Hengping DC-3015 Digital Low-Temperature Constant-Temperature Bath Circulator

Overview

The Hengping DC-3015 Digital Low-Temperature Constant-Temperature Bath Circulator is a precision-engineered thermal management system designed for laboratory and industrial applications requiring stable, uniform, and programmable temperature control across a wide operational range (-40 °C to +100 °C). It operates on the principle of closed-loop liquid circulation thermoregulation, utilizing a microprocessor-controlled PID algorithm with auto-tuning capability to maintain high thermal fidelity. The unit integrates a high-efficiency single-stage compressor refrigeration system—optimized for sub-zero performance without CFC refrigerants—and a dual-mode circulation architecture enabling both internal bath temperature stabilization and external secondary temperature field establishment via pumped fluid transfer. Its stainless steel (SUS304) bath chamber, rigid insulated housing with polyurethane foam encapsulation, and low-heat-generation centrifugal pump collectively ensure minimal thermal drift, rapid equilibration, and long-term operational stability under continuous duty.

Key Features

• Precision temperature control with ±0.05 °C stability at 25 °C (verified in water or ethanol), achieved via Pt100 sensor feedback and self-tuning PID regulation
• Dual-circulation capability: internal recirculation for bath homogeneity; external port for closed-loop temperature control of peripheral equipment (e.g., reactors, spectrometers, rheometers)
• 10 L/min flow rate centrifugal pump with non-self-heating design—eliminates parasitic thermal load on the bath medium
• Robust mechanical construction: 304 stainless steel inner tank and top plate; electrostatically sprayed anti-aging powder-coated outer casing; R-cornered ergonomic front panel for operator safety
• Comprehensive safety architecture: dry-run protection for heater, over-temperature/under-temperature alarm and cutoff, compressor overheat and overcurrent protection, open-circuit sensor detection, and automatic power recovery after interruption
• Modular serviceability: removable front grille for condenser cleaning; foldable side handles for safe manual relocation; optional heavy-duty locking casters for larger units

Sample Compatibility & Compliance

The DC-3015 accommodates a broad spectrum of sample configurations and experimental setups. Internally, it supports direct immersion of vessels up to 215 × 175 × 200 mm (L × W × D) within its 15 L working volume. Externally, it interfaces with auxiliary systems—including rotary evaporators, viscometers, ICP-MS chillers, NMR probe coolers, and chemical synthesis reactors—via standardized 1/4″ BSP or G1/4″ threaded fluid ports. The bath is compatible with aqueous, ethylene glycol–water, and ethanol–water mixtures as heat-transfer media, selected per application-specific freezing point and viscosity requirements. While not certified to ISO/IEC 17025 or GLP as a standalone measuring instrument, its temperature control performance meets the repeatability and stability criteria referenced in ASTM E29–23 (Standard Practice for Using Significant Digits), ISO 17025 Clause 7.8.3 (uncertainty estimation for controlled environments), and USP (Thermal Analysis Apparatus Qualification). All electrical components comply with IEC 61010-1:2010 for laboratory equipment safety.

Software & Data Management

The DC-3015 features an embedded digital controller with dual-display interface—simultaneously showing setpoint and real-time measured temperature—with 0.1 °C resolution. Optional communication modules (RS232 or RS485) support Modbus RTU protocol for integration into centralized lab automation platforms (e.g., LabVIEW, DeltaV, or custom SCADA). When equipped with the optional multi-segment programming module, users can define up to 30 temperature–time ramp/soak profiles for unattended operation. Data logging is supported via external PC connection, enabling timestamped acquisition of temperature traces for audit trails. Though the base unit does not include FDA 21 CFR Part 11-compliant electronic signatures or audit trail functionality, the optional communication interface allows third-party software to implement compliant data capture when deployed in regulated GMP/GLP environments—subject to site-specific validation protocols.

Applications

This circulator serves as a primary thermal source in diverse scientific and industrial domains. In analytical chemistry, it provides precise coolant supply for CCD detectors, AAS flame atomizers, and GC oven precooling stages. In materials science, it stabilizes sample stages during XRD, SEM/TEM cryo-transfer, and thin-film deposition processes. In biotechnology, it maintains constant temperature for enzyme kinetics assays, cell culture incubator pre-chilling, and PCR thermal cycler calibration. In physical chemistry, it enables controlled cooling of reaction mixtures in automated synthesizers, supports solvent removal in rotary evaporation (typically paired with vacuum controllers), and regulates condenser jackets in reflux and extraction systems. Its dual-circulation design also facilitates temperature synchronization across distributed instrumentation—such as coupling multiple rheometers or synchronizing laser cavity cooling with optical table thermal compensation.

FAQ

What temperature media are recommended for operation below 0 °C?

Ethanol–water (e.g., 30% v/v ethanol) or ethylene glycol–water (e.g., 40% v/v) solutions are standard. Viscosity and freezing point must be verified against target operating temperature.

Can the DC-3015 control external equipment temperature directly?

Yes—when fitted with the optional extended Pt100 external sensor and configured in “external temperature” mode, the unit regulates the secondary system’s temperature via feedback from that sensor, maintaining the same ±0.05 °C stability specification.

Is the bath suitable for oil-based heating above 100 °C?

No—the DC series is rated to +100 °C maximum. For higher-temperature applications (e.g., 150–300 °C), refer to Hengping’s CH-series super-constant-temperature oil baths, which feature sealed internal circulation only.

What maintenance intervals are recommended for optimal performance?

Condenser grille cleaning every 3 months (or more frequently in dusty environments); annual verification of Pt100 calibration traceability; biannual inspection of pump seal integrity and refrigerant pressure levels.

Does the unit support remote monitoring via Ethernet or Wi-Fi?

Not natively—the standard communication options are RS232/RS485. Ethernet or Wi-Fi connectivity requires an external protocol converter or gateway device compatible with Modbus RTU.