Clarity Control Module LC UNI - WATREX PUMPS

Significance of the topic

High-performance liquid chromatography relies on precise pump control to achieve accurate flow rates and gradient profiles. The LC UNI Clarity Control Module for Watrex pumps enables seamless integration of Watrex SDS20 and SDS30 pumps into the DataApex Clarity chromatography platform. This universal driver simplifies setup and operation of diverse pump heads, enhances reproducibility, and ensures robust communication, making it invaluable for research, quality control, and industrial analysis.

Objectives and overview of the manual

This application note describes the installation, configuration, and use of the LC UNI module designed to control Watrex Deltachrom SDS20 and SDS30 pumps via RS-232 commands. It details hardware requirements, communication settings, profile selection, operation within Clarity, troubleshooting procedures, and guidelines for customizing or developing new pump profiles.

Methodology and instrumentation

Installation and Configuration

• Connect the pump to a PC COM port using DB9-RJ11 or DB9-DB9 straight cable.
• Power on the pump and select the correct pump head type (steel or plastic; 5, 10, or 40 mL) via front-panel RUN/STOP key during startup.
• Launch Clarity, open System Configuration, and add the LC UNI control module.
• In the UNI Pump Control Setup dialog specify COM port, communication parameters (baud rate, parity, data bits, stop bits) matching the pump, number of solvents, and load the appropriate Watrex profile (.UNI file).
• Assign solvents to an instrument tab in System Configuration.

Communication Parameters

• SDS020 and newer SDS030 pumps: 9600 baud; SDS030 older type: 2400 baud.
• No parity, 8 data bits, 1 stop bit.

Profiles and Customization

• Predefined profiles: Watrex_SDS020.uni, Watrex_SDS030_old.uni, Watrex_SDS030_new.uni.
• Profiles specify command structure, checksums, initialization, flow and pressure commands, error handling, and get-value polling.
• Customization allows editing of command‐response formats, conversion formulas, and adding new pump models via the UNI Pump Control Setup tabs (Command Format, Init, Set Pressure Limits, Set Flow, Error Status, Get Values).

Main results and discussion

The LC UNI driver achieves reliable bidirectional communication with Watrex pumps, enabling:

• Dynamic gradient control directly from Clarity Method Setup, with a spreadsheet-style table for time, solvent percentages, and total flow.
• Graphical display of solvent composition and flow profile, with adjustable standby and idle states to protect columns and prevent solvent waste.
• Real-time monitoring of individual solvent flows, total flow, and pressure in the Device Monitor window, with manual override (Set Flow, Hold/Resume, Modify Gradient) during runs.
• Robust error detection and handling, including automatic stop on overpressure or underpressure and configurable error response commands.

Field tests confirm stable operation, accurate flow delivery within pump specifications, and clear audit trails for compliance in regulated environments.

Benefits and practical applications

Key advantages include:

• Universal support for multiple pump models and head types without dedicated hardware modules.
• Unified control interface within Clarity, reducing operator training and software complexity.
• Customizable profiles facilitate integration of emerging pump technologies.
• Integrated pressure monitoring safeguards HPLC columns from damage.

This solution is ideal for analytical laboratories performing gradient separations in pharmaceuticals, environmental monitoring, food testing, and process control.

Future trends and opportunities

Advances in pump communication protocols (Ethernet, USB, wireless) may be incorporated into future UNI profiles. Software enhancements could include automated pump calibration routines, predictive maintenance alerts based on pressure trends, and cloud-enabled remote monitoring. Integration with multi-pump systems for seamless low- and high-pressure gradients will further expand application scope.

Conclusion

The LC UNI Clarity Control Module for Watrex pumps offers a flexible, reliable, and user-friendly solution for controlling Deltachrom SDS20 and SDS30 pumps. It streamlines installation and method setup, supports comprehensive gradient and pressure management, and provides tools for troubleshooting and customization. This module enhances the efficiency, reproducibility, and safety of liquid chromatography workflows.

Reference

DataApex Ltd. LC UNI – Watrex Pumps Clarity Control Module Manual, Code/Rev. M087/40G, October 24, 2022.