TURBIDITY METER Turb® 555 offers highly precise optics with several detectors and therefore allows nephelometric (90° stray light) measurement for drinking water as per DIN ISO 27027/ EN ISO 7027 / US EPA 180.1, transmission and ration measurements (ratio method). Ratio procedures reduce the influence of sample colorations and interference effects of stray light with high turbidity. Comprehensive AQA functions such calibration interval monitoring with protocol, password protection for calibration and setup access fulfill the quality assurance requirements. The calibration up to 4000 NTU takes place with highly precise AMCO Clear® polymer standards (0.02 – 10.0 - 100 – 1750 NTU) that are called secondary standard for drinking water as per DIN ISO 27027, EN ISO 7027 or approved as primary standards as per US EPA. As an option, the measuring range can be expanded by a 10,000 NTU standard. AMCO Clear® standards Polymer calibration standards excel Formazine by significantly higher accuracy and stability without drifting, which increases the measuring accuracy significantly: Manufacturing tolerance of only ±1% for highest result accuracy Long-term stable particle distribution and size No health hazard Easy to dispose of N.I.S.T. traceability Flow-through and continuous flow measurement of up to 4 bar possible. The measurement data can be sent to a PC or a printer timer-controlled via the RS232 interface. Measuring ranges    NTU 0 … 10000 FNU 0 … 10000 (IR) Resolution (NTU)    0.0001 for range 0.0001 … 9.9999 0.001 for range 10 … 99,999 0.01 for range 100.00 … 999.99 0.1 for range 1000.0 … 9999.9 Accuracy (NTU)    0 … 1000: 0.01 or ±2% of the value  1000….4000: ±5% of the value 4000 …10000: ± 10% of the value Reproducibility    0.01 NTU or ± 1% of the measured value Cuvette size    28x70 mm, 25 ml sample volume Power supply    Power cable 100-240 VAC ±10%