Isotech 17701 Low Temperature Furnace

The Isotech 17701 Low Temperature Furnace is specially designed for achieving and maintaining the fixed point plateaus of Indium (156.5985 °C), Tin (231.928 °C) and Zinc (419.527 °C) over long periods of time. These fixed points are essential references within the International Temperature Scale of 1990 (ITS-90) and are indispensable for the calibration of high-quality thermometers. The furnace provides a stable, reproducible environment in which fixed-point cells can be safely melted, frozen and held at plateau for 6 to 12 hours. This makes the instrument ideal for laboratories working with SPRTs and other precision thermometers.

Designed for fixed point realisation

The Isotech 17701 Low Temperature Furnace is a single-zone furnace, optimised for creating a homogeneous temperature field. The aluminium alloy of the furnace core ensures an exceptionally low thermal gradient over its entire length, which is essential for achieving a stable freezing point plateau. The main heating uses a parallel-tube heater, a design also used by NIST for its excellent stability and uniformity. In addition, a pre-warming tube is integrated to preheat fixed point cells in a controlled manner before the plateau is used.

Plateau control with minimal effort

Although initiating a freezing point plateau requires some operator attention, the oven then maintains the plateau almost automatically for 10 to 12 hours. This makes the instrument particularly suitable for long-term calibrations and reproducible fixed-point measurements.

Safety first

The oven is equipped with two completely independent safety systems:

> Active safety: a dedicated over-temperature controller that intervenes immediately if the set limit is exceeded.
> Passive safety: a fusible link in the main power supply line that provides protection in extreme situations.
This double safety feature guarantees safe operation, even at prolonged high temperatures.

Modern controls and improved ergonomics

The latest generation of Isotech ovens has been developed based on user feedback. The controls are located at the top for better accessibility, and an integrated SPRT stand provides secure support for thermometers.

In addition, the oven features:

> Bright colour display
> USB and Ethernet connectivity
> Programming options for melting and freezing cycles
> Storage of multiple programmes
> Logging of heating and cooling history

These features make the oven suitable for both manual and automated fixed-point procedures.

Independent and maintenance-free

The furnace is completely self-sufficient, equipped with castors and requires no external facilities except mains power. Its robust construction and high-quality components ensure maintenance-free operation and a long service life. The Isotech Low Temperature Furnace offers a reliable, safe and extremely stable solution for achieving fixed-point plateaus for Indium, Tin and Zinc. Thanks to its modern controls, programmable cycles, dual safety features and excellent thermal uniformity, the ITL-M-17701 is an indispensable tool for laboratories working to the highest standards of temperature metrology.