GDW-501A Low-Temperature / High-Temperature Thermal Shock Bath by Langbo Instruments

Overview

The GDW-501A Low-Temperature / High-Temperature Thermal Shock Bath is a precision-engineered laboratory thermal conditioning system designed for rapid and stable temperature transitions across an extended operational range. Unlike standard circulating chillers or simple water baths, this unit integrates dual-mode refrigeration and high-efficiency electric heating to achieve controlled thermal shock cycling—enabling direct, repeatable transitions between −20 °C and +150 °C without manual intervention. Its core architecture employs a hermetic compressor-based refrigeration circuit coupled with PID-regulated immersion heaters and a high-turbulence circulation pump, ensuring uniform thermal distribution (±0.3 °C stability at setpoint) and minimal axial/radial gradients within the bath chamber. The system is purpose-built for applications requiring accelerated thermal stress testing, material compatibility validation under extreme conditions, and pre-conditioning of samples prior to analytical measurement.

Key Features

• Wide operational temperature span: −20 °C to +150 °C, verified per IEC 61000-4-29 for thermal stability under load
• Digital LED controller with programmable ramp-soak profiles (up to 10 segments), supporting time-based temperature sequencing
• Stainless steel 304 bath tank (capacity: 18 L nominal) with corrosion-resistant internal coating and integrated overflow drainage
• High-flow recirculation pump (≥12 L/min at 0.2 bar head) with adjustable flow rate and low-noise operation (<52 dB(A))
• Over-temperature, low-level fluid, and compressor overpressure protection circuits compliant with EN 61000-6-2 EMC requirements
• Front-panel USB port for firmware updates and configuration backup; optional RS485 Modbus RTU interface for LabVIEW or SCADA integration

Sample Compatibility & Compliance

The GDW-501A accommodates standard laboratory vessels—including glass beakers (up to Ø150 mm), metal sample holders, and sealed reaction tubes—within its open-bath geometry. It supports both aqueous and low-viscosity organic heat transfer fluids (e.g., ethylene glycol/water mixtures up to 50 % v/v). All wetted components meet USP Class VI biocompatibility criteria. The unit conforms to ISO/IEC 17025:2017 environmental conditioning requirements for accredited testing laboratories and is routinely deployed in GLP-compliant stability studies (ICH Q1A–Q1E). While not certified for hazardous location use (e.g., ATEX or UL Class I Div 1), it includes grounding continuity verification and meets CE marking directives for electrical safety (EN 61010-1) and electromagnetic compatibility.

Software & Data Management

The embedded controller logs real-time temperature, setpoint, and alarm status at user-defined intervals (1 s to 60 min), storing up to 30 days of data internally. Export is supported via CSV over USB mass storage mode. For networked environments, optional LangboLink™ software (Windows 10/11 compatible) enables remote monitoring, multi-unit synchronization, and audit-trail generation aligned with FDA 21 CFR Part 11 principles—including electronic signatures, user access levels (admin/operator), and immutable event logging. Data files include metadata such as operator ID, batch number, and calibration certificate reference—facilitating traceability in regulated QC/QA workflows.

Applications

• Thermal shock testing of polymers, adhesives, and composite laminates per ASTM D6930 and ISO 9022-3
• Pre-conditioning of sensors, optical components, and microelectromechanical systems (MEMS) prior to metrology
• Controlled cooling/heating cycles in enzymatic reaction kinetics studies and protein denaturation assays
• Calibration verification of infrared thermometers and contact probes across extended ranges
• Accelerated aging protocols for packaging materials and medical device housings (ISO 11607-1)
• Support equipment for rheometers, viscometers, and differential scanning calorimeters requiring external thermal control

FAQ

What heat transfer fluids are compatible with the GDW-501A?

Deionized water is recommended for operation between 5 °C and 95 °C. For sub-zero performance, a 40 % ethylene glycol/water mixture is validated down to −20 °C. Silicone oils are not supported due to viscosity and pump compatibility constraints.
Does the unit support external temperature feedback control?

Yes—the optional PT100 input port allows connection of an external probe for chamber or sample-block temperature feedback, enabling cascade control mode with ±0.1 °C setpoint accuracy.
Is calibration documentation provided with shipment?

Each unit ships with a factory calibration report (traceable to NIM, China) covering three points across the range: −20 °C, 25 °C, and 150 °C. Certificate of Conformance and calibration uncertainty values are included.
Can the GDW-501A operate continuously at 150 °C?

Continuous operation at maximum temperature is permitted for ≤8 hours per cycle, contingent upon ambient room temperature ≤25 °C and adequate ventilation (minimum 50 cm clearance on all sides). Extended dwell requires periodic compressor rest intervals per manufacturer’s maintenance schedule.
What is the mean time between failures (MTBF) for the refrigeration system?

Based on field data from 2021–2023 deployments, the compressor and refrigerant circuit exhibit an MTBF of 12,500 operating hours under standard laboratory duty cycles (≤6 hr/day, 5 days/week).