JWINS DC-3005A Precision Low-Temperature Circulating Bath

Overview

The JWINS DC-3005A is a high-precision, dual-mode circulating bath engineered for laboratory environments requiring stable thermal control across an extended range from −30 °C to +100 °C. It operates on the principle of closed-loop refrigeration combined with resistive heating, enabling accurate and reproducible temperature maintenance in both internal bath applications and external circulation setups. Unlike basic water baths, the DC-3005A integrates a hermetically sealed compressor-based cooling system and a high-efficiency heating element—allowing seamless transition between sub-zero and elevated temperatures without manual intervention. Its design conforms to JJF 1030–1998, the People’s Republic of China’s national metrological verification regulation for constant-temperature baths, ensuring traceable performance in calibration-sensitive workflows. The unit serves as both a self-contained temperature-controlled environment (e.g., for sample conditioning or viscometer calibration) and a remote thermal source—pumping conditioned fluid at 8–12 L/min to external apparatus such as spectrophotometer cells, reaction jackets, or material testing fixtures.

Key Features

• High-resolution digital display with 0.01 °C resolution and real-time temperature feedback
• Dual-circulation architecture: internal recirculation ensures uniform temperature distribution within the 5 L stainless steel bath; external circulation delivers consistent thermal transfer to auxiliary equipment
• Intelligent PID temperature controller with auto-tuning capability—adapts algorithm parameters based on thermal load, medium type (water, ethanol, silicone oil), and ambient conditions
• User-configurable over-temperature protection: alarm threshold and automatic power cutoff prevent thermal runaway during unattended operation
• Digital parameter lock function prevents unauthorized modification of setpoints, ramp rates, or safety limits—critical for GLP-compliant laboratories
• Corrosion-resistant construction: fully welded 304 stainless steel inner tank, powder-coated cold-rolled steel housing, and drain valve for easy maintenance
• Optional serial communication (RS232/RS485) enables integration into centralized lab management systems for remote monitoring and data logging

Sample Compatibility & Compliance

The DC-3005A accommodates a broad spectrum of thermal media—including deionized water, 30% ethylene glycol/water mixtures, and low-viscosity silicone oils—enabling compatibility with diverse experimental requirements across physical chemistry, polymer science, and pharmaceutical stability testing. Its ±0.05 °C temperature stability meets the precision thresholds required for ASTM D2857 (infrared spectroscopy sample conditioning), ISO 17025-accredited calibration labs, and USP <797> environmental monitoring protocols. While not certified to IEC 61000-6-3 or UL 61010-1 out-of-the-box, its electrical architecture adheres to general-purpose laboratory equipment safety principles, including reinforced insulation, grounded chassis, and thermal fusing in both compressor and heater circuits. All firmware and hardware revisions are documented per internal quality management procedures aligned with ISO 9001:2015.

Software & Data Management

The embedded microcontroller runs proprietary firmware supporting real-time temperature logging at user-defined intervals (1–60 s). When equipped with RS232/RS485, the device transmits ASCII-formatted telemetry—including setpoint, actual bath temperature, pump status, and fault codes—to third-party SCADA or LIMS platforms. No proprietary software installation is required; standard terminal emulators or Python-based scripts (e.g., PySerial) suffice for data acquisition. Audit trail functionality is limited to local event logging (e.g., “Over-temp alarm triggered at 2024-06-12T08:42:11”), but full 21 CFR Part 11 compliance—including electronic signatures and immutable records—requires integration with validated enterprise software layers. Firmware updates are performed via UART interface using manufacturer-provided utilities under controlled change management.

Applications

• Calibration of thermometers, RTDs, and thermocouples against NIST-traceable references
• Temperature-dependent viscosity measurements using rotational or capillary viscometers
• Controlled-rate cooling/heating of samples prior to DSC, TGA, or rheological analysis
• Stabilization of optical components in UV-Vis and FTIR spectrometers
• Thermal conditioning of biological reagents, enzyme assays, and cell culture media
• Supporting cold-finger condensation in distillation or extraction systems
• Environmental simulation for accelerated aging tests in materials science

FAQ

What is the maximum external load capacity when using the DC-3005A in external circulation mode?
The unit maintains ±0.05 °C stability with up to 2.5 kW thermal load when paired with a properly insulated external loop and compatible heat exchanger.
Can the DC-3005A operate continuously at −30 °C in high-humidity environments?
Yes—its condensate management system includes a dedicated evaporator drain path and anti-frost cycling logic, though ambient RH should remain below 80% to prevent ice accumulation on air intakes.
Is the stainless steel bath compatible with aggressive solvents such as acetone or chloroform?
No—the 304 SS interior is rated for aqueous and mild organic media only; halogenated or strongly acidic solvents require optional PTFE-coated accessory tanks.
Does the device support programmable temperature ramps?
Yes—up to 10 segment linear ramps can be defined via front-panel interface or serial command set, with ramp rates adjustable from 0.1 to 10 °C/min.
How often does the refrigerant require servicing?
Under normal operation and proper ventilation, the sealed R404A refrigeration circuit requires no maintenance for ≥8 years; annual visual inspection of condenser coil cleanliness is recommended.