# Shared Flashcard Set

## Details

EPRI 1
Preparation for the EPRI level 1
171
Mechanical Engineering
Professional
02/24/2019

Term
 What procedure should be enacted before working on an electrical or pneumatic system?
Definition
 Lockout/tagout
Term
 What is the total resistance of a parallel circuit with resistances of 25, 35, and 45 ohms?
Definition
 11 ohms
Term
 Who is authorized to remove each lock and tag applied?
Definition
 Only the technician who applied the lock
Term
 What should an instrument technician evaluate before opening a process line?
Definition
 The SDSs for the chemicals in the line
Term
 What is the proper ratio of rise to run for an extension ladder?
Definition
 4:1
Term
 Find the volume of a tank with a diameter of 12 feet and a height of 37 feet.
Definition
 4,183.8 cu.ft.V=(3.14)(R^2)(H)
Term
 Find the DC voltage drop across a 250-ohm resistor with a current of 16 milliamperes DC.
Definition
 4 VDCE=IR
Term
 Convert 4,500 cubic feet to gallons.
Definition
 33,662.25 gallonsGallons=(CuFt)(7.48)
Term
 Which of the following does not determine the severity of an electrical shock?
Definition
 Temperature
Term
 This vocabulary term is defined as "a system in which deliberate guidance or manipulation is used to achieve a prescribed value or variable."
Definition
 Control system
Term
 Where in the physical process would a primary element be located?
Definition
 In contact with the process
Term
 What type of control signal is characterized as an on/off signal?
Definition
 Discrete
Term
 True or False: Automatic control systems relieve the operator of the responsibility to maintain a process.
Definition
 True
Term
 Process variables in a system requiring control include which of the following? Density, Flow, Specific Gravity, or Volume
Definition
 Flow
Term
 How are inputs and outputs typically connected to the controller in a process system?
Definition
 Twisted-pair wiring
Term
 What type of signal is represented by a packet of information containing a series of discrete bits?
Definition
 Digital
Term
 What type of signal can be used as inputs to record a range of values and as outputs to position a final control element?
Definition
 Analog
Term
 What is a process?
Definition
 A system being measured and controlled.
Term
 A control valve is considered to be which element in a process?
Definition
 Final control element
Term
 A control loop that uses float switches to turn a pump on and off is referred to as which type of control?
Definition
 Discrete
Term
 What do symbols portrayed on diagrams and drawings depict?
Definition
 Instruments
Term
 What is the name of the unique identification code for devices shown on instrumentation drawings and diagrams?
Definition
 Tag number
Term
 What is a device that is identified as TT 1004?
Definition
 Temperature transmitter 1004
Term
 What is a device that is identified as PSL 2345?
Definition
 Pressure switch low 2345
Term
 What does the tag number LAL 1003 represent?
Definition
 Level alarm low
Term
 What type of drawing shows all related (loop number) devices for controlling means and the wiring path, termination point, and device locations?
Definition
 Loop sheet
Term
 What time of document indicates the specifics for which device is ordered and the type of conditions under which is must perform?
Definition
 Spec sheet
Term
 How are devices that are hidden from the operator's view indicated?
Definition
 Series of dashed lines within the tag number
Term
 A control valve that fails in position and does not move can be indicated with a graphic symbol or which letters?
Definition
 FL (Fail Last)
Term
 A relatively quick way to determine the quantity of a specific type of device needed on a project would be to consult which documentation?
Definition
 Instrument index sheets
Term
 What is the accuracy of a transmitter that has a maximum deviation of 0.18 milliampere and an output span of 16 mADC?
Definition
 1.13%Accuracy=(MaxDev/Span) X 100
Term
 What is the maximum allowed deviation (in mADC) for a device that has an accuracy requirement of 0.5% and an output span of 16 mADC?
Definition
Term
 What is the span of an instrument with a LRV of 37 inches of water and an URV of 210 inches of water?
