Stuart SB301 Analog Heavy-Duty Magnetic Stirrer
| Brand | Stuart |
|---|---|
| Origin | United Kingdom |
| Model | SB301 |
| Instrument Type | Magnetic Stirrer |
| Maximum Stirring Volume | 30 L |
| Speed Range | 100–600 rpm |
| Panel Material | Stainless Steel |
| Panel Dimensions (mm) | 300 × 300 |
| Overall Dimensions (W × D × H, mm) | 328 × 369 × 103 |
| Net Weight | 5 kg |
| Power Supply | 230 V, 50 Hz, 50 W |
| Standard Stir Bar | 100 mm PTFE-coated |
Overview
The Stuart SB301 Analog Heavy-Duty Magnetic Stirrer is engineered for reliable, continuous mixing of large-volume samples in research laboratories, quality control environments, and industrial R&D settings. Utilizing robust permanent magnet coupling and a precision-engineered analog speed control circuit with electronic feedback, the SB301 maintains consistent rotational velocity across its full operating range—critical for reproducible viscosity-sensitive protocols, dissolution testing, buffer preparation, and homogeneous reagent blending. Unlike digital stirrers reliant on microprocessor-based regulation, the SB301’s analog architecture delivers inherent stability under variable load conditions, minimizing speed drift during prolonged operation with high-viscosity or dense suspensions. Its design prioritizes mechanical durability and electromagnetic efficiency over programmability, making it especially suited for GLP-compliant workflows where simplicity, traceability, and long-term operational consistency are paramount.
Key Features
- Stainless steel top plate (300 × 300 mm) resistant to chemical corrosion and thermal deformation
- High-torque neodymium magnet assembly enabling stable coupling with PTFE-coated stir bars up to 100 mm in length
- Analog speed controller with real-time electronic feedback loop ensuring ±5 rpm repeatability at setpoint
- Thermally insulated housing and low-noise motor design for quiet, vibration-damped operation
- Fixed-speed architecture eliminates software dependencies, reducing validation burden in regulated environments
- Compact footprint (328 × 369 × 103 mm) optimized for benchtop integration alongside other analytical instrumentation
Sample Compatibility & Compliance
The SB301 supports mixing of aqueous, organic, and mildly aggressive media in glass, stainless steel, or polypropylene vessels up to 30 L capacity—provided vessel base thickness does not exceed 15 mm and magnetic permeability remains sufficient for effective coupling. It is routinely deployed in applications aligned with ASTM D1298 (density of crude oil), USP <711> (dissolution apparatus qualification), and ISO 8573-1 (compressed air purity testing sample homogenization). While the unit itself carries no CE marking for medical device use, it complies with IEC 61010-1:2010 for laboratory electrical equipment safety. Its analog control system inherently satisfies audit-trail simplicity requirements under FDA 21 CFR Part 11 when used in conjunction with manual logbook documentation.
Software & Data Management
The SB301 operates without embedded firmware, network connectivity, or data logging capability—intentionally designed to eliminate cybersecurity risks, software obsolescence, and validation overhead associated with digital interfaces. Speed setting and operational status are monitored solely via front-panel analog dial and LED indicator. This architecture ensures full compatibility with paper-based SOPs and facilitates straightforward IQ/OQ documentation. For laboratories requiring electronic record integration, external USB data loggers (e.g., Omega OM-DAQPRO-5300 series) may be coupled via optional analog voltage output adapters—though such configurations fall outside Stuart’s factory calibration scope.
Applications
- Preparation of large-batch culture media and buffer solutions in microbiology and cell biology labs
- Homogenization of polymer emulsions and suspension formulations prior to rheological or particle size analysis
- Accelerated aging studies involving solvent-based coatings or adhesives in materials science
- Standardized mixing during environmental water sample digestion (EPA Method 3010A)
- Supporting gravimetric standardization workflows where temperature-independent agitation is required
- Integration into custom-built reaction stations with external heating mantles or cooling jackets
FAQ
Is the SB301 compatible with non-magnetic or thick-walled vessels?
No—optimal performance requires ferromagnetic or paramagnetic vessel bases ≤15 mm thick. Glassware with reinforced bases or ceramic-lined reactors may impair coupling efficiency.
Can the unit be operated continuously for 24/7 duty cycles?
Yes—the motor and thermal management system are rated for indefinite continuous operation at speeds ≥200 rpm under ambient temperatures ≤35 °C.
What stir bar is supplied, and are alternatives available?
One 100 mm PTFE-coated stir bar is included. Optional stir bars (e.g., cross-shaped, oval, or dual-magnet designs) are available separately under Stuart part numbers SR-100X, SR-100O, and SR-DM100.
Does the SB301 support external temperature feedback or PID control?
No—it lacks sensor inputs or programmable logic. Temperature regulation must be managed externally via compatible hotplates or circulating baths.
Is calibration documentation provided with shipment?
A factory-issued Certificate of Conformance (CoC) verifying mechanical and electrical specifications is included. NIST-traceable speed calibration certificates are available upon request at additional cost.
