Product Introduction
A sensor (English name: transducer/sensor) is a detection device that can feel the information being measured, and can transform the sensed information into electrical signals or other required forms of information output according to a predetermined law to satisfy the information Requirements for transmission, processing, storage, display, recording, and control.
Product parameter
1. Heating voltage: 5±0.2V (DC)
2. Working current: 5-10mA
3. Detection concentration range: PHO-14 4. Detection temperature range: 0-80°C
5. Response time: <5S
6. Stability time: <60S
7. Component power consumption: <0.5W
8. Working temperature: -10~50°C (nominal temperature 20°C) 9. Working humidity: 95%RH (nominal humidity 65% RH)
10. Output mode: analog voltage signal output
11. With temperature compensation output
The refillable pH composite electrode has a dosing hole on the electrode shell. When the external reference solution of the electrode is lost, the dosing hole can be opened to replenish the KCl solution. The non refillable pH composite electrode is equipped with gel-like KCl, which is not easy to lose and has no liquid filling hole.
The characteristic of the rechargeable pH composite electrode is that the reference solution has a higher permeation rate, the liquid junction potential is stable and reproducible, and the measurement accuracy is higher. And when the reference electrode is reduced or contaminated, the KCl solution can be supplemented or replaced, but the disadvantage is that it is more troublesome to use. When using the refillable pH composite electrode, the filling hole should be opened to increase the liquid pressure and accelerate the electrode response. When the liquid level of the dielectric fluid is lower than the filling hole 2cm, new dielectric fluid should be added in time.
The non-rechargeable pH composite electrode is characterized by simple maintenance and convenient use, so it has also been widely used. However, when used as a laboratory pH electrode, under long-term and continuous use conditions, the KCl concentration at the liquid junction will decrease, which will affect the accuracy of the test. Therefore, when the non-rechargeable pH composite electrode is not in use, it should be immersed in the electrode soaking solution, so that the electrode performance will be very good in the next test. However, most laboratory pH electrodes are not long-term and continuous tests, so this structure is not The impact of accuracy is relatively small.
Two: Matters needing attention when using the electrode probe
1. Use fresh buffer
2. Open the electrode protective cover
3. Measure the gap and rinse the electrode with deionized water 4. Stir the buffer and the sample: a) Stir at the same speed all the time; b) Stir first, then measure
5. When preparing the pH electrode, rinse the electrode with distilled water before and after the measurement. Use a lint-free cloth to absorb the excess water on the electrode tip to avoid rubbing the electrode bulb, otherwise it will generate static electricity and i nterfere with the accurate measurement of pH.
6. Make sure that the temperature of the buffer is the same as that of
the sample. If the sample temperature is different, please use a
temperature compensation probe for temperature compensation. 7. Periodically check the electrode slope with a two-point calibration method. When the electrode reading drifts or the slope is lower than 92%, please refer to the cleaning of the electrode to clean the electrode.
Three: Maintenance of the electrode probe
1. Cleaning the electrode
General cleaning solution-soak the electrode in 0.1M HCl or 0.1M HNO3 solution for 15 minutes, and then soak the electrode in the electrode storage solution for 30 minutes.
2. The liquid junction is blocked (salt precipitation) Causes: hard water, mud, organic dirt, plankton microorganisms, moss, etc. Attached to the water-permeable sand core around the bulb and PTFE, causing the external reference electrode to not work properly.
Solution:Soak the electrode in hot water (60°C) for 15-20 minutes; soak the electrode in a hot saturated KCI (60°C) solution for 20-30 minutes and cool to room temperature; soak the electrode in pH 4 buffer for 20 to 30 minutes minute. Check for excessive crystals. If so, rinse the crystals with deionized water and check if the flow rate is normal. If not, soak the electrode in hot water (60°C) for 15-20 minutes; soak the electrode in hot saturated KCI (60°C) in the solution for 20-30 minutes, and cool to room temperature; soak the electrode in pH4 buffer for 30 minutes. Soak the electrode tip in concentrated HCI for 5-10 minutes, rinse the electrode, and check whether the electrolyte flow rate is normal. If the junction is still blocked, pull the junction (don’ t touch the glass bulb)
4: The precipitation of inorganic substances on the pH sensitive membrane Cause: Inorganic sample measurement Solution: clean with EDTA, ammonia or acid
5: pH sensitive membrane dehydration
Causes: improper storage, long-term use, high-temperature operation or strong alkaline solutions, resulting in slow and unstable response Solution: activated electrode
Soak the electrode in 0.1 M HCl for 1 minute, rinse with tap water for 30 seconds, soak the electrode in 0.1 M KOH for 1 minute, rinse with tap water for 30 seconds, calibrate the test electrode with buffer solution, if it still does not work, repeat the above steps, at most 3 times 6: The PH electrode is used for a long time, and the necessary cleaning and maintenance work is not performed correctly on the electrode in the tested environment, which causes the electrode data to be unstable and other factors. Solution: After using the electrode for 2-3 months, clean the electrode bulb and check the liquid junction. Solution: Take the electrode out of the environment to see if there is any dirt on the surface of the bulb. If there is any dirt, wipe it with ethanol cotton and then clean it with deionized water.
[Note that the bulb is fragile, pay attention to during the wiping process]. Then check the liquid junction to see if there is any contaminants attached to the surface. If there is, you can use deionization to rinse, or you can shake the electrode back and forth in the measuring cup. If the water is not clean, change the water until the dirt disappears.. Then wash the electrode and place it in the activation solution for 8 hours, then measure it in the standard solution to restore the measurement state.