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Joel Don
345 Results Found
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FeatureAutoQuiz: Unique Feature of a Pneumatic Differential Pressure Sensor/Transmitter
In a pneumatic transmitter, the nozzle faces a baffle, so, as the measured pressure increases, the baffle moves toward the nozzle. -
FeatureAutoQuiz: What Is the Definition of Restore Time in Industrial Maintenance?
The restore time includes all activities required to diagnose and repair the device. This includes diagnosing the problem, isolating the device from the system, traveling to the device, and repairing -
Feature
AutoQuiz: What Is the Condition When Controller Output Increases in Conjunction With a Controlled Variable Increase?
As pressure increases (controlled variable), the valve output would increase to open the valve in order to relieve the pressure. -
NewsBook Excerpt + Author Q&A: Fluid Mechanics of Control Valves
ISA's up-to-date work on final control valve elements presents theoretical and practical information in an easy, conversational style, -
Feature
AutoQuiz: How to Program the Correct PLC Equation for a Pressure Transmitter
To scale the analog input, calculate the "% of the raw counts range" that is represented by the analog input, and multiply by the EU100% range, since the EU0% value is 0. -
Feature
AutoQuiz: How to Perform PLC Raw Count Calculations for Pressure Transmitters
A pressure transmitter is connected to the analog input card of a PLC. The 4-20mA input value from the transmitter is converted into equivalent raw counts. -
FeatureAutoQuiz: What Is the Purpose of an Optical Isolation Circuit on a Digital Input Card in a PLC I/O System?
An optical isolation circuit is used to provide a barrier between the field wiring & associated field wiring issues (shorts, ground loops, transients, etc.) -
FeatureAutoQuiz: What Is the Best System for Analyzing Multiple Sources of Data in an Industrial Plant or Facility?
A well-designed, integrated building automation system seamlessly integrates lighting, elevators, boilers, chillers, fire protection, generators, access control, and HVAC control systems, which may al -
Feature
AutoQuiz: How to Convert a Transmitter's Current Output Signal to a Voltage Input Signal
Place a resistor across the input terminals of the controller to convert a transmitter's current output signal. -
Feature
AutoQuiz: What Flow Sensor Naturally Generates a Pulsed Output to Represent Flow Rate?
Turbine meters almost universally use a magnetic pickup to determine the number of rotations of the spinning turbine element. -
FeatureAutoQuiz: What Information Is Typically Included in a Loop Diagram?
Tag numbers, wire numbers and terminal numbers, and indication of the interrelation to other instrumentation loops, are the essential elements of a loop diagram. -
FeatureAutoQuiz: What Is the Purpose of Forward Decoupling?
A forward decoupling algorithm can be used to cancel out MIMO interactions, making more traditional control methods applicable to complex systems. -
Feature
AutoQuiz: What Is the Minimum Course of Action to Take Before Replacing Damaged Wiring?
All circuits to be worked on should be tested with a multi-meter prior to performing work to ensure that no voltage or current is present. -
FeatureAutoQuiz: Which Flow Measurement Device Does Not Require Square Root Extraction?
The output from a magnetic flowmeter is a linear signal that is proportional to the velocity of the flowing fluid. -
FeatureAutoQuiz: What Is the Purpose of a Valve Positioner?
A valve positioner adjusts the pneumatic output to a valve actuator so that the requested position of the valve from a controller is achieved. -
Feature
AutoQuiz: Models of Control to Describe a Batch Process
A process stage in the process model can be mapped to a unit procedure in the procedural model, which in turn is mapped to a unit in the physical model. -
Feature
AutoQuiz: Which Type of Electrical Wires Would Normally Be Shielded in Control Systems?
Cable shield, connected to an isolated zero potential, is required to prevent nearby inductive loads and EMF fields from altering the low-level voltage or current levels in the signal wiring. -
Feature
AutoQuiz: What is Common Mode Noise?
Common noise must be in phase between conductors, or it converts to normal mode or differential noise. -
FeatureAutoQuiz: What Happens When a Controller Receives an Error Signal for Significant Periods of Time?
The integral term of the PID control algorithm increases (or decreases) at a rate inversely proportional to the integral time of the controller. -
FeatureAutoQuiz: What Are the Advantages of Cascade Control?
Cascade control does very little to improve upon control loops that were previously stable. Examples are liquid level and gas pressure control loops. -
FeatureAutoQuiz: Characteristics of a Flowmeter
For a turbine flowmeter, the rotor is supported by the hubs and bearings inside of a flowmeter body, and as the rotor spins, the number of revolutions is determined with a magnetic pickup. -
FeatureAutoQuiz: How to Measure the Temperature Between Two Dissimilar, Joined Metals
A thermocouple contains two different conductors that produce a voltage proportional to a temperature difference between the ends of a pair of conductors. -
Feature
AutoQuiz: How to Measure Fluid Velocity Through a Pipe
The constant between pipes of differing diameters is the flow rate (and other fluid properties) is the same in both pipe lengths. -
FeatureAutoQuiz: Design Specifications for Building Automation Systems
Energy management, access control, lighting control, asset management, communications, life safety, fire alarm, and HVAC controls are all of interest when designing a building automation system -
Feature
AutoQuiz: What Is the Continuous Sequence of Steps Performed by a PLC Processor?
The time it takes for the PLC to complete its scanning of all program steps in one operating cycle is called the scan time. -
FeatureAutoQuiz: What Network Security Technology Does Not Use Encryption?
