Thermocouples are devices that measure the temperature of a system. These are made of two different metals, which are electrically connected together on one end with the other end open. The basic principle is that when the connected ends change their temperature, a voltage difference is generated on the other end. By monitoring the voltage difference at the open end, you get an accurate value for the temperature. Here are the benefits of using thermocouples over other measurement instruments:
Wider Temperature Sensing Range
Out of all the temperature measurement designs available, the thermocouple has the widest range of temperature measurements for a single device. Some thermocouples can measure from -200 degrees Celsius up to around 350 degrees Celsius. For other instruments, you may have to purchase multiple instruments to cover the same temperature range. Having a wide range like this one may mean a slightly lower level of precision. However, modern thermocouple designs, such as those at Pyrosales Thermocouples, have tolerances that are within the requirements of most industrial applications.
Higher Heat Measuring Limits
For measurement of temperatures in high heat setups such as furnaces and ovens, nothing can beat the capabilities of thermocouples. For one, thermocouples are the only common instruments that can measure temperatures reaching up to 2,500 degrees Celsius. Other modern designs have been manufactured that can withstand temperatures up to 400 degrees. Beyond that, however, thermocouples are the only devices that can reliably function at much harsher environments.
Quick Response
While other designs can produce better precision of measurement, thermocouples are still faster and more sensitive. For applications wherein you need to monitor quick changes in temperature, the thermocouple design is still the best design to deliver real-time results. On some occasions, thermocouples have responded almost three times faster than other designs.
Cost-Efficient
Due to their simplicity of design and installation, thermocouples are the least expensive option even for sophisticated machines. Manufacturing of thermocouples is relatively simple compared to other designs. Thermistor and RTD designs will need to catch up in terms of manufacturing and design to become more cost-effective when very high precision is not required.
Self-Powered
Due to their operating principle, thermocouples don’t need an external power source to deliver measurements. The voltage difference is measured and converted to temperature values. In contrast, thermistor instruments, which are based on resistance measurements, still require the machine to deliver electrical current to measure the resistance change. This measurement, in turn, must be converted into temperature values.
Rugged
Another result of its very simple concept and construction is that thermocouples are virtually indestructible compared to other measuring devices. For aggressive environments such as steel foundries and factories, excessive vibration and abuse will quickly deteriorate other instruments. At the same time, thermocouples can withstand years of vibration and abuse with minimal damage and change in accuracy.
Conclusion
If your company is currently looking for the best temperature measuring devices, purchasing thermocouples will save you more money in the long run because thermocouples cost less to manufacture. Depending on how many probes your operation will need, the cost of thermocouples is a major factor to consider. Even if thermistors can give you more accurate readings, thermocouples will be able to address most of your basic temperature reading needs.
