Thermocouples are widely used in temperature measurement of various objects and automated monitoring and control systems. Temperature measurement with thermocouples is popular because of its simple, robust sensor design. Thermocouples allow operation over a wide temperature range and are very cheap. In general, some pluses. So how do you connect a thermocouple and measure the temperature of the target object?
Instructions
Step 1
Connect thermocouples to devices using special thermocouple (compensation) wires. They must be made of the same materials as the thermocouple itself. You can also use metal wires with thermoelectric characteristics that will be similar to the characteristics of the electrodes of the thermocouple itself. Observe the polarity when connecting the compensation wires to it.
Step 2
Shield the communication line between the sensor and the instrument. This will help to avoid the harmful influence of noise on the measuring part of the thermocouple. Use a grounded steel pipe as a shield. If this condition is not observed, then there may be significant errors in the measurement.
Step 3
To measure the temperature of the computer processor, drill the heat sink exactly in the center and install the sensor exactly there. At the same time, ensure that the sensor is pressed using any available means. You can use glue and fix it in this way, but it can be difficult with this option. There can also be problems with the thermal conductivity of the radiator, so this method should be used as a last resort.
Step 4
Connect an electronic measuring system or a measuring device to the ends of the thermoelectrodes or to the gap of one of them. The thermocouple is combined with an electrical measuring device to form a thermoelectric thermometer. In places where thermocouple conductors are connected, thermoEMF appears. They act on the input of the measuring system, and the sum of the signals comes from the working thermocouple and from those "thermocouples" that have arisen at the connection points.
Step 5
To avoid this effect, it is necessary to constantly maintain the cold junction temperature. Its temperature must be measured with another sensor, and then the thermoEMF value must be subtracted from the thermocouple signal.
