SX731 Portable pH/ORP/EC/TDS/Salinity/Resistivity Meter
Apera Instruments SX731 Portable pH/ORP/EC/TDS/Salinity/Resistivity Meter, measuring (-2.00 to 19.99) pH. Runs on 2 AA batteries (1.5V ×2).
| Measuring Range | (-2.00 to 19.99) pH; Conductivity: (0.00 to 19.99) μS/cm, (20.0 to 199.9) μS/cm (200 to 1999) μS/cm, (2.00 to 19.99) mS/cm (20.0 to 199.9) mS/cm TDS: (0 to 100) g/L; Salinity: (0 to 100) ppt Resistivity: (0 to 100) MΩ·cm |
|---|---|
| Resolution | 0.1/0.01 pH; 0.01/0.1/1 μS/cm; 0.01/0.1 mS/cm; 1 mV |
| Accuracy | Instrument: ±0.01 pH; Total: ±0.02 pH; Device: ±1.0 F.S, Total: ±1.5% F.S; Device: ±0.1% FS, Total: ±15 mV |
| Data Content | Serial number, measured value, measuring unit and temperature |
| Data Storage | 300 data sets |
| Dimensions & Weight | Meter: (65×120×31) mm/180 g Complete set: (255×210×50) mm/1490 g |
| Electrode Constant | 0.1 / 1 / 10 cm-1 |
| Input Current | ≤2×10-12 A |
| Input Impedance | ≥1×1012Ω |
| IP Rating | IP57 |
| Measuring Range (mV/ORP/EH) | -1999mV to 0 to 1999mV |
| Quality and safety certification | CE, ISO 9001:2015 |
| Reference Temperature | 25°C, 20°C, and 18°C |
| Stability | ±0.01 pH/3h |
| Temperature Compensation | (0 to 100) °C (automatic); (0 to 50) °C (automatic) |
| Power Supply | 2 AA batteries (1.5V x2) |
| Manufacturer | Apera Instruments |
| MPN | AI467 |
| Item number | AI467 |
The Apera Instruments SX731 is a multi-parameter portable meter designed for laboratory-grade measurement of pH, ORP (redox potential), conductivity (EC), TDS, salinity, and resistivity in a variety of water solutions. Built for field and lab use, it features IP57 dust and water protection, a rugged design, and a hard carrying case, making it a reliable tool in harsh environments.
With high-precision electrodes including the 201T-S pH/Temp. electrode, 301Pt-S ORP electrode, and the 2301T-S conductivity/temp. electrode featuring BPB (Brush-resistant Platinum Black) technology, the SX731 delivers fast, accurate, and repeatable results. The digital filtering technology ensures quick response and improved measurement accuracy. Both the pH and conductivity electrodes offer automatic temperature compensation for stable readings across varying conditions.
This meter allows easy switching between EC, TDS, salinity, and resistivity. It also features 1 to 3-point pH calibration and 1-point EC calibration, with storage for up to 300 data sets.
Key Features
- Multi-parameter measurement – pH, ORP, EC, TDS, salinity, resistivity, and temperature
- Includes 3 high-quality electrodes – pH, ORP (no calibration required), and EC/temp.
- Brush-resistant Platinum Black (BPB) conductivity electrode with wide range (0–200 mS/cm)
- Automatic temperature compensation for pH and conductivity
- Quick, accurate ORP readings using a platinum sensor – easy to clean and maintain
- Fast calibration – 1-3 point pH and 1-point EC
- Digital filter technology – boosts response time and accuracy
- Stores 300 data sets – recall results easily during field work
- IP57-rated waterproof and dustproof – ideal for rugged environments
- 3-year manufacturer’s warranty (6 months for electrodes)
Complete Set Includes
SX731 multi-parameter meter
201T-S pH/Temp. electrode
301Pt-S ORP electrode (platinum sensor)
2301T-S conductivity/temp. electrode (BPB technology)
Calibration solutions:
pH 4.00 (50 ml)
pH 7.00 (50 ml)
pH 10.01 (50 ml)
1413 µS EC solution
User manual
2x AA batteries
Screwdriver
Rugged carrying case
Product documents
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