Nabertherm L 5/13 Laboratory Muffle Furnace

Overview

The Nabertherm L 5/13 is a precision-engineered laboratory muffle furnace designed for controlled high-temperature thermal processing in research, quality control, and materials development environments. Operating on the principle of radiant heat transfer via horizontally mounted resistance heating elements embedded in ceramic support tubes, it achieves rapid and uniform thermal distribution within the insulated chamber. Its robust construction—featuring dual-layer stainless steel housing and multi-layer lightweight refractory brick insulation—enables stable operation at its maximum rated temperature of 1300 °C while maintaining low external surface temperatures (<60 °C under continuous operation), ensuring operator safety and energy efficiency. The furnace complies with EN 60519-2 for industrial electroheating equipment safety, incorporating dual independent temperature control circuits and a certified Class 2 thermal cut-off limiter to prevent overheating of both chamber and sample.

Key Features

• High-precision temperature control with ±1 °C stability across the full operating range (room temperature to 1300 °C)
• Dual-sided heating configuration using NiCr resistance wire elements mounted on ceramic support tubes for enhanced thermal homogeneity and extended service life
• Optimized insulation system composed of low-conductivity lightweight refractory bricks, minimizing thermal lag and improving energy retention
• Modular door options: front-hinged (L series) for easy horizontal loading or top-lifting (LT series) for vertical access—both equipped with adjustable air inlet and rear-mounted exhaust port
• Low-noise operation enabled by solid-state relay (SSR) switching and optimized airflow design
• Integrated overtemperature protection per EN 60519-2, including redundant limit sensors and programmable thermal cut-off setpoints
• Standard gas purge interface compatible with inert (N₂, Ar) or reactive atmospheres (e.g., H₂/N₂ mixtures), supporting ASTM E1111 and ISO 8501-1 compliant thermal treatments

Sample Compatibility & Compliance

The L 5/13 accommodates a broad range of sample forms—including crucibles (alumina, quartz, silicon carbide), ceramic tiles, metal powders, catalyst substrates, and ashing vessels—within its 4.4 L internal chamber (130 × 170 × 200 mm). Its uniform temperature zone (±5 °C over 80% of chamber volume at 1300 °C) meets requirements for ASTM E1111 (ash content determination), ISO 562 (volatile matter analysis), and USP heavy metals testing. The furnace supports GLP/GMP-aligned workflows through optional NTLog data logging (USB-based), traceable to NIST-traceable calibration standards. All electrical components conform to CE marking directives (2014/30/EU EMC, 2014/35/EU LVD), and thermal safety architecture satisfies IEC 61000-6-2 immunity and IEC 61000-6-4 emission standards.

Software & Data Management

The standard Nabertherm controller includes NTLog basic functionality, enabling time-stamped recording of temperature profiles, setpoint changes, and alarm events directly to USB flash media—supporting audit-ready documentation for FDA 21 CFR Part 11–compliant environments when paired with user-defined electronic signatures. Optional VCD (Virtual Control Device) software provides remote monitoring, multi-furnace synchronization, real-time graphing, and export to CSV or XML formats for integration into LIMS or MES platforms. Process recipes can be saved, version-controlled, and password-protected; all data logs include metadata such as operator ID, furnace serial number, and environmental timestamp.

Applications

• Thermal gravimetric analysis (TGA) sample pre-treatment and residue quantification
• Ash content determination in food, pharmaceuticals, and environmental samples per AOAC 942.05 and EPA Method 200.7
• Ceramic sintering, glass annealing, and metallurgical heat treatment (e.g., stress relieving, normalizing)
• Calibration of thermocouples and RTDs using fixed-point reference materials (e.g., Al, Zn, Ag melting points)
• Preparation of catalyst supports and battery electrode materials requiring controlled oxidative or inert-atmosphere calcination
• Residue-on-ignition testing in cement, fly ash, and geological samples per ASTM C114 and ISO 29581-1

FAQ

What is the recommended maintenance interval for the heating elements and insulation?
Heating elements require inspection every 200 operational hours; refractory lining integrity should be verified annually or after exposure to thermal shock or corrosive atmospheres.
Can the L 5/13 be operated under vacuum or reduced pressure?
No—this model is not rated for vacuum use. For controlled atmosphere applications, only positive-pressure inert or reactive gas purging is supported via the standard 6-mm BSP gas inlet.
Is the furnace compatible with third-party SCADA systems?
Yes—via optional RS485 Modbus RTU interface (Nabertherm Art. No. 1001252), enabling integration with Siemens Desigo, Schneider EcoStruxure, or Allen-Bradley ControlLogix platforms.
Does the unit include factory calibration documentation?
Each furnace ships with a DIN EN ISO/IEC 17025–accredited calibration certificate covering TUS (Temperature Uniformity Survey) at 1300 °C, traceable to PTB (Physikalisch-Technische Bundesanstalt).
What safety certifications does the L 5/13 hold?
CE-marked per Machinery Directive 2006/42/EC, Low Voltage Directive 2014/35/EU, and EMC Directive 2014/30/EU; additionally tested to UL 61010-1:2012 and CSA C22.2 No. 61010-1-12 for North American markets.