In a strong acid solution with a pH value of less than 1, there will be an acid error, and the measured value is greater than the sample value; in a strong alkaline solution with a pH value greater than 10, there will be an alkali error, and the measured value will be smaller than the sample value; not only the measured value error, strong acid The strong alkali solution will also corrode the glass membrane, and the electrode will be damaged quickly, and the damage will be more serious at high temperature.
Hydrofluoric acid resistant, strong alkali resistant, high temperature resistant glass film


| FZ | 831 | 833 | 841 | 843 | 861 | 863 |
| pH range | 0-12pH | 0-12pH | 1-14pH | 1-14pH | 1-13pH | 1-13pH |
| temperature range | 0~100℃ | 0 ~100℃ | 0~130℃ | 0~130℃ | 0 ~130℃ | 0~130℃ |
| temperature probe | none | NTC 30KΩ | none | NTC 30KΩ | none | NTC 30KΩ |
| glass film | HF | HF | HA | HA | PHY | PHY |
| Membrane impedance | <400MΩ | <400MΩ | <500MΩ | <500MΩ | <500MΩ | <500MΩ |
| Junction | ceramic core | ceramic core | ceramic core | ceramic core | Porous PTFE | Porous PTFE |
| reference system | silver ion trap | silver ion trap | silver ion trap | silver ion trap | silver ion trap | silver ion trap |
| reference electrolyte | 3M KCL | 3M KCL | 3M KCL | 3M KCL | 3M KCL gel | 3M KCL gel |
| Shell material | lead-free glass | lead-free glass | lead-free glass | lead-free glass | lead-free glass | lead-free glass |
| electrode size | φ12*120mm | φ12*120mm | φ12*120mm | φ12*120mm | φ12*120mm | φ12*120mm |
| Interface/Cable | BNC/1m | BNC/1m | BNC/1m | BNC/1m | BNC/1m | BNC/1m |