1、 Product Introduction:
The constant temperature bath of the dissolved oxygen analyzer calibration device complies with the JJG291-2018 calibration regulations and is specially developed for dissolved oxygen analyzers. It uses a fully enclosed compressor refrigeration system with multiple overload protection devices such as overheating and overcurrent, and uses a microcomputer intelligent PID automatic control system with over temperature alarm function, soft key lock function, LED dual window display, and touch soft key operation.
2、 Technical indicators:
1. Working temperature range: 0-50 ℃
2. Temperature fluctuation: ± 0.05 ℃ (test medium: water)
3. Temperature measurement value digital display resolution: 0.01 ℃
4. Temperature setting value digital display resolution: 0.01 ℃
5. Power supply: 220V, 50Hz
3、 Testing method:
1. Preparation of anaerobic water
Add 250ml of distilled water to a 500ml beaker, then add 500mg of sodium sulfite and trace amounts of divalent cobalt salts, such as hexahydrate cobalt oxide as catalyst, stir evenly before use.
2. Preparation of saturated dissolved oxygen water
Inject 2/3 volume of fresh distilled water (about 8L) into the constant temperature bath of the dissolved oxygen analyzer calibration device, float the porous plastic float cover on the water surface, adjust the water temperature to the required temperature for calibration, start the mixer to stir the water sample, and add a bubbler (i.e. air pump) to continuously aerate the water for more than 60 minutes to stop aeration. After the water is still for 30 minutes, it can be used for calibration.