This instrument is composed of a microbial membrane fastened to an oxygen electrode to form a microbial electrode. When a water sample containing saturated dissolved oxygen enters the circulation pool and comes into contact with the microbial sensor, the organic matter in the water sample that is soluble and biodegradable is affected by the bacteria in the microbial membrane, reducing the mass of oxygen diffused onto the surface of the oxygen meter. When the diffusion rate (mass) of biodegradable organic matter in the water sample reaches a constant value towards the bacterial membrane, the mass of oxygen diffusing onto the oxygen electric surface also reaches a constant value, thus generating a constant current. The difference between the constant current and the concentration of biodegradable organic matter in the water sample is quantitatively related to the decrease in oxygen, which can be used to convert the biochemical oxygen demand in the water sample.

1. Equipped with both domestic and imported microbial membranes, the dry membrane can be stored at room temperature for one year, and after activation, it can be used continuously for one month or intermittently for three months (it needs to be stored in the refrigerator when there is no sample testing).
2. Adopting constant temperature gas conduction, the temperature is more uniform and the constant temperature effect is better.
3. Adopting a dual pump pipeline, the sample and buffer solution are input separately, avoiding the cross influence of a single pump and ensuring more accurate measurement.
4. Sensor features: Three in one core sensor with reference electricity
5. Injection volume: Meet the requirement of injection volume ≥ 50ml in the standard

1. Measurement range: 2-400mg/L (the measurement range can be changed by adjusting the pump speed and sample contact time as needed, and samples with a concentration greater than 400mg/L need to be diluted)
2. Sample measurement time: 60 minutes per sample (including 5 minutes each for standard calibration and sample measurement, and 15 minutes each for three pipeline cleaning)
3. Calibration: Single point calibration using glucose glutamic acid
4. Display mode: LCD screen, 20 characters x 2 lines
5. Repeatability: ≤ 5%
6. Output: Recorder output, display output, print output
7. Adjustable temperature range: ≤ 35℃±0.2℃
8. Rated power supply: AC220V ± 22V, 50 Hz ± 1 Hz, 1.5A max
9. Dimensions: 370 (w) × 350 (d) × 300 (h) mm
10. Weight: 14kg
11. Environmental temperature: 5-40 ℃
12. Environmental humidity: ≤ 90%RH
13. Signal output: Microbial electrode 0-20 μ A
14. Electrical lifespan: greater than 2 years
15. Peripheral devices: standard solution, buffer solution, antibacterial pipeline, printer