Jihepu CJB-A-C Magnetic Stirrer

Overview

The Jihepu CJB-A-C Magnetic Stirrer is a precision-engineered, non-heating laboratory stirrer designed for reliable, low-maintenance mixing of aqueous and organic solutions in standard glassware. Unlike integrated hotplate-stirrers, this unit operates exclusively as a magnetic drive platform—eliminating thermal interference while enabling flexible integration with external heating systems such as oil baths, water baths, or heating mantles. Its core principle relies on rotating magnetic fields generated by a high-efficiency brushless DC motor to induce torque on PTFE- or glass-coated magnetic stir bars, ensuring consistent rotational coupling without mechanical contact. Engineered for long-term stability in QC labs, teaching laboratories, and R&D environments, the CJB-A-C delivers reproducible agitation across viscosity ranges typical of dilute to moderately viscous samples (e.g., buffer solutions, polymer precursors, cell culture media), with no risk of electromagnetic interference to adjacent instrumentation.

Key Features

• Brushless DC Motor Drive: Equipped with a certified PAPST series brushless DC motor—ensuring ultra-low acoustic noise (20,000 h MTBF) under continuous operation.
• Nanocomposite Stirring Surface: Circular top plate fabricated from a thermally stable, wear-resistant nanocomposite material offering superior magnetic flux transmission, chemical inertness against common solvents (e.g., ethanol, acetone, dilute acids/bases), and resistance to micro-scratching during routine cleaning.
• Ergonomic 30° Tilted Interface: Analog speed control knob positioned on a precisely angled front panel—optimized for both seated and standing operator postures, minimizing parallax error and improving tactile feedback during fine-speed adjustments.
• Robust Aluminum Housing: Anodized aluminum alloy chassis provides structural rigidity, passive heat dissipation, electrical insulation (IEC 61010-1 Class II), and corrosion resistance in ambient lab environments—including exposure to mild humidity and incidental reagent splashes.
• Variable-Speed Precision Control: Continuously adjustable speed range from 150 to 1800 rpm with linear response characteristics; maintains stable rotation even at sub-300 rpm for gentle suspension of sensitive biological samples or crystallization studies.
• Modular Integration Design: Flat, unobstructed surface allows seamless placement of external heating devices (e.g., circulating water baths, ceramic heating mantles) beneath reaction vessels—supporting ASTM E2913-compliant temperature-controlled mixing protocols when paired with validated external controllers.

Sample Compatibility & Compliance

The CJB-A-C supports standard borosilicate glass vessels (e.g., beakers, Erlenmeyer flasks, round-bottom flasks) up to 1000 mL volume, accommodating stir bars ranging from 10 mm to 40 mm in length. It is compatible with chemically resistant stir bars coated in PTFE, glass, or ETFE—suitable for pH 1–14 solutions, including saline buffers, enzymatic reaction mixtures, and organic solvent systems (e.g., THF, DCM, IPA). The device complies with IEC 61010-1:2010 for electrical safety in laboratory equipment and meets EMC requirements per CISPR 11 Group 1, Class B. While not intrinsically rated for hazardous locations, it is suitable for general-purpose use in ISO/IEC 17025-accredited testing laboratories where documented risk assessments confirm absence of explosive atmospheres or corrosive gas exposure.

Software & Data Management

This analog-controlled magnetic stirrer does not incorporate digital firmware, embedded software, or data logging capabilities. Its operational simplicity aligns with GLP/GMP Annex 11 principles for “low-risk” auxiliary equipment—requiring only periodic verification of speed accuracy (e.g., using a calibrated tachometer per SOP-LAB-027) and visual inspection of housing integrity. No electronic records, audit trails, or user authentication are applicable. Calibration documentation and maintenance logs may be maintained manually or within a LIMS using standardized templates aligned with ISO/IEC 17025 clause 6.4.2.

Applications

• Homogenization of calibration standards and reference solutions in analytical chemistry workflows
• Preparation of uniform suspensions for particle size analysis (e.g., prior to laser diffraction measurement)
• Mixing of reagent blends in spectrophotometric assay development (e.g., ELISA, colorimetric enzyme kinetics)
• Controlled agitation during titration setup and endpoint stabilization
• Cell culture media equilibration in non-sterile preparatory steps
• Supporting ASTM D445 (kinematic viscosity) sample conditioning when used with thermostatted baths

FAQ

Can the CJB-A-C be used with heating mantles or water baths?
Yes—the flat, non-heating nanocomposite surface is specifically engineered to accommodate external heating devices. Ensure thermal insulation between the stirrer base and heating source to prevent motor overheating.

Is grounding mandatory for safe operation?
Yes. The unit requires connection to a properly grounded AC outlet (IEC 61010-1 compliance). Failure to ground voids safety certification and increases electric shock hazard.

What is the recommended maintenance interval?
Visual inspection and speed verification should be performed quarterly; motor performance remains stable under normal use without scheduled lubrication or internal servicing.

Does this model support RS-232 or USB connectivity?
No. The CJB-A-C is an analog-only instrument with no digital interfaces, firmware, or remote control capability.

Can it handle viscous solutions like glycerol or polymer melts?
It is rated for up to 1000 mL of low-to-medium viscosity liquids (≤500 mPa·s at 25 °C). For higher-viscosity applications, a gear-driven overhead stirrer is recommended.