K Type Thermometer Data Logger 4 Channels Thermocouple Thermometer Digital Temperature Logger with 2 Thermocouples and SD Card, Programmable High/Low Limit Alarm Temperature Recorder

The media could not be loaded. NUTSHELLThis is a decent thermometer, and I'm happy with it.BASIC FUNCTIONS- show you up to four connected temperatures- show you two connected temperatures and *the difference between them*. This is called relative mode.- record up to four connected temperatures- have a beeping alarm go off if temperature goes above or below preset limits. High and low limits are independently set for each channel.ACCURACYThe thermometer gave readings similar to other thermometers that I have in the lab. See the picture (note that the thermocouple in channel 1 is one I already had, and the thermocouples in channel 2 and 3 are the ones included with the set).For more precise tests, I used the two included thermocouples and two thermocouples that I already owned, taped them into a small vial of water, and did a variety of tests. See the included graphs.When I boiled the water in a toaster oven, the thermocouples that came with the thermometer were noisier than my own, but otherwise they worked as well as mine, down to -78 C and up to 150 C.If you look at the low-temp test graph, you can see that all four readings were in sync with each other as they captured the on/off cycle of the cryo-freezer, but the readings differed on the actual temperature by about 2-3 C. The thermometer has an OFFSET FEATURE that can correct for this, automatically raising or lowering each individual channel by whatever value you set, in increments of 0.1 C. Notice, though, on that graph, that the offset you would have needed to make the yellow and red lines overlap is different at different timestamps.Several times glitches happened, as can be seen in the high temps graph, the green data. (Both yellow and green data came from thermocouples in the same glycerol vial, but the yellow gave a smooth, accurate heating curve, while the green data jumped around semi-randomly). These glitches happened with both the included thermocouples and my own. The glitches seemed more likely to happen in channel 3 and channel 4, but I didn't do enough tests to be sure of that pattern. Some of the glitches were definitely from thermocouple placement (such as being in contact with metal somewhere between the thermometer and the test vial), although at other times I couldn't find anything definitely wrong with placement. There's not quite enough evidence for me to conclude that there's anything glitchy about the thermometer itself. In practice, I'm confident that as long as the initial setup and beginning readings show no glitches, it will continue to not have glitches if I don't move things around. I've left the thermometer recording temperatures continuously for the past month, for my current scientific experiment, and every time I glance at the display, the temperatures are on track and not glitchy.RECORDINGThe thermometer CAN record in either C or F. It canNOT record in relative mode, when it's showing two temperatures and calculating the difference between them.The display automatically turns off when recording starts, but you CAN turn it back on, by **pushing the max/min button**. (But see the note on handling; it usually takes me several tries to get this to work.)As one would hope, the thermometer stays on during recording; that is, the auto-shut-off feature auto shuts off (but returns after recording is ended). I used a power cord (NOT INCLUDED) rather than test how long the included batteries lasted.Recorded temps are saved to the SD card in the form of .txt files. When I import them into GoogleDocs, it separates them into the following columns:MN/AT datetimeint1ch2ch3ch4chunitIt is slightly annoying that the import process doesn't separate the MN/AT column (manual vs automatic) from the date column, but such is life. "int" is the time interval that you told the thermometer to record at, which makes it redundant with the actual time values, but who cares. "unit" is C or F.When I recorded temps for 3 hours, 5 minutes, and 28 seconds, it produced a file that was 735 kb. At this rate, I could record continuously, every second, for 3.8 years before filling up the included 8 GB SD card.--recording modes--Automatic- happens when you press the record button- continues until you stop it- records at whatever interval you have picked in settings [options include 1, 2, 5, 10, 15, 30 sec, and 1, 2, 5, 10, 15, 30, 60, 90 min]- settings includes a way to do a delayed-start recording (which the manual calls "reservation")- files are saved as month-day-hour-min, like "03211344.txt" for a recording that began on Mar 21 at 1:44pm.Manual- happens when you press the memo button- continues until you let go of the memo button (if you hold it down, it seems to record every 2 sec)- file is saved with a name like "azoo1", with all manually-recorded temps going to the same file- I *think* you can record using the memo button while an automatic recording is going, but I did those tests a month ago and now my memory is fuzzy on that point. This is potentially useful for marking a timestamp when something interesting is happening, without interrupting the automatic recording.HANDLING/FEELButtons have to be held longer than you expect. A quick press won't do anything, even if you hear the click; it's more like a 2 second hold to "press" a button. See the video. (And maybe 3-4 seconds to "hold" a button.) Getting this timing right often takes me a couple tries. It's annoying, but not the end of the world.The plastic doesn't scream "I'm going to outlast the apocalypse", but if I'm not rough with it, I expect it to last just fine.Navigating the settings menu is relatively straightforward:- HOLD Rel/Set to enter menu- Up/down to navigate options- Enter to look deeper into an option- PRESS Rel/Set to back up a menu level- HOLD Rel/Set to exit menuReading some of the menu items is tricky; the "nn" for "minute" really threw me for a loop. (See picture). But these can be deciphered with reference to the instructions. The basic menu options are:1. recording- 1.1 recording interval- 1.2 record at later date2. alarm (high/low, per channel)3. offset/correction (per channel)4. date/time5. unit (C/F)Note that the date is set in year-month-day format, so Mar 21, 2024 is written as "24-03-21".Most minor point of all:In the settings, if you're on "ch3" and hit down, my intuition says that it should go to "ch4", but instead it goes to "ch2". Maybe your intuition visually lines numbers up with 1 starting at the bottom instead of the top, and thus matches what the thermometer does?And that's basically it. Overall, a good thermometer that I'm happy with, despite a few quirks.

