CZGY HJ-4B Dual Digital Display Magnetic Stirrer with Independent Temperature Control

Overview

The CZGY HJ-4B Dual Digital Display Magnetic Stirrer is an engineered solution for parallel, temperature-controlled mixing in research laboratories, quality control environments, and teaching facilities. Designed around the principle of magnetic coupling—where a rotating permanent magnet beneath a non-magnetic plate induces rotation of a PTFE-coated stir bar immersed in the sample—the HJ-4B delivers precise, contactless agitation across four independent stations. Each station integrates a dedicated DC motor drive and a resistive heating element embedded within a 12 cm stainless steel heating plate, enabling simultaneous stirring and thermostatic control from ambient +5°C up to 100°C. The dual digital display provides real-time, separate readouts for rotational speed (rpm) and actual plate temperature (°C), ensuring operational transparency and repeatability. Its full stainless steel housing enhances corrosion resistance, mechanical stability, and compliance with routine lab cleaning protocols under GLP-aligned workflows.

Key Features

• Four independent stirring/heating stations with fully decoupled speed and temperature control
• Dual LED digital displays per station—separate rpm and temperature readouts for immediate process verification
• Speed regulation from 200 to 2000 rpm with smooth analog adjustment and high-speed stability at elevated setpoints
• Precise temperature control via PID algorithm; resolution of 1°C, accuracy ±2°C across 25–100°C range
• 25 W brushless DC motors per station ensure low noise, minimal heat generation, and extended service life
• 200 W ceramic-heated stainless steel plates (12 cm diameter each) provide uniform thermal distribution and rapid warm-up
• Full 304 stainless steel construction—including base, housing, and heating platforms—for chemical resistance and ease of decontamination
• Overheat protection circuitry automatically disables heating if surface temperature exceeds 110°C

Sample Compatibility & Compliance

The HJ-4B accommodates standard laboratory glassware including beakers (50–1000 mL), Erlenmeyer flasks, and round-bottom vessels placed directly on the heating plates. It supports aqueous, organic, and mildly corrosive solutions when used with chemically inert stir bars (e.g., PTFE- or glass-coated). The device meets IEC 61010-1:2010 safety requirements for electrical equipment used in laboratory environments. While not certified for hazardous area use (e.g., ATEX/IECEx), its design adheres to general-purpose lab safety standards applicable to non-explosive atmospheres. For regulated environments, the instrument’s stable thermal and rotational performance supports method validation per ASTM D1896 (viscosity measurement preparation) and ISO 787-17 (dispersion testing of pigments and fillers).

Software & Data Management

The HJ-4B operates as a standalone analog-digital hybrid instrument without onboard data logging or PC connectivity. All parameter adjustments are made manually via front-panel rotary dials with tactile feedback. However, its consistent output characteristics make it suitable for integration into documented procedures requiring manual recording—particularly in ISO/IEC 17025-accredited testing labs where operator-recorded setpoints and observed values are captured in paper-based or LIMS-linked batch records. The dual-display architecture minimizes transcription errors during multi-step protocols, supporting audit readiness for GLP and GMP-aligned operations where traceability of mixing conditions (speed, duration, temperature) is essential for assay reproducibility.

Applications

• Preparation of homogeneous buffer solutions, calibration standards, and reagent blends in analytical chemistry labs
• Accelerated dissolution testing of pharmaceutical excipients and active ingredients under controlled thermal conditions
• Supporting enzymatic reaction kinetics studies requiring constant agitation at defined temperatures
• Cell culture media equilibration and pH adjustment prior to sterile filtration
• Sample homogenization in environmental testing (e.g., soil leachate extraction, water hardness titration prep)
• Teaching laboratory demonstrations of thermally coupled mixing dynamics in undergraduate physical chemistry courses

FAQ

Can the HJ-4B be used with sealed vessels or pressure-rated reactors?
No—this unit is designed exclusively for open-vessel applications using standard lab glassware. It lacks pressure containment features or specialized sealing interfaces.
Is external temperature probe input supported for solution-phase monitoring?
No—the built-in sensor measures only the heating plate surface temperature. For accurate solution temperature tracking, an external calibrated thermometer or PT100 probe must be used independently.
What maintenance is required to ensure long-term speed and temperature accuracy?
Routine cleaning of the stainless steel plates with ethanol or mild detergent; periodic inspection of stir bar integrity; and verification of rpm display against a handheld tachometer every 6 months in regulated settings.
Does the unit comply with FDA 21 CFR Part 11 requirements?
No—it has no electronic audit trail, user authentication, or electronic signature capability. It is intended for use in non-electronic record environments or as part of manually documented processes.