- +86 571 8501 2111
- fpi-online@fpi-inc.com
- 459 Qianmo Road, Binjiang District, Hangzhou, China
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The Ion-Selective Electrode (ISE) Online Sensor is a probe-type intelligent sensor. It features compensation for temperature, pH, and interfering ions, and adopts an RS485 interface with standard Modbus protocol. The sensor enables in-situ measurement without the need for reagents or sample pre-treatment, offering low maintenance and high operational efficiency.
The measurement principle of ion-selective electrodes (ISEs) is based on the relationship between the activity and concentration of ions in an electrolyte solution. An ISE typically consists of two electrodes: a working electrode and a reference electrode. The working electrode selectively responds to the target ion, while the reference electrode provides a stable potential as a reference.
The working electrode is usually coated with a selective membrane that exhibits a specific response to a particular ion. When the target ion interacts with the selective membrane, a change in electric potential is generated. By measuring this potential change, the concentration of the ion can be determined.
where:
| Working principle | Ion selection electrode method | ||||||||
| Measurement factors | NH4N | Na+ | NO3N | F- | Cl- | ||||
| Product model | ISE NH4N-100 | ISE NH4N-200 | ISE NH4N-210 | ISE Na-200 | ISE Na-210 | ISE NO3N-200 | ISE F-200 | ISE Cl-200 | |
| Measurement factors | Ammonia nitrogen, temperature | Ammonia nitrogen, pH, temperature | Ammonia nitrogen, pH, K+, temperature | Na+, pH, temperature | Na+, pH, ammonia nitrogen, temperature | nitrate, Cl-, temperature | F-, pH, and temperature | Cl-, pH, temperature | |
| Measurement range（mg/L） | 0.1~1000 | 0.1~1000 | 0.1~1000 | 0.1~1000 | 0.1~1000 | 0.1~1000 | 0.1~10000 | 3~30000 | |
| / | pH 0~14 | pH 0~14 | / | / | / | pH 0~14 | pH 0~14 | ||
| Temperature 0~50 °C | Temperature0~50 °C | Temperature0~50 ℃ | Temperature0~50 ℃ | Temperature0~50 ℃ | Temperature0~50 ℃ | Temperature0~50 ℃ | Temperature0~50 ℃ | ||
| repeatability | ≤2%、<0.1pH、≤0.3℃ | ≤2%、≤0.3℃ | |||||||
| Measurement accuracy | ±5%or±0.1mg/L；Temperature < 0.3°C | ±5% or ±0.1mg/L;<0.1pH； Temperature < 0.3°C | ± 10% or ± 0.1mg/L; Temperature < 0.3°C | ± 10% or ± 0.5mg/L temperature < 0.3°C | |||||
| Compensation Scope: | / | pH 4~10 | pH 4~10K+；<100mg/L | NH4N+<100mg/L | / | Cl-<1000mg/L | pH 3.5-5 | / | |
| Low concentration drift (24h) | ±1%F.S | ||||||||
| Range drift (24h) | ±3%F.S | ||||||||
| Detection limit | 0.1mg/L | 0.05mg/L | 0.05mg/L | 0.1mg/L | 0.1mg/L | 3mg/L | |||
| resolution | 0.01mg/L | ||||||||
| Protection level | IP68 | ||||||||
| Communication interface | RS485, the standard Modbus protocol baud rate 9600 address bit default 50 | ||||||||
| Dimensions: | (φ33*146)mm, cable 10 meters (can be customized) | (φ50*251)mm, cable 10 meters (customizable) | (φ60*270)mm, cable 10 meters (can be customized) | (φ60*270)mm, cable 10 meters (can be customized) | (φ50*251)mm, cable 10 meters (customizable) | (φ60*270)mm, cable 10 meters (can be customized) | (φ50*251)mm, cable 10 meters (customizable) | (φ50*251)mm, cable 10 meters (customizable) | |
| Material | 316L stainless steel/PVC/titanium alloy optional | ||||||||
| weight | 0.2KG | 2KG | 1KG | 2KG | 1KG | 2KG | 1KG | 2KG | |
| Mounting threads | Upper end NPT3/4 thread | ||||||||
| Operating voltage | 9~36V DC | ||||||||
| MTBF | ≥ 1440h/time | ||||||||
| power consumption | 0.5w | ||||||||
| Calibration period | 1~3 months (depending on the water quality environment on site) | ||||||||
| Work environment | （0~50）℃ | ||||||||
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