Purchased this to monitor temperatures overnight. It works fairly well. Another reviewer commented that you cannot see temperatures while recording - this is not true. When you start recording, it turns off the display to save battery, but you can turn it on by pressing the "down" button. It saves to SD card, which was included. Only included 2 thermocouples, and they are not the best quality, but it seems to work okay for my purposes.

I use this to monitor AC vent temperature, intercooler reservoir temperature, air coming out of turbos and air existing intercooler. It is simple and it works, I have it stuck to my dash with dual-lok. I bought 6, six foot type K thermocouples and monitor things while driving. I use this in a very fast Stage II Buick GN.

Performed as expected. Some difficulty in programming, instructions cold be clearer. But overall satisfaction with recording results was good. Can recommend.

Nice unit. The issue is it does not display the temp when you log data. You can either see the temp on the screen, or log data. But you can't do both. So dumb.

I am slowly working my way through the operation of this data logger. The user manual is useless as the print is too small for me to read even with a magnifier. I am also trying to find a PDF file on line that I can download. No success there. Very frusterating.

It works great

I really like the way this is made and put together. Talking absolutely top quality build, I was very impressed. Came with an actual Sandisk memory card, which is nice. Overall, this is a fantastic way to gather up to 4 temperature data points.The things I wasn't that impressed with is, first, only coming with 2 thermocouples. I mean, why? This isn't a "starter unit", people aren't buying this as a "stepping stone". It's bought to perform a function. And thermocouples aren't that expensive. Just put 4 in there, for Pete's sake.And second, I'm not at all impressed with having to feed this thing AA batteries. And I also don't want to come check it one day and find the batteries have tanked, leaked, and ruined the data logger. If I was the lead on the design team of this? Instead of 4 AA batteries? It would have been powered by 2 18650 LiPo batteries, and it would have had a USB C plug-in which would both run the logger and charge the batteries. This could be made to run off 2 18650's and you wouldn't have to change a single circuit. Stick a diode in it and a charge port.In all, it's a valuable tool that, once you figure out the setup, can provide you with all kinds of useful temperature data. I just wish it was powered by something other than AA's...and included enough thermocouples to actually do what it's designed to do. 4 stars, make sure you order a few extra thermocouples when you order this. Amazon sells many of them.