Principle and Application:
The chemical oxygen demand (COD) value of the sample was determined by spectrophotometry after high-temperature catalytic digestion in a strong oxidant. Widely used for the determination of chemical oxygen demand (COD) in surface water, groundwater, domestic sewage, and industrial wastewater, especially suitable for rapid water quality emergency testing in the field and on-site.

characteristic:
Added the ability to measure total nitrogen (TN), ammonia nitrogen (NH3-N), and total phosphorus (TP).
No preheating required, it can be measured immediately upon startup. Testing a sample in 12 seconds results in stable and reliable performance.
Greatly simplifies the user's measurement work: fast and convenient, using pre packaged reagents, users do not need to prepare reagents, do not need to make working curves, and can directly measure (users can also self prepare reagents and build their own curves).
● Easy to operate: Simply insert the sample tube and the concentration will be automatically displayed without the need for training.
Extremely energy-efficient: With only 2 # 5 rechargeable batteries, it can be continuously powered on for 100 hours (equivalent to 12 working days) with a single charge, and can test up to 30000 samples. It can also be connected to a 220V power adapter.
Good compatibility: Equipped with an SD card (2G, varying with the market), it can be easily connected to a computer. Data is read out in EXCEL format with time records, and users can view and edit it themselves.
● Massive storage: With a large capacity SD card as the data storage, data can be saved almost for life without worrying about being fully stored.
● Optional pre packaged reagents can be selected.

Instrument performance
Chemical Oxygen Demand (COD) Measurement Range: 20-150mg/L Accuracy: 0.1 mg/L
Chemical Oxygen Demand (COD) Measurement Range: 100-1500mg/L Accuracy: 1 mg/L
Chemical Oxygen Demand (COD) measurement range: 1000-15000mg/L accuracy: 10 mg/L
Total nitrogen (TN) measurement range: 0-25mg/L accuracy: 0.1 mg/L
Total nitrogen (TN) measurement range: 5-150mg/L accuracy: 0.1 mg/L
Total phosphorus (TP) measurement range: 0.05-2mg/L accuracy: 0.01 mg/L
Total phosphorus (TP) measurement range: 0.5-10mg/L accuracy: 0.1 mg/L
Total phosphorus (TP) measurement range: 1-20mg/L accuracy: 1 mg/L
Ammonia nitrogen (NH3-N) measurement range: 0.025-2mg/L accuracy: 0.01mg/L


Technical Parameter
Wavelength range: 420nm, 610nm
Wavelength selection: automatic
Indication error: within ± 8%
Repeatability: ≤ 3%
Stability: absorbance value less than 0.005A within 20 minutes
Reading mode: absorbance, concentration
Light source lamp: Light emitting diode (LED)
Power supply: DC3V (2 # 5 rechargeable batteries). Charging once can keep the device running continuously for 100 hours, and it can also be connected to a 220V power adapter.

Supporting COD Dissolver: (ECH-III)
Simultaneously heat and digest 32 test tubes (Φ 16), with PID program heating and insulation power matching, ensuring uniform heating.
Heating range: room temperature -200 ℃, power: 1000W, heating temperature and holding time can be freely set.
The sample does not need to be transferred, and after heating and digestion, it is directly placed into the COD analyzer for measurement.