How to measure the measurement accuracy of pt100 temperature sensor

The components we often use for temperature detection mainly include thermal resistance and thermocouple. Their common feature is to use a multimeter to measure whether the two output terminals (sometimes multi-terminal) are connected (although there is a certain resistance value). If the circuit is open, it will be broken. This is the first step when actually judging the quality. The resistance value of thermal resistance is certain, such as PT100 normal temperature around 110 ohms, CU50 normal temperature around 55 ohms.

The output of thermocouple is voltage value. Under a certain temperature, it will output a voltage signal of several to tens of millivolts, which can be measured by the voltage range of a multimeter. The output voltage of the thermocouple is only a few mV, depending on the accuracy of the multimeter. The digital multimeter can be roughly measured to judge the quality. The output of the thermocouple is in the millivolt level. It is impossible to detect its output with a multimeter, but it can be measured on and off. In most cases, as long as the galvanic part (at the fusion point of the two wires) is open, not oxidized or broken, it is generally no problem.
So it can also be taken out of the sheath for visual inspection. To really check, it is necessary to use a standard thermocouple to compare and measure its output millivolt value. This must be done by personnel engaged in measurement.