The Model 260 and 260UV Programmable Colorimeters
The basic design of Sherwood Scientific's CHROMA Colorimeters has been stable for several years and they have gained an enviable world-wide reputation for rugged performance.
For the 21st century, Sherwood Scientific updated its Colorimeters and added a software package unique in this class of instrument. The Model 260 Series Colorimeters offer features not elsewhere available and provide solutions to the requirements of quality control, water testing and also the clinical chemist with low sample runs.
Both Models can be powered from a 12V car battery so can be utilised in locations where the power supply cannot always be relied upon.
The CHROMA Model 260 Programmable Colorimeter
The Model 260 replaces the previous CHROMA Model 257 Colorimeter and incorporates full programmability, allowing up to 100 methods to be installed by the operator. This permits semi-automatic operation; the user need only insert the prompted filter. An RS232 output allows the use of a serial printer and every result, blank and calibration is time stamped. The unit allows quick Absorbance and Transmission measurements with Auto-Zero, Concentration with Standard Solutions or Factor, as well as the new Kinetic Reaction Rate and End Point methods.
Temperature and the new CHROMA range
The Model 260 Series Colorimeters have two options to control the temperature of reactions. The low cost option is to use external temperature control by means of solid block heating. The software built in to the 260 Series Models includes the setting of incubation (or lag time) and measuring time. Towards the end of these times, the user is alerted to return the cuvettes containing the blank, sample or calibrant to the Colorimeter by means of a buzzer. The relevant reading is taken and the cuvette is returned to the heating block to complete the rest of the test.
Sherwood Scientific Ltd has also developed an electrically heated cuvette holder (267 86 001), designed specifically for the micro-cuvettes (001 26 120). This is able to maintain the temperature to 37 °C ± 0.1°C and is available as an option with the M260 or as standard with the M260UV.
The CHROMA Model 260UV Programmable Colorimeter
With a working wavelength range spanning 325 to 750 nm, the Model 260UV can be utilised for a wide variety of clinical and non-clinical chemistry tests. The Model 260UV is supplied with a set of eight drop in gelatine filters together with a 340nmm interference filter and a heated cuvette holder for operation at 37°C if necessary. Each unit is thereby supplied capable of performing colorimetric tests across the whole visible wavelength spectrum and in part of the near UV region.
(Shown here with the heated cuvette holder)