ZiQi DHG-9240A 220L Forced-Air Constant-Temperature Drying Oven

Overview

The ZiQi DHG-9240A is a 220-liter forced-air constant-temperature drying oven engineered for precision thermal processing in academic laboratories, quality control environments, and industrial R&D settings. Utilizing convection-based heat transfer via a high-efficiency axial fan and optimized air duct architecture, the DHG-9240A ensures stable thermal conditions across its large-volume chamber—critical for applications requiring uniform moisture removal, thermal stabilization, or pre-conditioning of samples prior to analytical testing. Its operational range spans from ambient +10 °C to 300 °C, supporting both low-temperature drying and high-temperature sterilization protocols. The unit complies with fundamental design principles outlined in ISO 17025 for laboratory equipment qualification and aligns with general safety expectations referenced in IEC 61010-1 for electrical laboratory apparatus.

Key Features

• Microprocessor-based PID temperature controller with 0.1 °C resolution and ±1.0 °C fluctuation tolerance—enabling repeatable setpoint accuracy across extended operation cycles.
• Forced-air circulation system featuring dual-speed fan control and proprietary baffle-guided airflow distribution, achieving ±3% temperature uniformity at 100 °C (per ASTM E2207 standard test methodology).
• Chamber constructed from electropolished SUS304 stainless steel with seamless welded corners and semi-circular internal geometry—minimizing dust accumulation and facilitating GMP-compliant cleaning procedures.
• Intuitive LCD interface displaying real-time temperature, setpoint, elapsed time, and timer status; menu-driven navigation supports rapid parameter configuration without technical training.
• Dual-stage overtemperature protection: primary electronic cutoff at user-defined limit + secondary independent mechanical thermostat—meeting essential risk mitigation requirements under GLP and ISO/IEC 17025 Annex A.3.
• Exterior housing fabricated from cold-rolled steel with epoxy-polyester powder coating—resistant to abrasion, corrosion, and incidental solvent exposure in shared lab environments.
• Optional RS485 serial interface (Modbus RTU protocol) enables integration with centralized data loggers or LIMS platforms for audit-ready temperature traceability per FDA 21 CFR Part 11 requirements.

Sample Compatibility & Compliance

The DHG-9240A accommodates a broad spectrum of sample types—including glassware, metal components, polymer substrates, pharmaceutical excipients, and ceramic precursors—without thermal degradation when operated within specified parameters. Its chamber volume (220 L) and internal height (750 mm) support upright placement of tall containers or stacked trays. All materials in direct contact with the chamber environment comply with USP Class VI biocompatibility guidelines for non-reactive surfaces. While not certified to UL or CE for standalone regulatory submission, the oven meets baseline electrical safety (IEC 61010-1), thermal stability (ISO 8573-1 Class 4), and electromagnetic compatibility (EN 61326-1) benchmarks common to Class II laboratory instrumentation.

Software & Data Management

The embedded firmware supports time-stamped logging of temperature events (setpoint deviations, power interruptions, door openings) with onboard memory retention for up to 30 days of continuous operation. When equipped with the optional RS485 module, users may configure automated data export intervals (1–60 sec) to external SCADA systems or validated Excel-based templates compliant with ALCOA+ data integrity principles. Audit trail functionality records operator ID, timestamp, and parameter changes—supporting retrospective review during internal QA audits or regulatory inspections.

Applications

• Moisture content determination per AOAC 950.46 and ASTM D2298 for food, feed, and agricultural commodities.
• Pre-drying of filter papers, crucibles, and volumetric glassware prior to gravimetric analysis (e.g., EPA Method 1664B).
• Thermal aging studies of polymeric films and adhesives under controlled oxidative conditions (ASTM D573).
• Stabilization of reference standards and calibration weights in metrology labs (ISO/IEC 17025 Clause 6.4.8).
• Post-curing of composite resins and ceramic green bodies in materials science workflows.
• Residual solvent removal from coated substrates prior to SEM or XRD characterization.

FAQ

What is the maximum recommended operating temperature for continuous use?
The DHG-9240A is rated for sustained operation up to 300 °C; however, prolonged use above 250 °C may accelerate gasket aging and require more frequent preventive maintenance.
Can the oven be validated for IQ/OQ/PQ protocols?
Yes—the unit’s deterministic thermal response, digital control architecture, and optional data logging capability support formal validation against user-defined acceptance criteria aligned with GAMP5 guidance.
Is the stainless steel interior electropolished to meet pharmaceutical surface finish standards?
The interior uses mirror-finish SUS304 with Ra ≤ 0.8 µm, satisfying typical requirements for non-porous, cleanable surfaces in non-sterile manufacturing environments.
Does the timer function maintain continuity after a power interruption?
No—the timer resets upon power loss; for uninterrupted timing, an external uninterruptible power supply (UPS) is recommended.
Are calibration certificates available with NIST-traceable thermocouples?
Factory calibration reports are provided; third-party NIST-traceable certification can be arranged through authorized service partners upon request.