BOXUN DK-8D Triple-Independent-Zone Water Bath

Overview

The BOXUN DK-8D Triple-Independent-Zone Water Bath is a precision temperature-controlled laboratory instrument engineered for applications requiring simultaneous yet distinct thermal environments across three separate chambers. Unlike conventional single-zone water baths, the DK-8D employs a tri-chamber architecture with fully independent PID temperature regulation per well—enabling concurrent experiments at different setpoints without cross-contamination or thermal crosstalk. Each chamber operates on the principle of liquid-phase convective heat transfer, utilizing a stainless steel immersion bath medium (typically deionized water or low-viscosity silicone oil) heated via submerged resistive elements. The system’s core thermal performance—±0.1°C accuracy, ±0.3°C fluctuation, and ±0.5°C uniformity at 37°C—is validated under steady-state conditions per ISO 17025-aligned internal calibration protocols. Designed for routine use in clinical diagnostics labs, academic life science departments, and industrial QC settings, the DK-8D supports critical workflows including enzyme reaction incubation, DNA denaturation/annealing in PCR prep, cell culture reagent equilibration, and stability testing of thermolabile reagents.

Key Features

• Three physically isolated stainless steel wells (Ø165 × 120 mm each), enabling parallel processing of dissimilar samples under individually defined thermal profiles
• Dedicated high-resolution Pt100 platinum resistance thermometer per zone, coupled with a real-time CPU-driven PID control loop for dynamic response to load-induced thermal inertia
• Programmable timer with dual-mode functionality: delay start (up to 99 hours), auto shut-off, and fixed-setpoint scheduling for unattended overnight or multi-shift operation
• Comprehensive safety architecture including hardware-limited over-temperature cutoff, sensor open-circuit detection, deviation-based alarm thresholds, and audible/visual fault indication
• Intuitive digital interface with backlight LCD, user-accessible display calibration, non-volatile parameter memory, and automatic power-on recovery after interruption
• Robust mechanical construction: electropolished 304 stainless steel tank and lid, reinforced base chassis, and IP20-rated electrical enclosure compliant with IEC 61010-1 for laboratory equipment safety

Sample Compatibility & Compliance

The DK-8D accommodates standard laboratory glassware—including 15 mL and 50 mL conical tubes, universal test tubes (10–25 mm diameter), microcentrifuge tube racks, and small-volume beakers—without interference between adjacent wells. Its open-bath design permits direct insertion of sample containers while maintaining full visibility and accessibility. All wetted surfaces are passivated stainless steel, ensuring chemical compatibility with aqueous buffers, saline solutions, ethanol/water mixtures, and common diagnostic reagents. The unit conforms to key regulatory expectations for lab instrumentation: it supports GLP-compliant documentation through manual log entry of setpoints, actual temperatures, and timer events; its stable thermal output meets ASTM E104-22 requirements for humidity-controlled stability chambers when operated in ambient-humidity-limited environments; and its electrical safety certification aligns with GB 4793.1 (China) and IEC 61010-1 (international) standards for measurement, control, and laboratory equipment.

Software & Data Management

The DK-8D operates as a standalone analog-digital hybrid instrument with no embedded operating system or network interface. Temperature data is not automatically logged or exportable; however, the controller retains last-used parameters (setpoint, timer, alarm limits) across power cycles via EEPROM storage. For audit-trail compliance in regulated environments (e.g., ISO 13485 medical device manufacturing or CLIA-certified clinical labs), users may integrate external USB or RS-232 data loggers compatible with Pt100 output signals (available via optional analog output port on select firmware versions). The device supports manual verification per USP Analytical Instrument Qualification guidelines—specifically Installation Qualification (IQ) via physical inspection and Operational Qualification (OQ) through documented temperature mapping at multiple points within each well at 37°C and 65°C.

Applications

• Molecular biology: Pre-heating restriction enzymes, cooling post-digestion reactions, and maintaining constant temperature during ligation or transformation protocols
• Clinical pathology: Warming serum specimens prior to immunoassay analysis, equilibrating calibrators and controls, and thawing cryopreserved cell lines
• Pharmaceutical QA: Dissolution medium conditioning per USP , excipient solubility studies, and accelerated stability trials under controlled thermal stress
• Industrial R&D: Curing adhesives, annealing polymer films, and evaluating thermal degradation kinetics of composite materials
• Education: Demonstrating Arrhenius kinetics, enzyme activity vs. temperature profiles, and heat capacity measurements in undergraduate physical chemistry labs

FAQ

Does the DK-8D support remote monitoring or Ethernet connectivity?
No. The DK-8D is a locally operated instrument without built-in communication interfaces. Integration with building management systems or LIMS requires third-party analog-to-digital signal converters.
Can the unit operate continuously for 72+ hours?
Yes. With proper water level maintenance and ambient room temperature ≤30°C, the DK-8D is rated for uninterrupted operation up to 99 hours using its programmable timer function.
Is calibration certificate included with shipment?
A factory-as-tested calibration report (covering setpoint accuracy and uniformity at 37°C and 65°C) is provided. Full ISO/IEC 17025-accredited calibration must be arranged separately through authorized metrology service providers.
What maintenance is required to ensure long-term thermal stability?
Bi-weekly descaling with 5% citric acid solution (if using tap water), quarterly inspection of heater element continuity, and annual verification of Pt100 sensor drift against a NIST-traceable reference thermometer.
Are replacement parts such as lids or sensors available?
Yes. BOXUN supplies OEM-certified spare parts—including stainless steel lids, Pt100 probes, heating elements, and control boards—with documented traceability and compatibility validation for DK-8D units manufactured from 2018 onward.