UMLIFE 2PCS Temperature Controller -50 to 110 Celsius (-58 to 230 F) DC 12V Programmable Heating/Cooling Thermostat Control Switch Module NTC Waterproof Sensor Probe Dual Color LED Display Monitor

The instructions and diagrams have some English... I wired 12volt DC fan and was able to test it quickly. Seems to work like a normally open relay. Adjustment was simple, hit set, then top bottom increases and bottom button decreases the target temp. I set to 75 and used a candle to trigger a change. Fast response.

Wiring and instructions are a little complicated, but is installed and working perfectly. Very pleased. Longevity is yet to be determined 😉

If you need a basic and cheap temperature controller, this one isn't half bad. I'm using it on a Chinese mini excavator to control a 12 volt fan on the hydraulic cooler. It comes defaulted cooling mode, so you pretty much just hit set, select your target temperature, and it will turn on a few degrees above that set point using the default settings. I knocked it down a star since as other reviewers have mentioned, if you hit both buttons at once, it resets the device. I also wished it had a more robust terminal block, but for the price, it's not bad and it's working as intended. I also deducted since it comes with a very short NTC thermistor. I had to buy a three pack of 1 meter NTC sensors to be able to reach the hydraulic cooler where I wanted to measure the temperature. Those sensors are cheap and it's plug and play with a small 2-pin connector.

Excellent solution to monitor mobile audio amplifier temperatures and turn on fans at a set limit. These are also much more affordable than solutions sold by some mobile audio vendors for the same performance. Their products look fancier to if you are competing in shows then go for the more expensive ones. For my personal use, these are an excellent choice. The amplifiers are mounted under my front seats. The cable from the sensor is not long enough to reach my dashboard so I can’t see the temp while driving but the important function is its ability to turn on a cooling fan when needed,

I orderd two sets of these Temp switches a while ago for a project I just got around to building. When I took the new units out of their sealed packages, one was DOA and the other failed with a bad temperature sensor connection on the circuit that I could not find or fix. If I flexed the board, it would work. Therefore, I opened the second package of two and one of those was DOA and the second failed within one day of operation. Of course, I have had them too long to return for credit. Last week, in order to get my two unit project working, I ordered another two set package and both of those worked out of the box with one having now been installed for several days with no problem and the second on the self as a backup. Maybe I just got part of a bad batch and they are shipping reliable units now. These units have instructions that are small, hard to read and mixed with Chinese. But after a while playing with them proved that they do what they advertise as long as they keep working. They are flexible as they have many programming features. They also retain all of their settings when power is disconnected which is a must for devices like this. I will add this: In my application, I need to remote the temp sensor diode about 65 wire feet away. The unit has a +/- 15 Degree correction setting which I almost used all of it to calabrate to an accurate reading. But it is working well however, any much more than that may not calibrate properly. I used a 22 gauge shielded pair wire to remote the sensor and needed to connect the sheild on the display end to the 12 volt negative side to stablize the readings. The sensor end cable shield end I left unterminated. I would suggest, if you only need one, order the 2 Pack. If you need two or more, perhaps you should order the 5 Pack. Since they were very inexpensive for what they do, I guess you get what you pay for!

Use the too run computer fans on Solor equipment

5 stars for me being an official rocket scientist to figure it out. to save others about 2 hrs, let me tell you how to wire it when using a 12V battery and 12V computer fan. battery + goes to the first terminal, battery - to the second terminal, a jumper between battery + and the third terminal, and then the fan negative goes to the battery negative and the fan positive to the 4th terminal

1 of the 2 was DOA, and the one that was working, it was so darn loud whenever the heat was triggered, It kept waking me up. I'm a light sleeper, but dang, not that light. I didn't have trouble with the instructions, because I just looked at it's competitor's diagram. If you're still having trouble with it, this is how you wire for 12V powering both device and controller Slot 1 +VCC: 12V+ and your device you want to power +. Slot 2 GND: and S1 shares 12V- Slot 3 S2: and GND shares 12V- (TIP: You can use fork spade connector to connect 12V- to bother slot 2+3) slot 4 Load-: and this is where you plug the other device's power -. Anyways, it was so loud, and since one of it was already DOA, I returned it and got C*****'s brand's. This *oliao brand's is bigger than this one. but it doesn't make any noise, and they both seem to work. and the setting's slightly easier since you're not doing Konami code with just 2 buttons within 3 seconds. I usually don't like to return, but this one I'm glad I did.