Techne LCB Series 5L/7L/12L Liquid Calibration Bath

Overview

The Techne LCB Series Liquid Calibration Bath is a precision-engineered, compact constant-temperature bath system designed for high-accuracy temperature calibration of contact sensors—including RTDs, thermistors, thermocouples, and liquid-in-glass thermometers—as well as for external temperature control of analytical instruments requiring stable thermal environments. Based on closed-loop refrigeration-heating thermodynamic architecture, the LCB series utilizes dual-mode PID control with independent refrigerant and heating circuits to achieve exceptional thermal uniformity and dynamic response across its full operational range. Its design conforms to ISO/IEC 17025 requirements for calibration laboratories and supports traceable temperature verification per ASTM E74, ISO 17034, and EURAMET cg-18 guidelines. The unit operates with either water, silicone oil, or low-viscosity heat-transfer fluids—enabling seamless transition between cryogenic and high-temperature applications without hardware modification.

Key Features

• Wide operational temperature range from −35 °C to +250 °C, enabled by integrated cooling coil (for connection to tap water or chiller) and high-efficiency resistive heating elements
• Temperature stability of ±0.005 °C at setpoint (measured over 2 hours in stabilized condition), verified using NIST-traceable reference probes
• Three standard bath volumes—5 L, 7 L, and 12 L—each with identical footprint (351 × 260 mm) and 140 × 140 mm open aperture for optimal probe access and instrument integration
• Full-perimeter and base insulation with vacuum-sealed panels minimizes ambient thermal drift and reduces energy consumption during extended operation
• High-flow external recirculation pump (flow rate adjustable up to 12 L/min) with pressure-regulated output for consistent thermal transfer to connected devices such as viscometers, spectrophotometers, refractometers, bioreactors, and reaction calorimeters
• Standard accessories include insulated lid, bridge mounting plate, sensor port inserts, and ergonomic lift handles—designed for safe handling and reduced evaporation loss

Sample Compatibility & Compliance

The LCB series accommodates immersion depths up to 300 mm (12 L model), supporting calibration of sensors up to 300 mm in length. Bath fluid compatibility includes deionized water, glycol-water mixtures, mineral oils, and silicone oils (viscosity ≤ 50 cSt at 25 °C). All models comply with IEC 61010-1:2010 for electrical safety in laboratory equipment and meet CE marking requirements for EMC and low-voltage directives. For GLP/GMP environments, optional audit-ready logging via TU-20 controller enables time-stamped temperature records compliant with FDA 21 CFR Part 11 when paired with Thermosoft software (free download available). Calibration certificates with uncertainty budgets are available upon request per ISO/IEC 17025 accreditation scope.

Software & Data Management

The TU-20 digital temperature controller features a 4-digit LED display, programmable ramp-soak profiles, and RS232/USB interface for remote operation. Thermosoft software—freely downloadable from Techne’s global support portal—provides real-time graphing, automated calibration sequence execution (e.g., fixed-point checks at 0 °C, 40 °C, 100 °C), and export of CSV-formatted data logs with metadata (operator ID, timestamp, ambient conditions). Data integrity safeguards include password-protected configuration changes, electronic signature prompts, and automatic backup of session history. Firmware updates are distributed through Techne’s secure customer portal and validated against IEC 62304 medical device software lifecycle standards.

Applications

• Primary and secondary temperature sensor calibration in metrology labs and accredited calibration service providers
• Thermal validation of process sensors used in pharmaceutical manufacturing (e.g., sterilization autoclaves, lyophilizers)
• Stabilized temperature source for viscosity measurements per ASTM D445 and ISO 3104
• Thermal conditioning of optical components during spectral analysis (UV-Vis, FTIR) to minimize thermal lensing effects
• Controlled-temperature environment for enzymatic assays, microbial growth studies, and accelerated stability testing (ICH Q1A)
• External temperature regulation of flow cells, HPLC columns, and electrochemical cells requiring precise thermal management

FAQ

What fluids are recommended for operation across the full −35 °C to +250 °C range?

For temperatures below 0 °C, use a 50/50 ethylene glycol–deionized water mixture; for >100 °C, select high-flashpoint silicone oil (e.g., Dow Corning 200 Fluid, 50 cSt). Avoid ethylene glycol above 120 °C due to degradation.
Can the LCB bath be integrated into a fully automated calibration station?

Yes—via RS232 or USB, the TU-20 controller supports SCPI command sets and is compatible with LabVIEW, Python (pySerial), and MET/CAL calibration software platforms.
Is external chiller connectivity mandatory to reach −35 °C?

Yes. The integrated cooling coil requires connection to a recirculating chiller capable of −40 °C outlet temperature and ≥2 bar pressure. Tap water cooling alone achieves only ~5 °C minimum.
How often does the system require recalibration for ISO/IEC 17025 compliance?

Annual verification using a certified reference thermometer is recommended; internal sensor drift is typically <±0.002 °C/year under normal operating conditions.
Does the LCB series support dry-well probe insertion?

No—it is a liquid-immersion bath only. For dry-well applications, Techne offers the DSC Series Dry Block Calibrators as a complementary product line.