Isotech Pegasus‑T — High‑Temperature Dry Block Calibrator for Short Sensors

The Isotech Pegasus‑T is a specialized high‑temperature dry block calibrator designed to solve a long‑standing challenge in temperature metrology: the accurate calibration of very short sensors. While conventional furnaces and even the Pegasus 4853 require substantial immersion depth, the Pegasus‑T introduces a unique dynamic heating zone specifically engineered for sensors with immersion lengths of 25 mm, 35 mm or 50 mm. It is ideal for industries such as automotive, materials processing, power generation and glass manufacturing, where compact sensors are widely used.

Why short sensors are difficult to calibrate

Accurate calibration requires that a sensor be immersed deeply enough to reach thermal equilibrium with the calibration block or furnace. Short sensors cannot reach this equilibrium, resulting in significant temperature gradients and measurement errors. The Pegasus 4853 offers 130 mm immersion, but sensors of 25–50 mm cannot be calibrated reliably in conventional systems. The Pegasus‑T was developed specifically to address this challenge.

Dynamic Heating Zone — optimized for short immersion probes

At the core of the Pegasus‑T is its dynamic heating zone, featuring three independent control loops. The user selects the control sensor corresponding to the immersion depth of the sensor under test:

• > Zone 1 — 25 mm
• > Zone 2 — 35 mm
• > Zone 3 — 50 mm

This creates a precisely controlled temperature environment exactly at the depth where the sensor is located, dramatically reducing temperature gradients and improving measurement accuracy.

External control sensor for maximum flexibility

In addition to the internal control sensors, the Pegasus‑T can be controlled using an external Type R thermocouple placed directly alongside the test sensor. This allows the block temperature to follow the actual temperature experienced by the sensor. An independent reference channel is included for external control or for use with a reference probe.

Accuracy and practical considerations

Short immersion probes inherently introduce larger uncertainties, but testing shows that the Pegasus‑T provides significantly better performance than alternative methods. Using a reference sensor of the same type as the units under test can further reduce uncertainty. The Pegasus‑T has already been adopted by several customers in Europe and Asia and is now available globally.

Custom calibration blocks

Because short sensors vary widely in geometry, the Pegasus‑T is supplied without an insert. Isotech can:

• > Design and manufacture custom inserts,
• > Supply blank inserts for local machining,
• > Or provide a pre‑drilled insert with 6 × 5 mm pockets, 100 mm deep.

This ensures perfect compatibility with any sensor design.

Advanced control and features

The Pegasus‑T includes a high‑resolution display and advanced control capabilities:

• > Multi‑loop control with autotune
• > Programmable temperature stepping
• > Offset elimination using an external reference probe
• > Ethernet interface and I‑Cal Easy Log software
• > Continuous USB data logging
• > Integrated webserver for remote access

Each unit includes a Type R reference thermocouple (935‑14‑91).

Thermal performance

The Pegasus‑T offers stability of ±0.05 °C at 150 °C and ±0.08 °C at 1100 °C, with a heating rate of 25 °C/min. Cooling from 1200 °C to 800 °C takes 50 minutes, and to 200 °C 180 minutes, with significantly reduced times when using the optional air cooling adaptor.

The Isotech Pegasus‑T is a unique high‑temperature calibrator engineered specifically for short sensors that cannot be calibrated in conventional furnaces. With its dynamic heating zone, flexible control options and fully customizable inserts, the Pegasus‑T provides an unmatched solution for industries requiring accurate calibration of compact temperature probes.