4-wire Transmitters Current Loops
4-wire (“self-powered”) Transmitter current loops DC electric current signals may also be used to communicate process measurement information from transmitters
Common
Study the common instrumentation and control engineering topics to upgrade your knowledge in industrial control systems and field instruments.
Field Instrumentation Tips
1. For RTD Pt 100 measurement,measure the resistance across the white and common terminal, then the temperature can be calculated
What is a Cable Gland ?
Defining Cable Glands A device designed to permit the entry of a cable, flexible cable or insulated conductor into an
Strip Chart Recorder Working Principle
A chart recorder is an instrument used to record various process and electrical signals. The most traditional chart recorders record data on
Good and Bad Wiring Practices
Good and Bad Wiring Practices If you ever find yourself working at a facility where you witness something as awful
Pressure Regulator with Flapper-Nozzle Principle
Pressure Regulator with Flapper-Nozzle is nothing but a I/P converter. Flapper-nozzle principle: The electromagnetic field changes the space between flapper
Hysteresis
A detrimental effect to feedback control is a characteristic known as hysteresis: a lack of responsiveness to a change in
Dead time
Lag time refers to a damped response from a process, from a change in manipulated variable (e.g. control valve position)
Multiple Lags (orders)
Simple, self-regulating processes tend to be first-order: that is, they have only one mechanism of lag. More complicated processes often
Lag time
If a square-wave signal is applied to an RC passive integrator circuit, the output signal will appear to have a