CZGY CJ-H20 Magnetic Stirrer

Overview

The CZGY CJ-H20 Magnetic Stirrer is a compact, benchtop laboratory instrument engineered for precise and reliable agitation of liquid samples in beakers, flasks, and other standard glassware. It operates on the principle of magnetic coupling: a rotating permanent magnet or electromagnetic drive beneath the non-magnetic, stainless-steel plate induces synchronous rotation of a PTFE- or glass-coated magnetic stir bar immersed in the sample. This contactless drive mechanism eliminates mechanical shaft seals, ensuring zero contamination risk, silent operation, and no vibration transmission to sensitive setups—critical for analytical workflows requiring stable thermal or optical conditions. Designed for routine mixing in academic teaching labs, environmental testing facilities, pharmaceutical QC units, and industrial R&D environments, the CJ-H20 delivers consistent torque across its full speed range without load-induced stall, supporting reproducible homogenization, dissolution, and reagent blending tasks.

Key Features

• Stainless steel working surface (160 × 160 mm) resistant to corrosion from acids, bases, and organic solvents—ensuring long-term dimensional stability and ease of decontamination.
• Stepless electronic speed control (0–2500 rpm) with smooth ramp-up response; prevents stir bar “jumping” by enforcing gradual acceleration from low to high setpoints.
• Low-power 8 W DC motor with optimized thermal management—enables continuous operation at medium speeds (≤1500 rpm) for up to 8 hours, and at high speeds (≥2000 rpm) for 4 hours under ambient conditions (23 ± 2 °C).
• No integrated heating or temperature regulation—intentionally designed as a dedicated stirring-only platform to avoid thermal drift in applications requiring external temperature control (e.g., water baths, chillers, or hotplates).
• Compliance-ready electrical architecture: grounded chassis, IEC 61010-1 Class I safety rating, and built-in overcurrent protection—meets baseline requirements for GLP-compliant lab infrastructure.

Sample Compatibility & Compliance

The CJ-H20 accommodates standard laboratory vessels up to 2 L capacity, including borosilicate glass beakers (≥50 mL), Erlenmeyer flasks, and cylindrical reaction tubes. Optimal performance requires flat-bottomed containers and appropriately sized stir bars (typically 20–40 mm length for 1–2 L volumes). The unit conforms to GB/T 29791.2–2013 (Chinese national standard for laboratory stirrers) and aligns with general-purpose safety expectations outlined in ISO/IEC 17025:2017 Clause 6.4 (equipment suitability verification). While not certified to UL or CE for export markets, its grounding terminal, insulated housing, and voltage tolerance (220 V ±10 %) support safe deployment in laboratories adhering to local electrical codes.

Software & Data Management

As a manually operated analog device, the CJ-H20 does not incorporate digital interfaces, firmware, or data logging capabilities. Speed selection is performed via front-panel rotary potentiometer with LED power indicator only. This design prioritizes operational simplicity, electromagnetic compatibility (EMC), and immunity to software obsolescence—making it suitable for regulated environments where audit trails are maintained externally (e.g., paper-based logbooks per FDA 21 CFR Part 11 Annex A guidance for non-computerized systems). Users are advised to record speed settings, duration, and vessel configuration in their experiment notebooks for full traceability.

Applications

• Standard solution preparation in chemistry and biology teaching labs (e.g., buffer dilution, titrant mixing).
• Homogenization of suspended particulates during environmental water analysis (e.g., turbidity standards, sediment resuspension).
• Accelerated dissolution testing in pharmaceutical quality control per USP , where consistent agitation is required without heat input.
• Pre-analytical sample conditioning prior to ICP-OES, HPLC, or spectrophotometric measurement—minimizing settling artifacts.
• Supporting multi-step synthesis protocols in organic chemistry labs where inert-atmosphere reactors require external stirring synchronization.

FAQ

Does the CJ-H20 include a heating function?
No. The CJ-H20 is a non-heating magnetic stirrer. Temperature control must be achieved externally using water baths, cooling jackets, or separate hotplates.
What is the recommended stir bar size for 2 L beakers?
A 35–40 mm PTFE-coated stir bar with centered magnetic dipole alignment ensures optimal coupling and vortex formation at speeds above 800 rpm.
Can the unit operate continuously at 2500 rpm?
Continuous high-speed operation is rated for 4 hours maximum. For extended use, maintain speeds ≤1500 rpm to ensure thermal stability and bearing longevity.
Is the stainless steel plate removable for cleaning?
No—the plate is permanently bonded to the chassis. Clean using lint-free cloths dampened with 70 % ethanol or mild detergent; never immerse the base unit in liquid.
What safety certifications does this model hold?
It complies with GB/T 29791.2–2013 and incorporates protective grounding per IEC 61010-1. CE or UL certification is not provided; users must verify local regulatory acceptance prior to installation.