Compressor Emergency Shutdown Root Cause Analysis
The compressor emergency shutdown system (ESD) has tripped the natural gas compressor off-line three times in the past 24 hours.
Practical Questions
In Practical Instrumentation Questions section, you will get industry related technical questions with problem solving approach,
Solenoid Valves Practical Problems
Suppose this valve control system has a problem. The control valve (LV-104) does not move to the full-open position as
Troubleshoot Allen Bradley PLC Logic
A engineer needs to write a program for an Allen-Bradley CompactLogix PLC to control a pressure relieving solenoid valve in
Liquid Flow Control Loop Controller Action
A liquid flow control loop consisting of a flow transmitter (FT) to sense liquid flow rate through the pipe and
Motor Trip Logic using PLC Programming
Programmable Logic Controller (PLC) Questions and Answers This PLC is being used to start and stop an electric motor, and
PLC Pump Permissive Interlocks
The following PLC program was written to control the operation of a large electric motor-driven pump. A variety of “permissive”
PLC Electric Motor Interlocks
Programmable Logic Controller Questions and Answers The following PLC program was written to control the operation of a large electric
Solenoid Valves Questions & Answers – 4
Sketch arrows next to each of the two solenoid valves showing the directions of air flow in the energized (E)
Solenoid Valves Questions & Answers – 3
Determine the “normal energization” states (e.g. NE or NDE) of each solenoid valve in this diagram, assuming the process valve
Solenoid Valves Questions & Answers – 2
Solenoid valve SV-92 plays an important role in this compressor inlet separator control system. Level control valve LV-92 opens up