PT100 shows a negative value! !
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The actual temperature is 36 degrees, but the PT100 only reads 78 degrees...! The temperature is negative...! Could you tell me what problem this is? !
Reply to 1# crazemuse: Try turning off the power and then connecting it again; this has happened to us a few times, but in the end the display gets damaged. Hehe, which watch is that? Check the resistance of each resistor, take a look
The resistance of the lane-changing is too high. You can find out by using a multimeter.
I suddenly lost connection at the connector of the meter head, while measuring…
Can a temperature of 78 degrees still be negative? ? ?
It should be 78 ohms, haha； Pull out the core and give it another try
The PT100 has a problem; let’s replace it with a spare part.
Is it short-circuited? Check if the junction box has water inside it
The original poster had better describe the problem in language that everyone can understand; your Mandarin is too poor.
That negative value is likely an invalid one. What is your range? It’s usually between -50 and 450
:Lol, it was edited in a hurry on my phone, so there are some mistakes in the sentences; please forgive me. :Lol, after removing the thermometer and placing it in the office, the resistance measured was 78 ohms (according to the table, this corresponds to -50 degrees). The resistance between A and B, as well as between A and C, was 78 ohms each; the resistance between B and C, since they are on the same line, was zero.