JingHong DK-S24 Digital Constant-Temperature Water Bath

Overview

The JingHong DK-S24 Digital Constant-Temperature Water Bath is an entry-level yet robust thermal platform engineered for precise, stable temperature maintenance in routine laboratory workflows. Operating on the principle of convective heat transfer through a water medium, it delivers uniform thermal energy distribution across its four independent wells—enabling simultaneous processing of multiple samples under identical thermal conditions. Unlike circulating baths or oil-based systems, this unit relies on passive convection within a sealed stainless steel reservoir, optimized for applications requiring modest temperature accuracy (±0.3 °C at 37 °C) and long-term stability (≤0.2 °C drift over 8 hours). Its design targets general-purpose use in teaching labs, QC environments, enzymatic assays, sample thawing, reagent warming, and incubation support where strict regulatory compliance (e.g., ISO 17025 or GLP) is not mandated but reproducibility remains essential.

Key Features

• Seamless one-piece stainless steel inner chamber—formed via cold stamping without welds—to prevent corrosion, leakage, or crevice accumulation; enhances cleaning efficiency and extends service life.
• Microprocessor-controlled PID temperature regulation system with dual digital LED display: left digit shows setpoint temperature, right digit shows real-time bath temperature—enabling immediate visual verification of control status.
• Auto-tuning PID algorithm adapts dynamically to load changes (e.g., insertion of cold vessels), minimizing overshoot and reducing stabilization time by up to 40% compared to basic on/off thermostats.
• Dual-row, four-well configuration (2 × 2 layout) accommodates standard test tubes (up to Ø25 mm), flasks, and beakers; well depth supports immersion of samples up to 150 mm.
• Over-temperature safety cut-off (activated at 105 °C) and dry-run protection circuitry prevent heater damage during accidental operation without water.
• Front-panel membrane keypad with tactile feedback ensures reliable input even with gloved hands; non-volatile memory retains last-used setpoint after power interruption.

Sample Compatibility & Compliance

The DK-S24 accepts glass, polypropylene, and stainless steel containers compatible with aqueous media and temperatures ≤99 °C. It is unsuitable for organic solvents (e.g., acetone, ethanol), corrosive solutions (e.g., strong acids/bases), or applications demanding inert atmospheres. While not certified to IEC 61010-1 Ed. 3 or UL 61010B, the unit conforms to Chinese national standards GB/T 28001 (Occupational Health and Safety) and aligns with infrastructure requirements for ISO/IEC 17025-accredited laboratories performing non-critical thermal conditioning steps. It does not meet FDA 21 CFR Part 11 requirements for electronic records or audit trails; therefore, manual logbook documentation is recommended for regulated workflows.

Software & Data Management

This is a standalone analog-digital hybrid instrument with no embedded data logging, USB connectivity, or PC interface. All operational parameters—including setpoint, actual temperature, and elapsed run time—are monitored locally via the front-panel display. Users must manually record temperature readings at defined intervals using external thermometers (e.g., calibrated Pt100 probe) if traceable documentation is required. No firmware updates or remote diagnostics are supported. For laboratories requiring automated data capture, integration with third-party DAQ systems (e.g., National Instruments USB-TC01) is possible via optional analog output (0–5 V DC proportional to bath temperature), though such modification voids factory warranty and requires user calibration.

Applications

• Biological sample preparation: enzyme activation, DNA denaturation/annealing simulations, serum inactivation, and cell culture media pre-warming.
• Chemical dissolution testing: solubility studies of APIs, polymer swelling kinetics, and standardization of buffer equilibration protocols.
• Quality control procedures: viscosity reference checks (when paired with rotational viscometers), stability testing of emulsions, and thermal validation of packaging adhesives.
• Educational demonstrations: Arrhenius equation modeling, heat capacity estimation, and phase transition observation in undergraduate physical chemistry labs.
• Pharmaceutical auxiliary tasks: tablet coating solution tempering, gelatin melt-point verification, and excipient hydration control prior to granulation.

FAQ

What is the maximum recommended operating temperature for continuous use?
The DK-S24 is rated for sustained operation at 99 °C. Prolonged use above 95 °C may accelerate evaporation and require more frequent water top-ups.
Can this water bath accommodate round-bottom flasks?
Yes—each well has a diameter of 85 mm and depth of 150 mm, supporting common 50–250 mL round-bottom flasks when used with appropriate support rings.
Is calibration certificate included with shipment?
No. A factory calibration report is available upon request at additional cost; users are advised to perform initial verification using a NIST-traceable thermometer before first use.
Does the unit have a drain valve?
No. Emptying requires manual tilting or siphoning; users should allow full cooldown before handling.
What maintenance is required to ensure long-term accuracy?
Monthly descaling with 10% citric acid solution is recommended for hard-water regions; annual inspection of heater element continuity and thermostat response time is advised.