Carbolite Gero PTC 12/20 Thermocouple Calibration Furnace

Overview

The Carbolite Gero PTC 12/20 is a precision-engineered portable tube furnace designed specifically for thermocouple calibration and verification in laboratory, metrology, and industrial quality assurance environments. Operating on the principle of stable, uniform resistive heating within a metallurgically sealed working tube, the PTC 12/20 delivers traceable thermal stability across a calibrated range of 400 °C to 1200 °C — with a maximum operating temperature of 1200 °C. Its compact geometry and optimized thermal mass enable rapid ramp rates (≤20 minutes to full temperature) without compromising short-term stability (<±3 °C over 30-minute dwell) or axial/radial uniformity. Unlike general-purpose muffle furnaces, the PTC 12/20 integrates a dedicated ground-referenced metal working tube that eliminates stray potential and ensures electrical safety when calibrating mineral-insulated (MI) thermocouples — a critical requirement under IEC 61543 and ISO/IEC 17025-compliant calibration workflows.

Key Features

• High-stability thermal source with proven uniformity of ±3 °C across the 400–1200 °C calibration range
• Compact, lightweight design (8 kg net weight) enabling both benchtop lab use and field-deployable calibration tasks
• PID-based digital temperature controller with 1.0 °C display resolution and intuitive setpoint programming
• Optimized 20 mm internal diameter working tube engineered for superior radial temperature homogeneity compared to standard tube furnaces of equivalent size
• Electrically grounded stainless steel working tube — compatible with MI-type thermocouples and compliant with electrical safety requirements for Class I equipment (IEC 61010-1)
• Resistance wire heating system delivering consistent thermal output with low thermal inertia and high reproducibility
• Thermocouple insertion port accommodating probes up to 7.5 mm outer diameter, supporting common types including K, N, R, S, B, and T

Sample Compatibility & Compliance

The PTC 12/20 is validated for calibration of industrial and reference-grade thermocouples used in process control, aerospace testing, and materials research. It supports direct comparison between the unit-under-test (UUT) and a calibrated reference sensor inserted coaxially into the same working tube. The furnace meets essential metrological prerequisites for ISO/IEC 17025-accredited laboratories, including documented temperature uniformity profiles, thermal stability metrics, and traceable uncertainty budgets. Optional UKAS-accredited calibration certificates (issued under the former NAMAS framework) are available upon order, covering three key reference points: 700 °C, 900 °C, and 1100 °C. These certificates include measurement uncertainty statements aligned with EURAMET cg-18 guidelines and are recognized by national metrology institutes worldwide.

Software & Data Management

While the PTC 12/20 operates as a standalone analog/digital instrument, its temperature controller features RS232 communication capability for integration with external data acquisition systems. When paired with compliant software (e.g., LabVIEW, MATLAB, or proprietary calibration suites), users can log time-stamped temperature readings, generate automated calibration reports, and embed audit trails required for GLP and GMP environments. All calibration records generated using optional factory or UKAS-certified services comply with FDA 21 CFR Part 11 requirements for electronic records and signatures when implemented with appropriate validation protocols and access controls.

Applications

• Primary and secondary thermocouple calibration in metrology labs and accredited calibration service providers
• In-house verification of temperature sensors prior to deployment in high-temperature manufacturing processes (e.g., heat treatment, sintering, ceramic firing)
• Validation of thermocouple performance in accordance with ASTM E230, IEC 60584, and ISO 8573-1
• Field calibration support for maintenance teams servicing kilns, reactors, and turbine test rigs
• Educational demonstrations of thermoelectric principles, thermal equilibrium, and uncertainty propagation in temperature measurement

FAQ

What temperature range is validated for calibration accuracy?
The PTC 12/20 is characterized and certified for stable operation from 400 °C to 1200 °C, with optimal uniformity and stability achieved above 400 °C.
Can it be used to calibrate Type B thermocouples?
Yes — the furnace’s upper limit of 1200 °C accommodates the full useful range of Type B thermocouples (up to 1700 °C), though calibration is typically performed at defined reference points below 1200 °C where uncertainty is minimized.
Is the working tube replaceable or serviceable?
The grounded stainless steel working tube is a permanent, non-consumable component; however, Carbolite Gero provides technical documentation and authorized service support for thermal recalibration and controller diagnostics.
Does the unit meet electromagnetic compatibility (EMC) standards for laboratory use?
Yes — the PTC 12/20 complies with EN 61326-1 for laboratory equipment and carries CE marking for EMC and safety conformity within the European Economic Area.
How is traceability maintained during calibration?
Traceability is ensured via optional UKAS-accredited certificates linked to national standards (NPL, UK), or through factory calibration referenced to Carbolite Gero’s primary standard platinum resistance thermometer (PRT) chain, fully documented per ISO/IEC 17025 clause 6.6.