水硬度離子選擇電極
專門測量0.5 ppm至飽和（1x10-5 M至飽和）水硬度（鈣和鎂）濃度。
應用包括：水軟化系統，飲用水和礦泉水，海水。
| Model # | WHA1502 |
| Slope | 25 ± 3 mV between 10-100 ppm @ 25°C |
| Reproducibility | ± 2% |
| Interferences | Zn+2, Fe+2, Cu+2, Ni+2 |
| Temperature Range | 0 to 40° C (if calibrated at that temperature) |
| Pressure Range | 0 to 30 psi |
| Response Time | 95% response in 30 seconds |
| Storage | Long term, store dry Short term, store in dilute calcium standard |
| Concentration Range | 0.5 ppm to Saturated (as Ca+2) (1 x 10-5 M to Saturated) |
| pH Range | 5 to 10 pH |
| Resistance | 100 megaohms |
| Care, Maintenance & Cleaning | Treat with distilled water followed by calcium standard |
| Isopotential Point | 1 ppm |
| On-Line Capability | Yes |
| Applications | Water Softening Systems, Drinking and Mineral Waters, Sea Water |