a waterproof IP67-rated case, ensuring this instrument can continue operation after it is dropped in water. This meter also floats on the surface, allowing for easy retrieval in the field. The robust design of this meter makes it suitable for measurement in a wide range of environments.

FAQs

What industries is the HI-97790 suitable for?

The HI-97790 chlorine water photometer is suitable for a range of different industries. The primary applications for this meter include drinking water and wastewater measurement. This compact meter is also suitable for the measurement of free and total chlorine in swimming pools and hot tubs.

Can this chlorine meter measure both types of chlorine?

This compact portable photometer measures both free and total chlorine. Only a single sample is needed to measure both parameters in succession, providing an easy and efficient method to determine both the free and total chlorine levels within your sample.

Can you access data directly on the HI-97790?

Automatic logging functionality stores data directly in the HI-97790 meter for ease of access. Once data has been logged, up to 50 individual measurements can be recalled using the menu on the meter, enabling access to earlier information for recording and comparison.

Which reagents do I need for the HI-97790?

This chlorine photometer is compatible with the following reagents:

• HI-93701-F free chlorine liquid reagent for 300 tests
• HI-93701-T total chlorine liquid reagent for 300 tests

Chlorine (all methods)
Range	0.00 to 5.00 mg/L (as Cl₂)
Resolution	0.01 mg/L
Accuracy	±0.03 mg/L ±3% of reading at 25 °C
Method	Adaptation of Standard Methods, 4500-Cl G, DPD Colorimetric Method
Measurement system
Light source	Light emitting diode
Bandpass filter	525 nm
Bandpass filter bandwidth	8 nm
Bandpass filter wavelength accuracy	±1.0 nm
Light Detector	Silicon photocell
Cuvette type	Round 24.6 mm diameter (22 mm inside)
Additional specifications
Auto logging	50 readings
Display	128 x 64 pixel B/W LCD with backlight
Auto-off	After 15 minutes of inactivity ((30 minutes before a Free Cl2 / Total Cl2 measurement)
Battery type	Alkaline 1.5 V AA (3)
Battery Life	above 800 measurements (without backlight)
Environment	0 to 50 °C (32 to 122 °F); 0 to 100% RH, non-serviceable
Dimensions	142.5 x 102.5 x 50.5 mm (5.6 x 4.0 x 2.0")
Weight	380 g (13.4 oz.); with batteries
Casing	IP67, floating case
Additional information:	HI-97790 is supplied with sample cuvette (2 pcs.); sample cuvette cap (2 pcs.); plastic stopper (2 pcs.); 1.5V AA alkaline battery (3 pcs.); quick reference guide with instructions for manual download and instrument quality certificate. CAL Check standards and testing reagents sold separately.