There are two standards for platinum RTDs: The European standard and the American standard. The European standard, also known as the DIN or IEC standard, is considered the world-wide standard for platinum RTDs.
Thermocouples are designed for use in areas where the temperature changes are rapid and so require a sensor capable of tracking these sudden changes accurately and reliably.
Temperature Sensor are the instruments which measures the temperature . A temperature sensor is a device that measures temperature and is more commonly known as a thermometer.