2INDEXOPERATING PRINCIPLE ................................................................................. 3Power Supply .................................................................................................. 4Replacing the Batteries .................................................................................... 4GENERAL PHOTOMETER OPERATION ........................................................ 5Operating Modes ........................................................................................... 5SYSTEM MODE................................................................................................ 6Back Light ...................................................................................................... 6Language Options.......................................................................................... 6Units ............................................................................................................... 6Battery Level .................................................................................................. 6TAKING PHOTOMETER READINGS .............................................................. 7Program Numbers and Test Instructions ....................................................... 7Blank and Sample Tubes............................................................................... 7Light Cap........................................................................................................ 7Getting the Best Results ................................................................................ 8Taking Test Readings .................................................................................... 8Continuation Tests (Certain Tests Only)........................................................ 9Favourite Tests List...................................................................................... 10Expressing Different Chemical Forms ......................................................... 10Reading in Transmittance and Absorbance................................................. 10Timer ............................................................................................................ 10CARE AND MAINTENANCE .......................................................................... 11Cleaning the Optics...................................................................................... 11SERVICE REQUIREMENT............................................................................. 11ERROR MESSAGES ...................................................................................... 12GUARANTEE .................................................................................................. 12