The Tegam 931B Data Thermometer is an industrial-grade tool for measuring and logging temperature data. It can be used by itself or in conjunction with an app that runs on a smart phone, either Android or Apple. The phone app also acts as a bridge to a cloud repository for measurement data that can be retrieved as needed.
The thermometer electronics are contained in a hand-held case that provides control buttons and a connector that accepts the thermocouple probe. The unit can operate with virtually all types of thermocouples. The unit we tested, the 931B, has one probe connector; the 932B is a two-channel instrument. Many different probes are available that can address almost any measurement challenge. The main unit updates its temperature reading three times per second. It can store one reading every second, or fewer if desired. The cloud can be updated every five seconds or less frequently if desired. Power is supplied by three AA batteries that the manufacturer claims will last 1000 hours.
Using the Tegam 931B Data Logging Thermometer App
The hand-held unit has an initial setup procedure that allows the user to select the thermocouple type and the temperature scale, either F, C or K. After setup, the large display shows the temperature, date, time, and the status of data collection. There is an internal memory that will hold roughly 1000 data points. When the app is used, the data is uploaded to the cloud, which will hold essentially unlimited data.
The app mimics the hardware’s display and control buttons. The connection is via a low-powered Bluetooth link that the manufacturer claims is good for about 30 feet (~9m) separation. While connected to the device, the app will relay data to an account created by the user on Tegam’s cloud server, where the data is stored and accessible for download and graphing. Multiple devices, identified by their serial numbers, can be associated with a single account. The cloud can also identify a given unit and associate it with a location or locations defined by the user.

Quality
The supplied probe appeared to be one designed for general usage. Other available probes have small diameter tips that might respond more quickly than the supplied probe, although its performance was very good. The probe’s stainess steel cable is the most robust one I’ve ever seen – true industrial grade!
While this unit can certainly be used by a cook to measure food temperatures, it is really designed for data collection on a large scale. That means it could be useful for monitoring temperatures over long periods of time in, say, an abattoir or an extended food processing chain. The package with a probe and carrying case will set the buyer back well over $400. This makes it a very expensive choice for simple measurement tasks. That said, some folks just like to have fancy toys, so you be the judge.
Warranty
The thermometer comes with a two-year calibration guarantee and a three-year warranty. Contact info for the company is found in the accompanying documentation. The product is made in the USA.
Our Review of the Tegam 931B Data Logging Thermometer
Build quality and performance are first rate. I don’t usually test data loggers, so I’m not well-versed on all the features desired in these devices. I’ll leave it to the reader to explore the manufacturer’s website, tegam.com, for futher information. I’m giving this unit a Gold Medal for quality and functionality, despite the high price for features that may not be relevant to the average home cook.