CZGY SHJ-2A Digital Constant-Temperature Magnetic Stirring Water Bath

Overview

The CZGY SHJ-2A Digital Constant-Temperature Magnetic Stirring Water Bath is an engineered dual-chamber laboratory thermal platform designed for simultaneous, independent temperature control and magnetic stirring of up to two samples. It operates on the principle of resistive heating combined with PID-based digital temperature regulation and permanent-magnet-driven stirring—ensuring stable thermal environments and uniform mixing without mechanical shaft penetration. Each chamber features a sealed stainless steel tank (φ20 cm × 10 cm depth), enabling precise immersion-based heating of reaction vessels, sample tubes, or culture flasks. The unit is intended for routine applications in life sciences, analytical chemistry, pharmaceutical QC, and materials preparation where reproducible thermal conditioning and gentle agitation are required—such as enzyme incubation, solubility testing, dissolution studies, and buffer equilibration.

Key Features

• Dual independent chambers with separate digital PID controllers, allowing concurrent operation at different setpoints within the ambient+5°C to 100°C range
• High-resolution digital display showing real-time temperature and stirring speed for each station
• Magnetic stirring mechanism with adjustable speed from 0 to 2400 rpm per chamber—compatible with standard PTFE-coated stir bars (up to 60 mm length)
• Stainless steel inner tanks and solid stainless steel working surface—resistant to corrosion, thermal shock, and repeated cleaning with aqueous or mild solvent solutions
• Epoxy-coated cold-rolled steel housing for mechanical durability and long-term resistance to ambient lab moisture and chemical splashes
• Integrated timer function (0–999 minutes) with auto-shutdown capability for unattended operation
• Drain port located at the base of each chamber for rapid, spill-free fluid removal
• Modular accessory system including two stainless steel support rods, two condenser clamps, and two 5-loop circular aluminum lids for reflux or vapor containment

Sample Compatibility & Compliance

The SHJ-2A accommodates standard laboratory glassware—including 50 mL to 1000 mL beakers, Erlenmeyer flasks, and cylindrical digestion tubes—within its dual bath chambers. Its construction complies with general safety requirements for Class I electrical equipment per IEC 61010-1. While not certified to UL/CSA or CE for medical device use, it meets typical institutional procurement specifications for non-GMP teaching and research laboratories. The stainless steel wetted parts satisfy ASTM A240 Type 304 material equivalency for aqueous compatibility. For GLP-compliant workflows, users may configure manual log entries or integrate external data capture via RS232 (optional interface module available upon request). The unit does not include 21 CFR Part 11-compliant audit trail functionality out-of-the-box but supports traceable operation when paired with validated third-party data acquisition software.

Software & Data Management

The SHJ-2A operates via embedded microcontroller firmware with no onboard software stack. All parameter inputs—temperature setpoint, stirring speed, and timer duration—are entered directly through tactile membrane keys and confirmed via LED display feedback. No proprietary drivers, USB connectivity, or cloud synchronization are implemented. Data recording must be performed manually or using external thermocouple-based dataloggers (e.g., Omega OM-DAQPRO or Testo 176 T4). Optional RS232 output (available as factory-configured add-on) enables serial transmission of current temperature and status codes to host PCs running custom LabVIEW, Python, or MATLAB scripts for batch logging and alarm triggering.

Applications

• Controlled-temperature enzymatic reactions requiring continuous mixing (e.g., restriction digests, ligations, protein refolding)
• Dissolution testing of solid dosage forms under USP conditions (when used with calibrated vessels and validated protocols)
• Pre-equilibration of mobile phases and standards prior to HPLC or GC analysis
• Cell culture media warming and pH buffer stabilization before inoculation
• Synthesis of temperature-sensitive nanoparticles (e.g., liposomes, polymeric micelles) with shear-controlled nucleation
• Calibration of liquid-in-glass thermometers and RTDs against NIST-traceable references
• Accelerated stability studies for excipients and formulations per ICH Q1A(R2) guidelines (as auxiliary thermal platform)

FAQ

Does the SHJ-2A support external temperature probe input for chamber calibration verification?
No—the unit relies solely on internal Pt100 sensors embedded in each bath chamber. Independent verification requires insertion of a calibrated reference thermometer into the fluid medium.
Can the stirring function operate without heating enabled?
Yes. Temperature and stirring controls are fully decoupled; either function may be used independently.
Is the unit suitable for use with organic solvents such as acetone or ethanol?
Only with caution: while the stainless steel tank is chemically resistant, prolonged exposure to low-surface-tension solvents may compromise seal integrity and promote vapor infiltration into the electronics compartment. Not recommended for extended reflux with volatile organics.
What is the maximum recommended fill level for each chamber?
To ensure optimal thermal uniformity and prevent overflow during stirring, maintain liquid levels between 1.5 L and 2.8 L per 3 L chamber.
Are replacement stir bars and lids available as spare parts?
Yes—CZGY supplies OEM-compatible PTFE-coated stir bars (40 mm and 60 mm lengths) and additional 5-loop aluminum lids under part numbers SB-40, SB-60, and CL-5L, respectively.