Range FNU Mode 0.00 to 9.99; 10.0 to 99.9; 100 to 1000 FNU FAU Mode 10.0 to 99.9; 100 to 4000 FAU NTU Ratio Mode 0.00 to 9.99; 10.0 to 99.9; 100 to 4000 NTU 0.00 to 9.99; 10.0 to 99.9; 100 to 980 EBC NTU Non-Ratio Mode 0.00 to 9.99; 10.0 to 99.9; 100 to 1000 NTU 0.00 to 9.99; 10.0 to 99.9; 100 to 245 EBC Resolution FNU Mode 0.01; 0.1; 1 FNU FAU Mode 0.1; 1 FAU NTU Ratio Mode0.01; 0.1; 1 NTU / 0.01; 0.1; 1 EBC NTU Non-Ratio Mode 0.01; 0.1; 1 NTU / 0.01; 0.1; 1 EBC Accuracy @25°C FNU Mode ±2% of reading plus stray light FAU Mode ±10% of reading NTU Ratio Mode±2% of reading plus stray light / ±5% of reading above 1000 NTU NTU Non-Ratio Mode ±2% of reading plus stray light Range Selection automatic Repeatability ±1% of reading or stray light, whichever is greater Stray Light < 0.1 NTU (0.05 EBC) Light Detector silicon photocell Light Source IR LED Method ISO 7027 Method Measuring Mode normal, average, continuous. Turbidity Standards <0.1, 15, 100, 750 FNU and 2000 NTU Calibration two, three, four or five-point calibration Log Memory 200 records PC Connectivity USB Environment 0°C (32°F) to 50°C (122°F); max 95% RH non-condensing Power Supply 12 Vdc power input Dimensions / Weight 230 x 200 x 145 mm (9 x 7.9 x 5.7”) / 2.5 Kg (88 oz.)