1 Method basis: resorcinol spectrophotometry 2 Measurement range: (0~100.0)mg/L 3 Accuracy:when ≤2.0mg/L,≤±0.2mg/L;when>2.0mg/L,≤±10% 4 Repeatability:≤5% 5 Measurement period: The minimum measurement period is 50 minutes (depending on the length of the digestion time). According to the actual water sample, the digestion time can be arbitrarily modified at (10 ~ 45) min 6 Sampling period: The time interval (1~999min) can be adjusted arbitrarily and the whole point is Selected 7 Calibration cycle: manual calibration or set cycle for automatic calibration. 8 Maintenance period: usually once a month, about 30 minutes each time. 9 Environmental requirements: indoor temperature adjustable, recommended temperature (5 ~28)ºC; humidity ≤ 90% (no condensation). 10 Power:AC(220±22)V,(50±5)Hz,5A 11 Size:Length550×Width400×High1500mm 12 Other: Abnormal alarm and power failure will not lose data; Touch screen display and command input After abnormal reset and call after power failure, the instrument automatically discharges residual reactants in the instrument and automatically resumes working condition.