How to Choose a Control Valve?
When choosing a control valve for a process, there are many things that must be considered, including the valve’s flow characteristic, its size, noise, the potential for cavitation or flashing...
How to Configure a Smart Transmitter Using a HART Communicator?
The following instructions describe how to configure a 2 wire Radar smart transmitter with HART communicator using an Emerson 475 Field Communicator. The 475 Field Communicator used for this article...
Determine Resistance value of Resistors
Determine the nominal resistance values of these resistors, given their band colors, and also express the allowable tolerance in ohms (i.e. what the minimum and maximum acceptable resistance values are...
Pressure Control Loop Wiring Connections
This pictorial diagram shows the wiring connections for a simple pressure control loop, where a loop- powered 4-20 mA pressure transmitter sends a signal to a Honeywell controller, which in...
pH Transmitter Problem
A newly-installed pH transmitter does not seem to be measuring the pH of the process liquid accurately. The indicating controller’s display does not match the display of the hand-held pH...
Types of Cable Trays – Purpose, Advantages, Disadvantages
Cable tray systems are alternatives to wire ways and electrical conduit, which completely enclose cables. Cable trays are capable of supporting all types of wiring: such as High Voltage Power...
Current-to-Pressure Transducer Calibration Table
Suppose you wish to calibrate a current-to-pressure (“I/P”) transducer to an output range of 3 to 15 PSI, with an input range of 4 to 20 mA. Complete the following...
Analysis of HART communicator and Smart HART Transmitter
During the 1980’s the Rosemount corporation developed a means for 4-20 mA analog signaling circuits to carry digital signals as well, so that 4-20 mA process transmitters could be equipped...
Instrument Errors – Zero, Span, Linearity
Suppose an electronic pressure transmitter has an input range of 0 to 100 PSI and an output range of 4 to 20 mA. When subjected to a 5-step up-and-down “As-Found”...
Identify Instruments in Piping and instrumentation Diagram
Identify the meanings of the following instruments in this Piping and instrumentation Diagram (P&ID). Piping and instrumentation Diagram Solution: The below Piping and instrumentation (P&ID) Diagram shows the abbreviations or...