Stuart UC152/US152 Heated Magnetic Stirrer

Overview

The Stuart UC152 and US152 Heated Magnetic Stirrers are precision-engineered laboratory instruments designed for reliable, reproducible heating and stirring of liquid samples across research, quality control, and teaching laboratories. Based on the fundamental principle of magnetic coupling—where a rotating permanent magnet beneath the heating plate induces rotation in a PTFE-coated stir bar immersed in the sample—these units deliver consistent torque transfer and thermal uniformity without mechanical shaft penetration. The dual-model architecture allows users to select between two thermally optimized heating plate technologies: the UC152 employs a high-purity glass-ceramic surface offering exceptional chemical resistance and optical clarity for visual monitoring of color-sensitive reactions; the US152 utilizes a robust ceramic-coated aluminum-silicon alloy plate with enhanced thermal conductivity and rapid heat-up performance. Both models integrate a microprocessor-controlled PID temperature regulation system, enabling stable setpoint maintenance within ±3 °C across the full 0–325 °C range (UC152 extends to 450 °C), making them suitable for applications ranging from gentle buffer equilibration to vigorous reflux conditions.

Key Features

• Two interchangeable heating plate options: chemically inert glass-ceramic (UC152) or high-conductivity ceramic-coated Al-Si alloy (US152)
• Dual-mode LED temperature display with intuitive scale-based indication for real-time thermal feedback
• Independent “HOT” warning indicator—flashes when surface temperature exceeds 50 °C, regardless of power state, enhancing lab safety compliance
• High-torque brushless motor delivering stable rotational speeds from 100 to 2000 rpm, even at maximum load (15 L in a 20 L borosilicate flask)
• Integrated support rod mounting holes (M6 thread) compatible with standard lab clamping systems
• Pre-installed PTFE-coated stir bars (2 × 25 mm) resistant to acid, base, and organic solvent exposure
• Compact footprint (172 × 248 × 120 mm) and lightweight design (2.9 kg) for benchtop flexibility and storage efficiency
• IP32-rated enclosure providing protection against vertically falling droplets and solid objects ≥2.5 mm

Sample Compatibility & Compliance

The UC152/US152 series is validated for use with common laboratory vessels including borosilicate glass beakers, Erlenmeyer flasks, round-bottom flasks, and stainless-steel containers up to 20 L capacity. The inert surface chemistry of both heating plates ensures compatibility with aggressive reagents such as concentrated HCl, HNO₃, NaOH, and acetone-based solvents. These instruments conform to IEC 61010-1:2010 for electrical safety in laboratory equipment and meet CE marking requirements under the EU Low Voltage Directive (2014/35/EU) and EMC Directive (2014/30/EU). While not inherently 21 CFR Part 11 compliant, the optional SCT1 digital temperature controller (sold separately) supports audit-trail-capable logging when integrated into GLP/GMP workflows requiring traceable thermal process records.

Software & Data Management

The UC152 and US152 operate as standalone analog-digital hybrid instruments with no embedded firmware or network connectivity. Temperature and speed settings are adjusted via tactile rotary dials with LED-assisted resolution (1 °C and 10 rpm increments respectively). For advanced data capture, the externally mounted SCT1 digital temperature controller provides RS232 output, enabling integration with third-party acquisition software (e.g., LabVIEW, MATLAB) or LIMS platforms. The SCT1 logs timestamped temperature readings at user-defined intervals (1–60 s), stores up to 10,000 data points internally, and supports CSV export via USB. All configurations maintain full traceability under ISO/IEC 17025-compliant calibration protocols when paired with NIST-traceable reference thermometers.

Applications

• Preparation and homogenization of culture media, buffers, and reagent solutions in microbiology and molecular biology labs
• Controlled heating and mixing during titration, dissolution testing, and standard solution preparation per USP & EP guidelines
• Accelerated reaction kinetics studies requiring precise thermal ramping and agitation stability
• Viscosity assessment of low-to-medium viscosity liquids where shear history must be minimized
• Sample conditioning prior to analysis by HPLC, GC, or spectrophotometry to ensure thermal equilibrium and compositional uniformity
• Teaching laboratories demonstrating thermodynamic principles, reaction rate dependencies, and safe hotplate operation practices

FAQ

Can the UC152/US152 be used with non-magnetic vessels such as plastic or aluminum containers?

No. Magnetic coupling requires ferromagnetic or paramagnetic transmission through the vessel base; only non-ferrous glass, ceramic, or thin-walled stainless-steel containers are compatible.
Is the “HOT” indicator active when the unit is unplugged but retains residual heat?

Yes. The thermal sensor operates independently of mains power and triggers the LED whenever the plate surface exceeds 50 °C.
What is the recommended calibration frequency for temperature accuracy?

Annual calibration against a NIST-traceable thermometer is advised for GLP environments; more frequent verification (e.g., quarterly) is recommended in high-throughput QC labs.
Do both models support external temperature probe input?

Only when used with the optional SCT1 controller, which accepts Pt100 or thermocouple inputs for sample-immersed feedback control.
Are replacement stir bars available in different sizes or coatings?

Yes. Stuart offers PTFE, PTFE-glass, and PTFE-encapsulated samarium-cobalt stir bars in lengths from 10 mm to 50 mm, all chemically rated for Class A laboratory use.