Continuous Flow Measurement
The Continuous measurement of fluid flow is arguably the single most complex type of process variable measurement in all of industrial instrumentation.
Temperature Sensor Accessories
One of the most important accessories for any temperature-sensing element is a pressure-tight sheath known as a thermowell. This may be thought of as a thermally conductive protrusion into a…
Thermal Imaging Temperature Measurement
A very useful application of non-contact sensor technology is thermal imaging, where a dense array of infrared radiation sensors provides a graphic display of objects in its view according to…
Non-contact Pyrometers Characteristics
An interesting and useful characteristic of non-contact pyrometers is that their calibration does not depend on the distance separating the sensor from the target object’s surface. This is counterintuitive to…
Non-contact Temperature Sensors
Virtually any mass above absolute zero temperature emits electromagnetic radiation (photons, or light) as a function of that temperature. This basic fact makes possible the measurement of temperature by analyzing…
Thermocouples Burnout detection
The most common failure mode for thermocouples is to fail open, otherwise known as “burning out.” An open thermocouple is problematic for any voltage-measuring instrument with high input impedance because…
Problems of Reference Junction Compensation : Thermocouples
Reference junction compensation is a necessary part of any precision thermocouple circuit, due to the inescapable fact of the reference junction’s existence. When you form a complete circuit of dissimilar…
Thermocouple Extension Wires
In every thermocouple circuit there must be both a measurement junction and a reference junction: this is an inevitable consequence of forming a complete circuit (loop) using dissimilar-metal wires. As…
Thermocouple Software compensation
Previously, it was suggested that automatic compensation could be accomplished by intentionally inserting a temperature-dependent voltage source in series with the circuit, oriented in such a way as to oppose…
Thermocouples Law of Intermediate Metals
It is crucial to realize that the phenomenon of a “reference junction” is an inevitable effect of having to close the electric circuit loop in a circuit made of dissimilar…
