Thermocouple Properties, Temperature Ranges, Element Construction
Thermocouple Applications : (J)–Iron vs Constantan (Most Common) May be used in vacuum, oxidizing, reducing, and inert atmospheres. Heavier gauge wire is recommended for long term life above 1000°F since…
Types of Thermocouple Measuring Junction
Types of Thermocouple Measuring Junction There are four types of thermocouple measuring junction constructions : Grounded Thermocouple Junction Ungrounded Thermocouple Junction Exposed Thermocouple Junction Isolated Thermocouple Junction Grounded Thermocouple Junction…
RTD Standards
RTD Standards A resistance temperature detector or platinum resistance thermometer works on the principle that the electrical resistance of a metal changes in a significant and repeatable way when temperature…
What is IEC 61508 ?
What is IEC 61508? IEC 61508 (previously IEC 1508) is a seven-part standard that defines specific direction and guidelines on the functional safety of electrical/electronic/programmable electronic (E/E/PES) safety related systems.…
Instrument Turndown Ratio
Instrument Turndown Ratio An important performance parameter for transmitter instruments is something often referred to as turndown or rangedown. “Turndown” is defined as the ratio of maximum allowable span to…
Logic Gates in PLC Ladder Logic
Logic Gates in PLC Ladder Logic We can construct simply logic functions for our hypothetical lamp circuit, using multiple contacts, and document these circuits quite easily and understandably with additional…
How to Commission WirelessHART Transmitter With Gateway
WirelessHART Transmitter With Gateway This guide is intended to give an idea on how to use 375/475 Field Communicator to configure Rosemount wireless device to be connected to wireless gateway…
Calibration : Up-tests and Down-tests
Calibration : Up-tests and Down-tests Instruments are calibrated to measure the process variables in a fixed range of scale. All instruments are assumed to be Linear if the physical quantity…
Error sources creating uncertainty in Calibration
Through measurement, we try to obtain the value of an unknown parameter. However this measured value cannot be the actual or true value. If the measured value is very close…
As-found and As-left Documentation during Calibration
As-found and as-left Documentation during Calibration Calibration is the comparison of a measurement device (an unknown) against an equal or better standard. A standard in a measurement is considered the…
