KEM CHA-600 Automated Sample Changer for Potentiometric Titrators

Overview

The KEM CHA-600 Automated Sample Changer is a precision-engineered peripheral system designed exclusively for integration with KEM’s AT-710 series, AT-610, and AT-510 automatic potentiometric titrators. It transforms standalone titration workflows into fully unattended batch analysis platforms by automating sample positioning, reagent delivery coordination, electrode conditioning, and post-analysis waste handling. Based on the fundamental principle of potentiometric endpoint detection—where voltage potential across a reference–indicator electrode pair is monitored as titrant is incrementally added—the CHA-600 ensures high reproducibility across sequential determinations without operator intervention. Its modular architecture supports both routine QC laboratories requiring throughput scalability and regulated environments where procedural consistency and audit readiness are mandated.

Key Features

• Seamless interoperability with KEM AT-710, AT-610, and AT-510 titrators via standardized digital interface and synchronized command protocol
• Two configuration options: CHA-600-12 accommodates twelve 200 mL polypropylene or 300 mL tall-form beakers; CHA-600-18 supports eighteen 100 mL or 50 mL beakers for higher-density screening
• Programmable washing sequence—including customizable rinse volume, dwell time, and solvent selection—enabling method-specific electrode cleaning per sample or at user-defined intervals
• Pre-measured solvent dispensing and post-titration waste ejection functions reduce manual handling and improve volumetric accuracy in solvent-intensive methods (e.g., non-aqueous titrations)
• Optional exhaust hood integration for safe handling of volatile or hazardous solvents such as glacial acetic acid or pyridine, compliant with OSHA and local laboratory ventilation standards
• Optional thermostatic bath coupling enables temperature-controlled titrations between 5 °C and 40 °C, supporting applications requiring kinetic stabilization or thermosensitive endpoints (e.g., weak acid–weak base titrations)
• Independent wash reservoir with dedicated pump and valve manifold minimizes cross-contamination risk and extends electrode service life

Sample Compatibility & Compliance

The CHA-600 accepts standard laboratory glassware and chemically resistant polypropylene beakers, ensuring compatibility with acidic, basic, and organic media. Its mechanical design conforms to IEC 61000-6-2 (electromagnetic immunity) and IEC 61000-6-4 (emission) standards. When operated in conjunction with KEM’s FDA 21 CFR Part 11–enabled titrators (e.g., AT-710M), the integrated system supports electronic signatures, audit trails, and user-access controls required under GLP and GMP frameworks. All firmware updates and method files are timestamped and logged, satisfying traceability requirements outlined in ISO/IEC 17025:2017 Clause 7.7.

Software & Data Management

The CHA-600 operates under KEM’s proprietary Tiamo™ software environment (v3.0+), which provides centralized method development, sequence scheduling, and real-time status monitoring across multiple instruments. Each sample run generates a structured data file containing raw potential vs. volume curves, first-derivative plots, equivalence point calculations, and metadata (operator ID, timestamp, instrument serial number, environmental conditions). Data export formats include CSV, PDF reports, and XML for LIMS integration. Audit trail functionality records all parameter modifications, start/stop commands, and error events with immutable timestamps—fully compliant with ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available).

Applications

The CHA-600 supports a broad spectrum of standardized and in-house titration protocols, including but not limited to: acid–base titrations per ASTM D974 and ISO 3682; redox titrations (e.g., iodometry per USP ); precipitation titrations (e.g., chloride determination per ISO 9297); complexometric titrations (e.g., Ca²⁺/Mg²⁺ hardness per ISO 6059); and non-aqueous titrations (e.g., total acid number in lubricants per ASTM D664). Its reliability in multi-hour unattended operation makes it suitable for pharmaceutical stability studies, food quality control (e.g., titratable acidity in dairy products), and environmental testing (e.g., alkalinity profiling in wastewater).

FAQ

Can the CHA-600 operate independently without a KEM titrator?
No—it is a dedicated sample handling module and requires hardware-level synchronization with an AT-710, AT-610, or AT-510 titrator to execute titration sequences.
Is validation documentation available for regulated laboratories?
Yes—KEM provides IQ/OQ protocols, traceable calibration certificates for burette assemblies, and software verification reports aligned with GAMP 5 guidelines.
What maintenance is required for the wash station and fluid paths?
Daily rinsing with deionized water is recommended; quarterly inspection of tubing, valves, and stir bar alignment is advised per KEM Maintenance Schedule MS-CHA600 Rev. 2.1.
Does the CHA-600 support custom electrode types beyond standard pH and redox sensors?
Yes—any electrode with compatible BNC or DIN connectors and output signal within ±2000 mV range can be used, provided the host titrator supports its input configuration.
How is positional accuracy ensured during carousel rotation?
The indexing mechanism employs a high-resolution optical encoder and stepper motor with closed-loop feedback, achieving ±0.1° angular repeatability over 10,000 cycles.