CZGY CJJ-843 High-Power Magnetic Stirrer

Overview

The CZGY CJJ-843 High-Power Magnetic Stirrer is an industrial-grade, non-heated magnetic stirring system engineered for consistent, high-torque mixing of low- to medium-viscosity aqueous and organic solutions in research, quality control, and production laboratories. Unlike standard benchtop stirrers, the CJJ-843 employs a robust permanent-magnet DC motor coupled with a reinforced ceramic-coated stirring platform—designed to sustain continuous operation at elevated rotational loads without thermal drift or mechanical fatigue. Its measurement principle relies on magnetic coupling between the rotating internal magnet assembly and a PTFE- or glass-coated stir bar placed within the vessel; torque transmission occurs without physical shaft penetration, eliminating seal wear and contamination risk. With a rated capacity of up to 30 L (using appropriately sized vessels and stir bars), it supports large-volume reagent preparation, buffer equilibration, dissolution testing, and pre-analytical sample homogenization under ISO/IEC 17025-compliant conditions.

Key Features

• High-torque 40 W permanent-magnet DC motor enabling stable rotation across the full 200–2000 rpm range—even with viscous or dense suspensions
• Ceramic-fused stainless steel platform (28 × 28 cm) resistant to chemical corrosion, thermal shock, and mechanical abrasion
• True stepless speed control via precision potentiometer—no gear switching or discrete speed steps
• No open flame, no audible motor noise, and zero electromagnetic interference with adjacent analytical instrumentation
• Designed for uninterrupted 8-hour duty cycles under ambient laboratory conditions (15–35 °C, ≤80% RH)
• Complies with IEC 61010-1 safety standards for laboratory electrical equipment; CE-marked for EU market access

Sample Compatibility & Compliance

The CJJ-843 accommodates standard laboratory glassware—including beakers (up to 5 L), tall-form cylinders, and jacketed reactors—when paired with appropriately dimensioned magnetic stir bars (e.g., 40–60 mm elliptical or cross-shaped bars for volumes >10 L). It is compatible with water, saline buffers, ethanol/water mixtures, dilute acids and bases (pH 2–12), and common organic solvents (e.g., acetone, THF, chloroform) provided the stir bar coating remains intact. While not certified for ATEX or IECEx hazardous-area use, its non-sparking motor design makes it suitable for general-purpose fume hood applications. The unit meets baseline requirements for Good Laboratory Practice (GLP) documentation when integrated into validated SOPs—particularly for dissolution uniformity testing (per USP ) and reagent batch homogenization where traceable mixing consistency is required.

Software & Data Management

As a standalone analog-controlled instrument, the CJJ-843 does not incorporate digital firmware, embedded software, or data logging capabilities. Speed setting is manually adjusted and visually confirmed via front-panel LED indicator (on/off only). For laboratories operating under FDA 21 CFR Part 11 or ISO 13485 quality systems, users may document operational parameters—including speed setting, duration, vessel type, and stir bar specification—in paper-based or electronic lab notebooks (ELN) as part of batch records. Calibration verification (e.g., tachometer-based speed validation) should be performed semiannually per internal metrology protocols. No firmware updates, cloud connectivity, or remote diagnostics are supported.

Applications

• Preparation of large-volume calibration standards and stock solutions (e.g., 20–30 L phosphate-buffered saline batches)
• Homogenization of cell culture media prior to filtration sterilization
• Dissolution testing of pharmaceutical tablets per USP apparatus II (paddle method) auxiliary mixing support
• Blending of polymer emulsions and colloidal suspensions in materials science labs
• Continuous agitation during titration endpoint stabilization or redox reaction monitoring
• Supporting ASTM D4097 (Standard Test Method for Determining the Stability of Emulsions) via controlled shear input

FAQ

Does the CJJ-843 include heating functionality?
No. This model is a non-heated magnetic stirrer. Temperature control requires external integration with a water bath, heating mantle, or hotplate-stirrer combination.
What is the recommended stir bar size for 30 L mixing?
A 60 mm cross-shaped or dual-magnet stir bar with PTFE/glass coating is advised; ensure submersion depth exceeds 1/3 of vessel height and clearance from bottom ≥15 mm.
Can the unit operate continuously for extended periods?
Yes—rated for 8-hour uninterrupted operation at speeds ≥800 rpm. For longer durations, periodic 15-minute cooldown intervals are recommended to maintain motor longevity.
Is speed accuracy traceable to national standards?
Speed indication is analog and non-calibrated. For traceable verification, users must employ an external optical tachometer calibrated per ISO/IEC 17025-accredited procedures.
What maintenance is required?
Wipe platform surface after each use with isopropyl alcohol; inspect stir bar coating integrity monthly; replace fuse (250 V, 1 A slow-blow) if power fails—no internal servicing required.