COD, BOD, TSS water quality monitor for STP and ETP

Vasthi Instruments are global leaders in manufacturing of COD, BOD, TSS water quality monitor for STP and ETP and have been supplying instruments to customers worldwide, Our multidisciplinary team of scientists, physicians, engineers, and regulatory consultants with decades of global experience brings you the quintessential mechanism that provides complete safety accuracy and durability. Vasthi Instruments was formed with visionary thinking and innovative ideas resulting in innovative products and solutions. We enhance our product quality by the continuous process of research and development. We have WIDE range of models to suite various site conditions and processes.

Catalogue For Water Analyzer-VEMS-4000


COD, BOD, TSS water quality monitor for STP and ETP VEMS-4000 that provides digital sensor technology and covers Dissolved Oxygen, Total Suspended Solid(TSS), Liquid Density and Conductivity measurements. COD, BOD, TSS water quality monitor for STP and ETP adopts the pulse xenon lamp as light source and the ultraviolet optical fiber spectrometer as detector is capable for real-time gathering of absorption spectrum of water pollutants ranging from 200nm to 800nm and real-time analysis of the content of water pollutants by means of chemometric algorithm technology. COD, BOD, TSS water quality monitor for STP and ETP includes two parts: the control box and the probe. The control box is installed in the analysis cabin and the probe is submerged in the water and fixed by means of mounting bracket the two parts are connected via cable. The control box provides power supply to the probe and at the same time receives the measurement value from the probe and displays them on the interface.


Model: VEMS-4000

  • It Requires no reagents, so it can save operating costs and will cause no secondary pollution .
    • The Reponce is quick (about 2 seconds ). It is suitable for the occasion where high real time performance is required , such as industrial process analysis .
  • Free from the interference of chloride ion .
    • It Adopts full-spectrum measurement and chemo metric algorithm analysis ,Which in comparison with the simple dual wave ength background subtraction technology, can measure more parameters and is less likely to be influenced by the compositional change of waste water.
    • All Components are independently researched and developed
    • It adopts pulse blowing method to clean the pollutants on the two window surfaces.                               The Instrument probe in the water measures organics in the water by means of xenon lamp . The calculation of the spectrum obtained after each measurement will produce a measured value, which will be transmitted to the control box and displayed.                                                                                                                                            • Optical Fiber on the main Interface . One measurement only takes several dozens of seconds . Mean While ,in the interval of measurement , the instrument will be automatically cleaned to prevent contaminants from being deposited on the surface of the lens .


Measuring Parameters COD,BOD,UV254,Nirate,TOC,DOC,Turbidity,TSS,Color,etc..
Measuring Rang As Customer required
Method Uv/Visible differential optical absorption spectroscopy, wavelength range   200-800nm
Power 230V  AC, 30w
Linearity 2%F.S.
Zero Gravity <1%F.S.
Range (COD) 0~50~200mg/l,greater range can be customized
Interval The shortest 60 seconds, the cycle can be set
Probes Depth <10m
Optical Path Can be adjusted according to the site condition
Working Temp 5°C~45°C
Enclosure Rating Ip65(secondary instrument)
Auto -Cleaning Can be set
Interface RS232/RS485(Baud rate can be set),2×4-20ma output
Probe Size 60*380.5mm
Probe Weight 5kg
Interace digital Ethernet (TCP/IP),RS-232 or RS-485 (Modbus RTU)
Power Supply 12-24VDC (±10%)
Output Data
Power Consumption <8W
Environmental Conditions
Sample Temperature +2…+40°C
Ambient Temperature +2…+40°C
Inflow velocity 0.1-10m/s
Performance Characteristics
Maintence effort Typically <0.5h/month
Calibration/maintenance interval 24 months
System compatibility Modbus RTU
Guarantee 1 year (EU:2year)
Max. pressure with sub Conn 30 bar
Max. Pressure with fixed cable 3 bar
Max .pressure in flow cell 1 ber,2-4 L/min
Protection type IP 68
Structural design
Housing material Stainless steel (1.4571/1.4404)or titanium(3.7035)
Weight Stainless steel ~3kg (with 10mm path)
Weight titanium ~2kg (with 10mm path)