THE J257 Automatic Refractometer from A.L.P.E . eliminates the expense and contamination associated with using circulating waterbaths to control and maintain the sample temperature.
The J257 utilises state of the art Peltier technology with built-in cooling and heating in both the presser head and surrounding the prism. The J257's two cooling and heating systems, along with a thermally isolated platinum RTD sample temperature sensor, give the J257 accuracy and measurement advantages over other commercially available refractometers which only use the prism to measure and control temperature.
The J257 can control any temperature between 10ºC and 40ºC to better than 0.05ºC. Setting the temperature to 20ºC, 25ºC, 27.5ºC or any temperature within 20ºC of ambient will make the refractometer automatically cool or heat the sample to the set temperature.
The time necessary to reach the set temperature depends upon the original sample temperature and the ambient air temperature. In most situations, set temperature can be obtained in a matter of seconds. As an example, a set temperature of 20ºC will cool a 30ºC sample to 20ºC in twenty seconds. Temperature correction can be used in conjunction with temperature control for a virtually instantaneous measurement.
The J257 Refractometer's large 7.5cm x 10cm cold cathode fluorescent backlit graphics LCD allows the scale, sample temperature, set temperature, air temperature, time, date and temperature correction status to be easily viewed.
All functions are activated through a touchscreen panel which will not wear out or get misplaced like traditional or detachable keypads. The touchscreen is impervious to sharp fingernails, sharp objects, chemicals, and acids.
Operating the J257 can be as simple as placing a sample on the prism, closing the presser and reading the answer- all in a few seconds.
The entire keypad can be "locked out" or just a few keys can be operable, i.e. the measure key, print key, zero key, customer specified sample keys or any combination thereof. The lockout function, like calibration and other functions are all password protected.