6SYSTEM MODEWhen the instrument is first used, the SYSTEM mode should be used to setthe preferred operating options:• Use the and keys to scroll through the features.• Use the and keys to select the options.• Press [OK] to accept the selections and return to PHOTOMETER mode.Back LightThe graphic display features a backlight to enhance the display contrast. Thismay be switched off to conserve battery power.Language OptionsThe photometer can be operated in a number of different languages. When aparticular language is selected, the test names and operating commands willappear in that language. Certain tests and unit options are provided inaccordance with the conventions of particular countries and are only availablewhen the photometer is switched to the language concerned. Select thelanguage required from English, French, German, Spanish or Italian.UnitsThe photometer offers the choice of result expressed in mg/l, ppm, mmol/l,μmol and g/l.Battery LevelA battery level indicates the remaining battery life. At least 3.0V is required forsuccessful operation of the instrument.