CZGY 79-1 Magnetic Hotplate Stirrer

Overview

The CZGY 79-1 Magnetic Hotplate Stirrer is a compact, benchtop laboratory instrument engineered for simultaneous magnetic stirring and conductive heating of liquid samples in glass vessels. It operates on the principle of rotating magnetic field coupling: an internal permanent magnet rotor—driven by a low-noise, brushless synchronous motor—generates a time-varying magnetic field beneath a chemically resistant ceramic-coated steel plate. This field induces rotation in a PTFE- or glass-coated magnetic stir bar placed inside the sample container. Heat is delivered via embedded resistive heating elements under the plate surface, with temperature regulated through a bimetallic thermostat-based analog control system. Designed for routine use in teaching laboratories, QC/QA environments, and preparatory workflows, the 79-1 delivers stable thermal and rotational performance across aqueous, organic, and mildly corrosive media—provided compatibility with vessel material (e.g., borosilicate glass) and stir bar coating is verified.

Key Features

• Integrated hotplate and stirrer in a single, space-efficient unit with footprint under 180 × 150 mm
• Smooth, stepless speed control from 0 to 1600 rpm via front-panel rotary knob—optimized for gentle homogenization or vigorous mixing of low-to-medium viscosity solutions
• Analog temperature regulation with fixed-range setting (ambient to 100 °C); no digital display, but calibrated for ±5 °C accuracy under steady-state conditions
• 120 mm diameter heating/stirring surface constructed from chromium-plated steel—resistant to minor spills and mechanical abrasion during routine handling
• 25 W motor power ensures consistent torque delivery up to 1 L volume with standard stir bars (e.g., 30 mm × 8 mm), while 150 W heating capacity enables rapid warm-up of water-equivalent loads
• No external controller required; all operation performed locally via two independent toggle switches (stirring ON/OFF and heating ON/OFF) and dual analog dials (speed + temperature)
• Grounded chassis design compliant with IEC 61010-1 safety requirements for laboratory electrical equipment

Sample Compatibility & Compliance

The 79-1 supports standard laboratory glassware including beakers (50–1000 mL), Erlenmeyer flasks, and round-bottom flasks placed directly on the plate surface. Compatible stir bars include PTFE-coated, glass-coated, and Alnico-core magnets rated for temperatures up to 100 °C. The unit is not suitable for sealed vessels, volatile solvents without condensation control, or highly viscous non-Newtonian fluids exceeding 5000 mPa·s at operating temperature. While not certified to ISO/IEC 17025 or GLP-specific validation protocols, its construction adheres to general-purpose lab equipment safety standards (IEC 61010-1), and its analog control architecture meets basic traceability requirements for non-regulated educational and industrial R&D applications. No software-based audit trail or electronic record functionality is included.

Software & Data Management

The CZGY 79-1 operates exclusively via analog controls and does not incorporate microprocessor-based logic, digital interface, or data logging capability. All operational parameters—including speed and setpoint temperature—are manually selected and maintained without feedback compensation or real-time monitoring output. Consequently, no drivers, firmware updates, or PC connectivity options are available. Users must rely on external thermometers (e.g., calibrated RTD or thermocouple probes) and tachometers for independent verification of thermal and rotational performance. This architecture ensures electromagnetic compatibility in RF-sensitive environments and eliminates cybersecurity or validation overhead associated with connected instrumentation.

Applications

• Precipitation reactions and reagent dissolution in analytical chemistry labs
• pH adjustment and buffer preparation in molecular biology and microbiology workflows
• Heating-assisted extraction of plant metabolites or soil analytes prior to HPLC or GC analysis
• Standard solution preparation for calibration curves in UV-Vis spectrophotometry
• Pre-incubation of culture media in teaching laboratories (e.g., nutrient broth warming prior to sterilization)
• Supporting role in gravimetric analysis—maintaining homogeneous suspension during filtration or titration steps
• Low-risk solvent warming in synthetic chemistry pre-reaction setup (excluding ether, acetone, or low-boiling point organics without reflux control)

FAQ

Is the 79-1 compatible with stainless steel or aluminum containers?
No. Only non-magnetic, thermally conductive materials such as borosilicate glass or ceramic are suitable. Metal containers disrupt the magnetic field and may overheat unevenly.
Can the unit maintain precise temperature setpoints for extended periods?
It provides approximate thermal control within ±5 °C under static load conditions; it lacks PID regulation or active cooling, so drift may occur during prolonged operation above 80 °C.
What maintenance is required to ensure long-term reliability?
Wipe the plate surface after each use with a lint-free cloth dampened with deionized water; avoid abrasive cleaners. Inspect stir bars for coating integrity before reuse. Store in a dry, vibration-free location.
Does the device support continuous 24/7 operation?
Intermittent use is recommended. Continuous heating beyond 4 hours increases thermal stress on internal components and may reduce heater element lifespan.
Are replacement parts such as stir bars or power cords available through CZGY?
Yes—standard PTFE-coated stir bars (20 mm and 30 mm), replacement power cables (IEC C13 type), and spare fuses (250 V, 1 A slow-blow) are stocked and orderable directly from the manufacturer.