2 wire transmitter current loops

2-wire Transmitters Current Loops

2-wire (“loop-powered”) transmitter current loops It is possible to convey electrical power and communicate analog information over the same two

Four Wire Current Loop

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

Field Instrumentation Tips

Field Instrumentation Tips

1. For RTD Pt 100 measurement,measure the resistance across the white and common terminal, then the temperature can be calculated

Cable Gland Parts

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

Hysteresis - 2

Hysteresis

A detrimental effect to feedback control is a characteristic known as hysteresis: a lack of responsiveness to a change in

temperature sensor

Dead time

Lag time refers to a damped response from a process, from a change in manipulated variable (e.g. control valve position)

control of level in three cascaded Loops

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