A virtual local area network (VLAN) is achieved through configuration of Ethernet switches and not encryption. It divides a physical network into smaller logical networks to increase performance, impr -
Feature
AutoQuiz: What Is the Purpose of the Proper Grounding of Electrical Devices?
Proper grounding provides safety, over-current protection, electrical noise reduction, lightning protection, and static electricity reduction. -
Feature
AutoQuiz: How to Calculate the Pressure Recovery Factor for Valves
Pressure recovery factor is the increase in fluid static pressure that occurs as fluid moves through a valve from the vena contracta to the valve's outlet and downstream piping. -
FeatureAutoQuiz: What Are the Four Key Activities in the Maintenance Cycle of a Control System?
Documentation of the "as left" condition of the control system is a basic requirement for all maintenance, calibration, commissioning, and testing tasks. -
Feature
AutoQuiz: What Are Multiple Independent Protection Layers in Relation to Industrial Safety?
A consequence of the concept of multiple independent protection suggests minimization of risk occurs when safety instrumented systems are completely independent from process control systems. -
FeatureAutoQuiz: What Is the Response in Level Control System If the Process Liquid Medium Changes?
For a capacitance probe installed in a metal tank, the measured level is proportional to the measured capacitance between the level probe (one capacitor plate) and the tank wall (second capacitor plat -
FeatureAutoQuiz: How to Determine Cause of the Apparent Discrepancy in Flow
Periodic visual inspection of orifice plates is required to ensure the integrity of measurement with a digital flow transmitter. -
FeatureAutoQuiz: Which Flowmeter Type Does Not Operate on the Principle That a Differential Pressure Is Developed Across a Flow Restriction?
A Coriolis flowmeter develops a flow measurement by measuring the degree of deformation (twisting) of a vibrating tube(s) as the fluid moves through the tube. -
NewsBook Excerpt + Q&A: Safety Instrumented Systems, A Life-Cycle Approach
This book leverages the performance and documentation requirements defined in the ISA/IEC 61511 functional process safety standard coupled with the authors' nearly 80 years of safety system experience -
FeatureAutoQuiz: What Is an Example of Adaptive Control?
A controller uses a quantitative process model and modifies controller tuning based on how the process responds in relation to the model prediction. -
FeatureAutoQuiz: P&ID Determination for Temperature and Pressure Sensors
Instrument technicians often use P&ID diagrams as a reference to identify what type of instrumentation is installed and how the instrumentation is installed in the process. -
FeatureAutoQuiz: What is Tree Topology in Fieldbus?
Tree Topology concentrates the connection of several field devices to couplers/junction boxes. Tree topology is also known as "Chickenfoot" or "Star" configuration. -
FeatureAutoQuiz: What P&ID Symbol Is Used to Indicate a Temperature Regulator?
The symbol reflects a temperature regulator, filled thermal system. -
FeatureAutoQuiz: How to Assess the Optimal Alarm Deadband Setting
Learn to assess the alarm deadband setting on a high alarm. -
FeatureAutoQuiz: What Is the Purpose of an Intrinsic Safety Barrier?
An intrinsic safety barrier prevents excess voltage and current from reaching the hazardous area. -
Feature
AutoQuiz: How to Assess the Hazard/Risk Category for an Industrial Electrical Panel
Work on energized electrical conductors and circuit parts, including voltage testing on panelboards, or other equipment rated 240V and below would be classified as Hazard/Risk Category 1. -
NewsBook Excerpt + Q&A: New Edition of Guide to the Automation Body of Knowledge
ISA's book is a key resource for preparing for certification, including the ISA Certified Automation Professional, the ISA Certified Control Systems Technician, and the Professional Engineer (P.E.) ex -
FeatureAutoQuiz: How is the Reynolds Number Used in Flow Measurement?
For the Reynold's number, the inertial forces in the numerator are given by the product of mass (density), fluid velocity, and pipe diameter. -
FeatureAutoQuiz: What Is the Best Tuning Method for a Catalyst Feed Flow Controller?
Only a closed-loop tuning method can be used with an exothermic reaction where the reactor can "run away" (increasing speed of reaction as the reaction progresses, catalyzed by its own heat of reactio -
FeatureAutoQuiz: Plotting Control Valve Characteristics
For an equal percentage valve characteristic, each increment of valve movement provides the same percentage increase in flow. -
FeatureAutoQuiz: What is the Lifecycle Economic Model?
All lifecycle costs should be considered over the entire expected life of a project, with all costs calculated on a net present value basis. -
FeatureAutoQuiz: Characteristics of a Full-Wave Bridge Rectifier Circuit
A bridge rectifier consists of diodes in a bridge circuit configuration. It features the same output polarity for either input polarity, and is used for converting an alternating current (AC) input in -
FeatureAutoQuiz: What Is the Cause of Cavitation in a Liquid Flow Stream?
When fluid drops below a liquid's vapor pressure, a gas is formed. As fluid moves downstream to where the fluid pressure is greater than the vapor pressure, it "collapses" back into a liquid. -
FeatureAutoQuiz: How to Read a Gauge Pressure Transmitter
At zero gauge pressure in the steam line, you are essentially suppressing (pushing) the transmitter output back down to zero after the system reaches equilibrium. The transmitter will read that impuls -
FeatureAutoQuiz: Failures of Complex Systems in SIS Design and SIL Selection
A fault tree analysis begins with the "top event," which is the result of a number of basic events that contribute to, or initiate, the system failure.