Isotech TTI-22 High Accuracy Thermometer

The Isotech TTI-22 sets a new standard in affordable, high-precision resistance thermometry. Where this level of performance was previously reserved for specialised laboratories with expensive thermometry bridges, the TTI-22 now brings accuracy of 1 mK (0.001 °C) within reach for industrial and secondary laboratories. The instrument combines high resolution, long battery life and modern connectivity in a compact and robust housing.

High accuracy and resolution

The TTI-22 offers a resolution of 0.0001 °C and a measurement uncertainty of 0.001 °C when used with a 100 Ω PRT. The resistance resolution is 0.00004 Ω, allowing even the smallest variations in temperature or resistance to be accurately detected. The instrument supports both industrial Pt100 sensors and SPRTs (25.5 Ω and 100 Ω) according to ITS-90, making it suitable for a wide range of applications — from industrial process control to high-precision calibration setups.

Designed for reliability and long life

The TTI-22 uses a patented measurement method that automatically performs zero and gain correction with each measurement. The polarised DC measurement current is continuously switched, eliminating thermal EMFs. With its fully solid-state construction—no mechanical relays—the TTI-22 is designed for long life and minimal maintenance. The internal reference resistor has a temperature coefficient of only 0.3 ppm/°C and a stability of ±5 ppm per year, contributing to exceptional measurement reliability.

Two channels and fast measurement cycle

With two inputs, the TTI-22 can measure two sensors simultaneously, ideal for comparison calibrations or monitoring temperature differences. The measurement time for both channels together is only 1.44 seconds, making the instrument fast and responsive. For users accustomed to classic thermometry bridges, the TTI-22 also offers a ratio measurement mode, which determines the ratio between the two inputs.

Smart features for everyday use

The TTI‑22 can store up to 30 probe calibrations, including the expiry date of each calibration. The instrument automatically alerts you when a sensor needs recalibration — a valuable feature for quality assurance and ISO‑certified laboratories. Built-in statistics functions display average values, standard deviation and measurement series, making it easy to analyse stability and trends.

Compact, portable and energy efficient

Weighing only 1.8 kg and with a battery life of over 10 hours on two AA batteries, the TTI-22 is ideal for mobile use. The instrument can also be powered via a 7.5 V adapter. The rugged housing is designed for daily use in both laboratory and field environments.

Modern connectivity

The TTI-22 features RS232 and Ethernet, including a built-in web server for easy temperature viewing via a browser. The included Cal Notepad software makes monitoring, logging and graphical analysis easy. The instrument is also fully compatible with Isotech I-Cal Easy, which allows automatic comparison calibrations to be performed.

Applications

The TTI‑22 is ideal for:

> Reference measurements in combination with liquid baths and dry blocks
> Comparison calibrations with SPRTs and PRTs
> High-accuracy industrial temperature measurements
> Research applications requiring low uncertainties
> Long-term monitoring of critical processes

Thanks to its performance and versatility, the TTI-22 replaces traditional bridges in many cases, but in a compact and affordable instrument. The Isotech TTI-22 offers an unrivalled combination of accuracy, portability and ease of use. With its high resolution, smart features, modern interfaces and robust construction, the instrument is a powerful and future-proof solution for anyone working with precision thermometry. The TTI-22 delivers performance that is 5 to 10 times better than comparable instruments in the same price range — making it an exceptionally valuable choice for both laboratories and industrial users.