LAUDA Alpha RA 12 External Circulation Refrigerated/Heating Bath –25 to 100 °C, ±0.05 °C Stability

Overview

The LAUDA Alpha RA 12 is a precision-engineered refrigerated/heating circulating bath designed for demanding laboratory temperature control applications requiring stable thermal environments across an extended range of –25 °C to 100 °C. Based on LAUDA’s proven Alpha platform, the RA 12 integrates a hermetically sealed compressor-based cooling system with a high-efficiency resistive heating element and a continuously controlled electronic thermostat—enabling accurate, reproducible, and energy-optimized thermal regulation. Its operation relies on forced convection via an integrated circulation pump, allowing both internal bath homogenization and external temperature conditioning of analytical instruments (e.g., spectrophotometers, viscometers, calorimeters), reactors, or sample holders. The unit complies with IEC 61010-1 safety standards for laboratory equipment and incorporates fail-safe thermal protection mechanisms—including overtemperature cutoff, low-bath-level detection, and flow monitoring—to ensure operational integrity under continuous use.

Key Features

• Wide operational temperature span from –25 °C to 100 °C with ±0.05 °C stability at setpoint—achievable using water, aqueous glycol mixtures, or ethanol as heat transfer fluids;
• Intelligent compressor management system that activates cooling only when required, minimizing mechanical wear and reducing long-term energy consumption;
• Stainless steel bath vessel (300 × 203 × 160 mm) with 14.5 L usable volume and integrated lid to minimize evaporation and improve thermal uniformity;
• Front-accessible condenser grille—tool-free removal enables routine maintenance without service interruption;
• Three-button intuitive interface with single-line LED display showing either actual or set temperature; menu-driven navigation supports rapid configuration;
• Integrated circulation pump delivering up to 15 L/min at 0.2 bar pressure, compatible with external loops via standardized silicone tubing connections;
• Ethernet port standard-equipped for remote monitoring and integration into centralized lab infrastructure (e.g., SCADA or LIMS); optional accessories include flow meters and speed-controlled pumps;
• Compliant with EU Regulation No. 517/2014 on fluorinated greenhouse gases—uses R-134a (GWP = 1430) in a fully sealed refrigeration circuit with verified charge integrity.

Sample Compatibility & Compliance

The RA 12 is validated for use with non-flammable heat transfer media only—primarily deionized water, water–ethylene glycol (up to 50% v/v), or ethanol. It is not rated for flammable solvents, oils, or corrosive liquids. All wetted components—including the bath chamber, pump housing, and fluid pathways—are constructed from electropolished stainless steel (AISI 316) and EPDM-sealed fittings to ensure chemical resistance and long-term reliability. The device meets CE marking requirements under the Low Voltage Directive (2014/35/EU) and EMC Directive (2014/30/EU). While not inherently 21 CFR Part 11 compliant, its digital logging capability (via optional software) supports audit-ready data capture when deployed in GLP- or GMP-aligned workflows involving temperature-critical sample preparation, dissolution testing, or stability studies per USP & ISO 8573-1.

Software & Data Management

The RA 12 features embedded firmware supporting real-time temperature logging at user-defined intervals (1–60 s). Data export is enabled via USB or Ethernet connection using LAUDA’s proprietary PC software suite (AlphaControl), which provides graphical trend analysis, alarm history review, and configurable export to CSV or PDF formats. For integration into automated laboratories, the unit supports Modbus TCP protocol for bidirectional communication with PLCs or building management systems. Optional firmware upgrades enable password-protected user levels, electronic signature support, and time-stamped event logs—including compressor activation cycles, temperature deviations exceeding ±0.1 °C, and fault conditions—facilitating compliance with ISO/IEC 17025 documentation requirements.

Applications

• Chemical synthesis and reaction calorimetry where precise exotherm control between –20 °C and 80 °C is required;
• Pharmaceutical QC testing—including dissolution apparatus calibration (USP ), tablet coating stability assessment, and accelerated aging protocols;
• Biotechnology applications such as enzyme activity assays, cell culture incubator pre-conditioning, and ELISA plate thermal equilibration;
• Materials science characterization—including battery electrolyte viscosity profiling, polymer melt index determination, and thin-film deposition substrate temperature stabilization;
• Electronics reliability testing—thermal cycling of PCB assemblies, semiconductor wafer chuck conditioning, and laser diode thermal sink control;
• Calibration of temperature-sensitive sensors (RTDs, thermistors, IR cameras) across multi-point traceable ranges.

FAQ

What heat transfer fluids are approved for use with the RA 12?

Deionized water, water–ethylene glycol mixtures (≤50% v/v), and ethanol are certified for operation. Mineral oil, silicone oil, acetone, and other flammable or highly volatile solvents are strictly prohibited.
Can the RA 12 be used for external circulation with third-party instruments?

Yes—the unit includes dedicated inlet/outlet ports with quick-connect fittings and ships with silicone tubing and pump adapters compatible with standard 10–12 mm OD connections.
Is remote monitoring supported out-of-the-box?

Yes—Ethernet connectivity is standard, and the built-in web server allows real-time parameter viewing and basic setpoint adjustment via any modern browser.
How does the intelligent compressor control reduce operating costs?

The controller continuously evaluates thermal load and modulates compressor duty cycle—not runtime—resulting in up to 35% lower average power draw versus fixed-speed alternatives during partial-load conditions.
Does the RA 12 meet environmental regulations for refrigerant handling?

Yes—it uses R-134a within a fully sealed, leak-tested circuit conforming to EN 378-2 and EU F-Gas Regulation (517/2014), including mandatory refrigerant charge labeling and service port design.