Sanxin EC5 Pocket-Sized Conductivity Meter
| Brand | Sanxin Peri |
|---|---|
| Origin | Shanghai, China |
| Manufacturer Type | Direct Manufacturer |
| Product Category | Domestic (China-Made) |
| Model | EC5 |
| Price | USD 108 |
| Measured Parameter | Single-Parameter (Conductivity/TDS/Salinity/Temperature) |
| Form Factor | Pen-Style Portable |
| Intended Use | Laboratory & Field Applications |
| Conductivity Range | 0–20.00 mS/cm (equivalent to 0–20,000 µS/cm) |
| TDS Range | 0–10.00 ppt (with conversion factor 0.50) |
| Salinity Range | 0–10.00 ppt (NaCl scale) |
| Resistivity Range | Not applicable (deduced only) |
| Temperature Range | 0–50 °C |
| Accuracy | ±1% FS (Conductivity), ±0.5 °C (Temperature) |
| Minimum Resolution | 0.01 mS/cm / 0.1 µS/cm |
| Calibration | 1–3-point automatic calibration (using 1413 µS/cm and 12.88 mS/cm standard solutions) |
| IP Rating | IP67 |
| Power Supply | 4 × AAA alkaline batteries (DC 3 V), >200 h continuous operation |
| Dimensions (Instrument) | 40 × 40 × 178 mm |
| Weight (Instrument) | 133 g |
| Enclosure | Rugged carry case (255 × 210 × 50 mm, 438 g) including calibration standards, storage vials, KCl soaking solution, lanyard, and batteries |
Overview
The Sanxin EC5 Pocket-Sized Conductivity Meter is a compact, field-ready electrochemical instrument engineered for rapid, reliable measurement of electrical conductivity, total dissolved solids (TDS), salinity, and temperature in aqueous solutions. Based on two-electrode AC conductometric principles with frequency-modulated excitation, the EC5 eliminates polarization errors commonly observed in DC-based systems and ensures stable readings across varying ionic strengths—from low-conductivity deionized water to high-salinity brines. Its pen-style form factor, combined with IP67-rated ingress protection and buoyant housing, enables uninterrupted operation in humid, dusty, or splash-prone environments—making it suitable for routine QC checks in water treatment plants, aquaculture monitoring, hydroponic nutrient management, swimming pool maintenance, and industrial cooling tower surveillance. The device operates without external power sources or PC connectivity, delivering lab-grade repeatability (±1% full-scale accuracy) in a handheld platform compliant with ISO 7888 and ASTM D1125 guidelines for conductivity testing.
Key Features
- True pen-style design with integrated sensor and electronics—no detachable cables or external probes required
- Dual-color backlit STN LCD (blue for measurement mode; green for calibration mode) with 180° viewing angle and auto-dimming function
- Smart microcontroller architecture enabling auto-ranging, auto-calibration (1–3 points), manual/auto HOLD, low-battery warning, and 8-minute auto-shutdown
- Replaceable two-electrode conductivity cell with platinum black plating for enhanced surface area and long-term stability
- IP67-certified enclosure: fully dust-tight and submersible up to 1 m for 30 minutes; instrument floats on water surface
- Pre-configured TDS conversion factor (0.50) aligned with USP and EPA Method 120.1 for consistent reporting
- Integrated temperature compensation (NTC thermistor, 0–50 °C) with automatic linear compensation (0–3.0 %/°C)
Sample Compatibility & Compliance
The EC5 is validated for use with clear, non-viscous, non-abrasive aqueous samples—including freshwater, seawater dilutions, nutrient solutions, chlorinated pool water, and municipal effluent. It is not intended for use with organic solvents, highly viscous fluids, or suspensions containing particulates >50 µm. All measurements adhere to the fundamental relationship σ = G × Kcell, where measured conductance (G) is scaled by the fixed cell constant (Kcell = 1.0 cm−1). Device firmware and calibration protocols comply with GLP documentation requirements, supporting traceable calibration logs (date, standard used, deviation) stored in non-volatile memory. While not FDA 21 CFR Part 11–compliant due to lack of electronic signature capability, its calibration history and measurement data meet basic audit-readiness criteria for ISO/IEC 17025-accredited laboratories performing routine environmental or process water analysis.
Software & Data Management
The EC5 operates as a standalone instrument with no embedded software stack or wireless interface. All configuration, calibration, and measurement functions are managed via tactile button controls and interpreted directly on the LCD. No proprietary drivers, firmware updates, or cloud synchronization are supported. However, its standardized output format—displaying conductivity (mS/cm or µS/cm), TDS (ppm or ppt), salinity (ppt), and temperature (°C) simultaneously—enables seamless transcription into LIMS or Excel-based QA records. Each unit ships with printed calibration certificates for included 1413 µS/cm and 12.88 mS/cm traceable standards (certified per ISO/IEC 17025 by an accredited provider), facilitating internal calibration verification and external audit readiness.
Applications
- Hydroponics & greenhouse operations: real-time monitoring of nutrient solution EC to prevent osmotic stress
- Aquaculture farms: daily salinity and conductivity checks in hatcheries, raceways, and recirculating aquaculture systems (RAS)
- Municipal water facilities: spot-checking of treated drinking water, distribution system residuals, and wastewater influent/effluent
- Industrial cooling circuits: detecting scaling potential and corrosion risk through conductivity drift analysis
- Education labs: undergraduate electrochemistry experiments demonstrating Kohlrausch’s law and ion mobility relationships
- Swimming pool & spa maintenance: verifying sanitizer concentration indirectly via conductivity shifts correlated with chloride buildup
FAQ
What calibration standards are included with the EC5?
The instrument ships with two certified conductivity standards: 1413 µS/cm (±1%) and 12.88 mS/cm (±1%), each supplied in sealed vials with batch-specific certificates of analysis.
Can the EC5 measure resistivity directly?
No. Resistivity is mathematically derived from conductivity (ρ = 1/σ) but is not displayed or stored as a discrete parameter.
Is the electrode replaceable, and what is its typical service life?
Yes—the integrated two-electrode cell is user-replaceable (part number EC5-EL). Under normal use with proper KCl storage and periodic cleaning, expected functional life exceeds 18 months.
Does the EC5 support custom TDS conversion factors?
No. The device uses a fixed 0.50 multiplier, consistent with NaCl-based calibration and widely accepted for general-purpose water quality assessment.
How is temperature compensation applied during measurement?
Automatic linear compensation is enabled by default, using a built-in NTC thermistor and user-selectable β-coefficient (0.0–3.0 %/°C); factory setting is 2.0 %/°C per ISO 7888.
