The Great Wall HWCL-1 Circulating Magnetic Hotplate Stirrer

Overview

The Great Wall HWCL-1 Circulating Magnetic Hotplate Stirrer is an integrated thermal-magnetic laboratory instrument engineered for precise temperature control and uniform mechanical agitation in open-vessel chemical synthesis, dissolution testing, and sample preparation workflows. Unlike conventional hotplate stirrers, the HWCL-1 employs a circulating oil or water bath architecture—featuring a thermostatically regulated heating reservoir that fully envelops reaction vessels (e.g., beakers, Erlenmeyer flasks) to ensure radial and axial thermal homogeneity. Its core operation combines two synchronized functions: (1) resistive heating of the bath medium via a 300 W embedded heater, regulated by a PID feedback loop for stable setpoint maintenance within ±1°C; and (2) magnetic stirring of both the bath fluid and the sample vessel’s contents using a brushless DC motor-driven rotating magnet assembly. This dual-action design eliminates thermal stratification and promotes consistent heat transfer across the vessel wall, critical for temperature-sensitive reactions, viscosity-dependent mixing, and reproducible kinetic studies.

Key Features

• Brushless DC motor drive ensures low electromagnetic interference, extended service life, and silent, maintenance-free operation under continuous load.
• High-temperature resistant permanent magnet system rated for uninterrupted operation up to 200°C without demagnetization—validated per IEC 60079-0 thermal endurance protocols.
• PID temperature controller with LED digital display and keypad interface enables precise setpoint entry (0.1°C resolution) and real-time monitoring of bath temperature.
• Dual-mode thermal operation: optimized for water baths (ambient +5°C to 95°C) and high-temperature oil baths (ambient +5°C to 200°C), supporting ASTM D2161 and ISO 3104 viscosity calibration procedures.
• Integrated safety architecture includes overcurrent protection, ground-fault detection, and independent overtemperature cutoff—compliant with IEC 61010-1 Edition 3 for laboratory electrical equipment.
• Compact footprint (190 × 200 × 490 mm) and lightweight construction (4 kg net) facilitate benchtop deployment in fume hoods, glove boxes, or shared analytical workstations.

Sample Compatibility & Compliance

The HWCL-1 accommodates standard laboratory glassware up to 500 mL capacity—including borosilicate beakers, round-bottom flasks, and crystallization dishes—when placed within its 1.5 L cylindrical bath chamber (Ø145 × 104 mm). Its open-bath configuration supports direct visual monitoring and easy access for sampling or reagent addition. The instrument meets essential safety and performance benchmarks for general-purpose lab use: it conforms to IEC 61010-1:2010 for electrical safety in measurement, control, and laboratory equipment; carries CE marking for EMC Directive 2014/30/EU and Low Voltage Directive 2014/35/EU; and is designed to support GLP-compliant workflows through traceable temperature setpoints and repeatable rotational output. While not certified for hazardous area use (ATEX/IECEx), its grounded chassis and isolation circuitry minimize risk in non-explosive environments.

Software & Data Management

The HWCL-1 operates as a standalone analog-digital hybrid device with no embedded firmware or network connectivity. All operational parameters—including temperature setpoint, actual bath temperature, and stirring speed—are displayed locally via a high-contrast LED panel. No external software, drivers, or cloud integration are required or supported. For laboratories requiring audit trails, users may document setpoints and observed values manually or integrate the unit into validated environmental monitoring systems via external PT100 probe inputs (optional accessory). The absence of programmable logic or data logging aligns with FDA 21 CFR Part 11 “non-electronic record” classification—making it suitable for QC labs where manual logbooks satisfy regulatory documentation requirements.

Applications

• Controlled-temperature synthesis of organometallic complexes requiring sustained heating above 100°C under inert atmosphere.
• Dissolution testing of pharmaceutical tablets per USP , where uniform bath temperature and gentle agitation prevent particle settling or localized overheating.
• Preparation of polymer solutions and colloidal dispersions demanding shear-controlled mixing at elevated temperatures.
• Calibration of viscometers and rheometers using standardized silicone oils across defined thermal gradients.
• Standardization of reference materials in metrology labs, where thermal stability and repeatability are prerequisites for uncertainty budgeting.
• Teaching laboratories performing Arrhenius kinetics experiments, leveraging its intuitive interface and robust thermal response for undergraduate instruction.

FAQ

What is the maximum recommended operating temperature for water versus oil media?

Water baths are rated for ambient +5°C to 95°C; oil baths (e.g., silicone or mineral oil) support ambient +5°C to 200°C. Exceeding 95°C with water risks boiling, vapor lock, and pressure buildup.
Does the unit include a temperature probe for external vessel monitoring?

No—the HWCL-1 measures bath temperature only. For internal sample temperature tracking, users must employ an independent calibrated probe inserted into the reaction vessel.
Can the stirring speed and temperature be controlled independently?

Yes. Speed adjustment uses a dedicated rotary knob (0–2000 rpm), while temperature is set separately via keypad—enabling decoupled optimization of shear rate and thermal profile.
Is the bath vessel removable for cleaning or replacement?

Yes. The stainless steel bath insert is mechanically secured and can be lifted out without tools for descaling or solvent rinsing.
What certifications does this instrument hold for international shipment?

It carries CE marking (EMC and LVD directives), RoHS 2011/65/EU compliance, and factory-issued Declaration of Conformity—sufficient for customs clearance in EU, UK, Canada, and Australia.