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Analytical Quality Assurance

From self monitoring to large laboratory environment
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Spectral and special analysis in industry, education and science and analysis of routine measurements with standard parameters in wastewater and drinking water, as well as environmental analysis and in-the-field use: Spectrophotometers of the photoLab® 6000 series
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Portable Photometers

Environmental Monitoring, water treatment, beverage industry, wine industry, process control, multi-parameter

applications for photometry, pH and turbidity: Portable Photometers of the pHotoFlex® series
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Thermoreactors for COD and all other thermal digestion processes

Thermoreactors are required for the determination of COD, total nitrogen or total phosphorus. In each of the WTW thermoreactors, the most important temperatures and digestion times are stored. They ensure complete digestion of the sample, as they maintain the necessary high reaction temperature throughout the defined period. For sample digestion three crack sets are available: crack set 10 (model 14687, 100 digestions) and crack set 10-C (model 14688, 25 cuvettes) for heavy metal, as well as crack set 20 for total nitrogen (model 14963, 90 determinations).

There are 8, easily selectable digestion programs available. In addition to these 8 fixed standard programs, CR 3200 and CR 4200 thermoreactors allow you to store 8 of your own user-defined programs. Suitable for 16 mm cuvettes.

CR 2200

Ideal for performing routine water analysis tests with small sample amounts, as 8 programs are available for digestion of 12 sample cuvettes at 100, 120, 148 and 150 °C (212, 248 and 298.4 °F).

CR 3200

In addition, you can program the CR 3200 to carry out 8 of your individual digestions at freely selectable temperatures up to 170 °C (338 °F).

CR 4200

The right choice for performing multiple tests simultaneously, such as COD (148 °C/298.4 °F) and total-N (120 °C/248 °F), as the two thermoblocks for 12 cuvettes can each be controlled separately. It also has memory for 8 of your own user-defined programs with free temperature selection up to 170 °C (338 °F).

Model CR 2200 CR 3200 CR 4200
Number of samples, max. 1 x12 2 x 12 same programe 2 x 12, different programs
8 pre-stored programs 100 °C 30 min, 60 min
120 °C mit 30 min, 60 min, 120 min,
148 °C 120 min, 20 min,
150 °C 120 min
100 °C 30 min, 60 min
120 °C mit 30 min, 60 min, 120 min,
148 °C 120 min, 20 min,
150 °C 120 min
100 °C 30 min, 60 min
120 °C mit 30 min, 60 min, 120 min,
148 °C 120 min, 20 min,
150 °C 120 min
User programs 8 freely selectable 25–170°C 8 freely selectable 25–170°C

Temperature Probe TFK CR

Quality Assurance:
Quality assurance is constantly increasing in importance, even in the operational analysis sector. The CR 3200 and CR 4200 thermoreactors are both equipped with the external temperature probe TFK CR (Order No. 250 100) as a testing aid. This temperature probe can be plugged into the interface in place of a cuvette, and the set and actual temperatures can be outputted either to a printer or a PC.
This means that the function can not only be monitored, but also documented.

Fast Digestion for CSB

New programs for COD
For COD digestion, programs according to various international standard methods are available. On demand of many customers, a rapid digestion for 20 minutes at 148 °C (298.4 °F) is provided, as this timespan has proven to be sufficient for many applications.
All reactors have timer functions. All reactors display when the reaction temperature is reached.

Safety precautions
Along with superior safety, all WTW thermoreactors optimize the heat transmission between the heating block and cuvettes. The safety hood prevents chemicals from splashing in the event of a broken cuvette, a covering provides protection from contact with the heating block surface.