Memmert UNB500 Natural Convection Drying Oven

Overview

The Memmert UNB500 Natural Convection Drying Oven is a precision-engineered laboratory oven designed for reliable, uniform thermal processing in applications ranging from routine sample drying and moisture determination to material aging, preheating, and stabilization protocols. Built on Memmert’s decades-long heritage in thermal instrumentation, the UNB500 operates on natural convection—relying on buoyancy-driven air movement without forced airflow—to deliver gentle, low-turbulence heating ideal for heat-sensitive or particulate-laden samples. Its all-stainless-steel construction (1.4301 / ASTM 304), fully welded and spot-weld-free chassis, and DIN-compliant thermal performance ensure long-term dimensional stability, corrosion resistance, and compliance with stringent laboratory quality standards—including GLP, ISO/IEC 17025, and internal audit requirements for traceable temperature control.

Key Features

• Chamber constructed entirely from deep-drawn, 100% recyclable stainless steel (1.4301 / ASTM 304), including interior walls, door, and sliding shelves—eliminating galvanic corrosion and facilitating cleaning validation.
• Natural convection design ensures laminar, vibration-free thermal environment—critical for powders, filter papers, biological substrates, and coated wafers where forced airflow may cause displacement or surface disturbance.
• Temperature range: +20 °C to +220 °C (standard configuration); extended operation up to +300 °C available upon specification.
• Electronic PID microprocessor controller with integrated self-diagnostic routines, fuzzy logic adaptation, and dual Pt100 Class A sensors (4-wire) for redundancy and fault-tolerant operation.
• Independent mechanical temperature limiter (TB Class 1) set ~10 °C above maximum operating temperature—providing fail-safe thermal cutoff independent of electronic control circuitry.
• DIN 12880–compliant chamber temperature uniformity: ≤ ±2.7 °C at 150 °C (measured at 9 points across working volume), verified via factory-issued calibration certificate (center-point reference at 160 °C).
• High-resolution 8-digit alphanumeric display with multilingual UI (D/UK/E/F/I), real-time visualization of setpoint, actual temperature, elapsed time, remaining runtime, and active alarm status.
• Integrated digital timer with programmable hold, ramp, and soak functions—supporting up to 4 temperature ramps (each configurable from 1 minute to 999 hours) and unlimited cycle repetition (1–99× or infinite).

Sample Compatibility & Compliance

The UNB500 accommodates a broad spectrum of sample formats—including Petri dishes, crucibles, glassware, metal trays, and polymer films—within its 108 L usable chamber volume (560 × 480 × 400 mm W×H×D). Five adjustable stainless-steel sliding shelves (max. load 30 kg per shelf; total chamber load capacity 60 kg) support flexible loading configurations. The oven meets key international regulatory expectations: temperature accuracy (±0.5 °C setpoint deviation), display resolution (0.1 °C below 100 °C; 0.5 °C above), and thermal stability (≤ ±0.5 °C drift over time at 150 °C). It supports IQ/OQ documentation packages and is compatible with 21 CFR Part 11–compliant data archiving when used with Celsius 2007 software and optional USB-to-parallel printer adapters.

Software & Data Management

The included Celsius 2007 software (Windows NT4 through Windows 10 compatible) enables full remote programming, real-time monitoring, and audit-trail–capable data logging. Users can define unlimited temperature profiles—including ramp rates, dwell times, fan modulation (where applicable), and ventilation control—directly from PC. Internal ring-buffer memory (1024 kB) stores timestamped records of setpoints, actual temperatures, alarms, and system events at user-defined intervals (down to 1-minute resolution), retaining approximately six months of continuous data. Optional STERI chip cards allow validated sterilization cycles (e.g., 4 h @ 160 °C), while XL memory cards (32 kB) store up to 40 multi-segment programs for standalone execution—ideal for unattended overnight runs in regulated environments.

Applications

• Moisture content analysis per ASTM D2231, ISO 787-2, and USP <731>
• Thermal aging of polymers, adhesives, and composites per ASTM D3045 and IEC 60216
• Pre-drying of volumetric glassware and filtration apparatus prior to gravimetric analysis
• Stabilization of reference standards and calibration materials under controlled thermal history
• Low-stress curing of thin-film coatings and printed electronics substrates
• Residue evaporation in environmental and pharmaceutical residue testing workflows

FAQ

What is the difference between natural convection and forced convection ovens?
Natural convection relies on thermal buoyancy to circulate air—no fans or blowers are used—resulting in minimal air movement and reduced risk of sample disturbance. Forced convection employs motor-driven airflow for faster heat transfer but may compromise delicate or lightweight samples.
Does the UNB500 support GLP-compliant data recording?
Yes—when paired with Celsius 2007 software and a PCL3-compatible printer, it provides time-stamped, user-identifiable, and tamper-evident printouts meeting GLP documentation requirements.
Can the temperature uniformity be verified independently?
Yes—the oven ships with a single-point calibration certificate (center location at 160 °C) traceable to national standards; users may perform additional multi-point mapping using external Pt100 probes per ISO/IEC 17025 guidelines.
Is the UNB500 suitable for use in cleanroom environments?
Its stainless-steel construction, absence of paint or epoxy coatings, and zero outgassing design make it compatible with ISO Class 5–8 cleanrooms—provided ambient air intake is filtered and humidity-controlled.
What safety certifications does the UNB500 carry?
It complies with EN 61010-1 (Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use) and bears CE marking; optional ATEX certification is available for hazardous area deployment.