Alalis PI5100-Ca Benchtop Calcium Ion Concentration Meter

Overview

The Alalis PI5100-Ca is a high-precision benchtop ion concentration meter engineered for reliable, trace-level quantification of calcium ions (Ca²⁺) in aqueous environmental, industrial, and laboratory samples. It operates on the principle of potentiometric measurement using a solid-state or liquid-membrane calcium-selective electrode (Ca-ISE), generating a Nernstian voltage response proportional to the logarithm of free Ca²⁺ activity. The instrument supports direct pX (−log[ion]) readout as well as concentration units—mol/L, mg/L, and ppm—enabling seamless integration into regulatory reporting workflows. Designed for compliance-critical applications, it meets fundamental metrological requirements aligned with ISO/IEC 17025 calibration practices and supports GLP-compliant data integrity through timestamped storage, audit-ready records, and electronic signature readiness.

Key Features

• Potentiometric ion detection with dedicated Ca²⁺-selective composite electrode, optimized for low-interference performance in complex matrices including drinking water, wastewater, boiler feedwater, and soil leachates.
• Multi-point automatic calibration (2–5 points) for ion mode; pH calibration from 1–5 points with guided prompts and real-time electrode diagnostics.
• Simultaneous dual-parameter measurement: Ca²⁺ concentration and temperature, with independent auto/manual temperature compensation (0–60.0 °C for ion mode; −10–110.0 °C for pH/mV).
• Four selectable concentration units—pX, mol/L, mg/L, ppm—with unit-switching capability during measurement and post-acquisition data review.
• GLP-compliant data management: 1000-group internal memory (manual/auto-triggered), time-stamped entries, USB export to PC with included software, and CSV-compatible output for LIMS integration.
• Robust physical design: IP54-rated enclosure with sealed electrode ports and rubber protective caps; wide-view backlit LCD (90 × 68 mm) supporting simultaneous display of ion value, temperature, stability indicator, and system status.
• Advanced operational modes: high-purity water pH measurement (low-conductivity correction), ammonia-added pure water pH mode, and redox (E_H) potential measurement up to ±1999.9 mV.

Sample Compatibility & Compliance

The PI5100-Ca is validated for use with liquid-phase environmental samples meeting standard EPA Method 9035 (Ion-Selective Electrode Procedures) and ASTM D511-21 (Calcium in Water). It accommodates samples with total dissolved solids (TDS) ≤ 5000 mg/L and turbidity < 5 NTU without filtration. Electrode compatibility includes standard Ca²⁺-ISEs with polymeric or crystalline membrane configurations. All measurements adhere to ISO 10523 (pH determination) and ISO 14911 (ion chromatography reference methodology for validation). The device supports traceability via user-defined calibration certificate logging and conforms to basic elements of FDA 21 CFR Part 11 when used with secure USB transfer protocols and controlled access environments.

Software & Data Management

Data acquisition and reporting are enabled via bundled Windows-compatible communication software, supporting real-time monitoring, batch export, and customizable report templates. Each stored record includes measured value, unit, temperature, date/time stamp, electrode ID (if tagged), calibration history reference, and operator ID field. Audit trail functionality logs all configuration changes—including unit switches, temperature compensation toggles, and factory reset events—with immutable timestamps. Exported datasets comply with ASTM E1461-20 metadata conventions, facilitating import into ELN systems or statistical analysis platforms such as JMP or Minitab.

Applications

• Regulatory monitoring of calcium hardness in municipal drinking water per WHO Guidelines and EU Directive 98/83/EC.
• Process control in desalination plants and cooling tower water treatment where Ca²⁺ scaling potential must be continuously assessed.
• Environmental field labs performing surface water and groundwater characterization under national water quality standards (e.g., China’s GB 3838-2002, US EPA Clean Water Act parameters).
• Pharmaceutical water systems (PW, WFI) verifying calcium residuals prior to sterilization cycles.
• Academic research involving ion transport kinetics, membrane selectivity studies, and chelation titration validation.

FAQ

What is the recommended maintenance schedule for the calcium ion electrode?
Electrode conditioning should be performed before first use and after extended storage: soak in 0.001 mol/L CaCl₂ solution for ≥2 hours. Routine cleaning involves rinsing with deionized water and gentle wiping with lint-free tissue; avoid abrasive agents or organic solvents.
Can the PI5100-Ca measure other divalent cations besides Ca²⁺?
While calibrated specifically for Ca²⁺, the instrument platform supports user-defined ion setup for Mg²⁺, Cu²⁺, or Pb²⁺—provided a compatible ISE is connected and selectivity coefficients (log K_Ca,X) are entered manually to correct for cross-sensitivity.
Is the device suitable for continuous online monitoring?
No—it is designed for discrete batch analysis. For continuous deployment, Alalis offers parallel industrial transmitter models (e.g., PI6000 series) with 4–20 mA output and RS485 Modbus RTU interface.
How does the instrument handle ionic strength variation in low-conductivity samples?
The built-in ionic strength adjustment (ISA) function allows manual input of background electrolyte concentration (e.g., 0.1 M KNO₃), enabling activity-to-concentration conversion per the Davies equation—critical for accurate Ca²⁺ quantification in ultrapure water.
Does the USB interface support direct connection to LIMS without intermediary software?
Yes—the device enumerates as a CDC ACM virtual COM port. With appropriate driver installation and LIMS-side serial protocol configuration (9600 baud, 8N1), raw ASCII data streams can be ingested directly, satisfying automated data capture requirements under ISO/IEC 17025 Clause 7.7.