1. VASTHI Dissolved Oxygen Analyzer MODEL No : VDO-200 Working Principle Fluorescence method Dissolved oxygen sensor is based on the physics of specic substances on the activity of uorescence quenching principle. The blue light from a light- emitting diode (LED) illuminates the uorescent substance on the inner surface of the uorescent cap. The uorescent substance on the inner surface is excited to emit red light. By detecting the phase difference between the red and blue light, To calculate the concentration of oxygen molecules, through the temperature and pressure automatically compensate for the nal output value. Features No electrolyte, no polarization No need to consume oxygen, not affected by the ow rate Built-in temperature sensor, automatic temperature compensation Not subject to sulde and other chemical substances interference Drift small, fast response, more accurate measurement maintenance-free, longer life cycle, the use of lower cost Fluorescent cap replacement is simple RS-485 interface, MODBUS-RTU protocol

2. VASTHI Dissolved Oxygen Analyzer Technical Parameters Model VDO- 200 Fluorescence method 0-20.00mg/L 0.01mg/L, ±5%F.S., RS485(Modbus/RTU) 0^-45°C, <0.2MPa -5^-65°C 3/4" NPT screw thread, immersion mounting 5m, other lengths can be customized <1W 230 V , 50 Hz IP68 Measuring principle Range range Resolving power Accuracy Signal output Working conditions storage temperature Installation method Cable length Power consumption power supply Protection level for sensor 0.1°C ±0.5°C VASTHI Plot no.: 21& 22, Block No.: 24, Phase - IV Auto Nagar, GUNTUR - 522 011, Andhara Pradesh, INDIA Tel : +91 863 2238 667, + 91 738 2708 685, +91 958 1678 685 www.vasthi.com email ID: info@vasthi.com sales@vasthi.com