Leaton® Digital Thermocouple Thermometer Dual-Channel LCD Backlight Temperature Meter Tester for K/J/T/E/R/S/N Great

I think I connected wrong poles of thermocouple and that was the problem - but the return was so straightforward

Works very well and is easy to use. The plugs are a tight fit into the machine, a bit too tight but better than too loose and dropping out. All in all a very good thermometer.

Pas precis,erreur de 1 degre voir 1,2 ....a voir avec d'autres thermocouple,ceux la sont de faible qualite...je ne n'attendais pas de miracle pour le prix....si encore on pouvait le calibrer....mais non....

Right from the box I ran through the settings of probe type (=K), and Temp scale (=F) - very simple to do, and all settings remain as they were at last power-off. The room temperature initially read 73.4F and 79.1F, but after 30 seconds or so, they settled down to readings of 70.1F and 70.1F. Over the next half an hour, one reading or the other would briefly move up or down by +/- 0.1 or 0.2, but always returned to 70.1. During this time, I cycled the power every few minutes to see how the meters started back up. There was only a second or two of settling time with each power-up. I left the probe ends in place, close together and weighted down to the floor by a book. Handling the meter body had no effect on the readings. Unplugging and switching the probes made no difference. Comparing to my trusted Fluke 80T probe I have used since 1982 or so (and was last calibrated in 2007), the Fluke measured room (floor) temperature reading is 70.0F. Based on my experience with thermocouple probes supplied with various multimeters I own , this is extraordinarily stable and precise, as well as accurate at at least one point. This result is not something anyone should expect from a mass-produced thermocouple thermometer - especially an inexpensive one. Probably I was just lucky - but at least it shows that such performance is possible from this instrument. I plan to make accuracy tests with an ice bath and with boiling water, and tracking precision tests with refrigerants such as CO2 and with a hot air gun. I will use a variety of probes as well as the ones supplied. I think it highly unlikely that the two probes will track so perfectly over a wide range of temperatures, but this single point test is encouraging. I will update this review after I perform further testing. **** UPDATED**** I did some further testing, using the probes supplied. I twisted the probe ends together so they would be in the same environment. In an ice water bath The two probes read 33.8F and 34.1F after stabilizing for about 2 minutes. In my home freezer (set for -5F), The probes read -5.1F and - 4.8F. In boiling water, they stabilized at 211.7F and 211.1F. I tried to read my oven, set to 300F, but I couldn't get a stable reading. It turns out that the oven cycles on and off fairly frequently, and the temperature swings high, then low as it does and the probes can't keep up. Manufacturing variations result in the sensing beads on the two probes being visibly different in size - about 2:1 in diameter. The larger bead is much slower to settle than the smaller bead. As the temperature is swinging up and down, the difference in readings becomes large, only settling once the temperature becomes constant for a minute or so. Probably by selecting two thermocouples from the same manufacturer's batch that have nearly identical junction beads, the probes would track well. I ordered a set of ten probes to use in that way.

I saw a review of this device on YouTube: Jim's cool stuff. Thermocouple Meter Review; Can a $25 thermocouple thermometer be any good? It was a good buy.