Definition
 173 inches of waterSpan=URV-LRV
Term
 Determine the five input test points (0%, 25%, 50%, 75%, 100%) used for a temperature transmitter with calibration range of 32 degrees F to 212 degrees F and an output of 4-20 mADC.
Definition
 32 degrees F, 77 degrees F, 122 degrees F, 167 degrees F, 212 degrees F.
Term
 What is the gain for a transmitter with an input span of 20 inches of water column and an output signal of 4-20 mADC?
Definition
Term
 What calibration error is present when a device records a consistent error or 0.2 mADC at each of the five test points?
Definition
 Zero shift
Term
 When the as-found calibration shows that the output varies depending on the direction of test points (upscale or downscale), the instrument has this type of error.
Definition
 Hysteresis
Term
 What should the output signal be at 73 inches of water on an instrument with an input range of 0-250 inches of water and an output range of 4-20 mADC?
Definition
Term
 A smart instrument differs from a conventional instrument because of the pressure of this feature.
Definition
 Microprocessor
Term
 Describe the use of an instrument spec sheet.
Definition
Term
 Atmospheric pressure is defined as
Definition
 14.7 psia
Term
 Which type of pressure sensing element uses a one-piece metallic unit with deep folds to convert pressure changes to linear movement?
Definition
 Bellows
Term
 A pressure that is observed to change within a sealed, fixed volume vessel is likely indicative of a change in what to the vessel?
Definition
 Temperature
Term
 What is the name of a pressure-sensing device that begins to measure increasing pressure from 0 pounds per square inch absolute?
Definition
 Absolute pressure device
Term
 A pressure switch tagged PSL trips at what point?
Definition
 A decrease in pressure below the set point
Term
 What is that weight of 1 cubic foot of water at standard temperature pressure conditions?
Definition
 62.43 pounds
Term
 What type of pressure transducer generates a voltage as the pressure increases?
Definition
 Piezoelectric
Term
 If a pressure transmitter with an output of 4-20 milliamperes DC and calibration of 0-25 pounds per square inch gauge is transmitting a signal of 6 milliamperes DC with 0 pounds per square inch gauge present on the sensor, this could be a sign of what type of issue?
Definition
 Zero error
Term
 What is the unit of pressure measure in the SI system of measurements?
Definition
 The pascal
Term
 The relationship between pressure and temperature of a gas can be examined using which of the following?
Definition
 Ideal gas law
Term
 A level measurement device monitoring the level of glycol in a process tank reports a level of 37%. After some time, the level measurement device reports a level of 42%. What type of instrument is the level measurement device?
Definition
 Continuous
Term
 A cylindrical process vessel has a diameter of 13.5 feet and a height of 50 feet. What is the volume of the vessel?
Definition
 7,153 cubic feetV=(3.14)(R^2)(H)
Term
 How many gallons would be contained in a process vessel with an internal volume of 1,293 cubic feet?
Definition
 9,672 gallonsGallons=CuFt X 7.48
Term
 What is the density of an object with a mass of 361 pounds that occupies a volume of 100 cubic inches?
Definition
 3.61 pounds per cubic inchD=M/V
Term
 What is the specific gravity of a liquid that weighs 156.49 pounds per cubic foot?
Definition
 2.51SW=D/62.4
Term
 A tank contains 304.7 inches of water. What is the pressure at the bottom of the tank?
Definition
 11 psigPSI=H(in) X 0.0361
Term
 A column of mineral oil with a specific gravity of 0.905 generates a hyrdostatic head of 7 psi. How high is the column of mineral oil?
Definition
 214 inchesD=(SW)(0.0361), H=P/D
Term
 What is the specific volume of a gas with a density of 0.00356 pounds per cubic foot?
Definition
 280.9 pounds per cubic footSV=1/D
Term
 True or False. The pressure drop across a restriction is equal to the velocity.
Definition
 False
Term
 What type of flow is characterized as a straight-line flow of a fluid?
Definition
 Laminar
Term
 In which type of flow meter does all of the fluid pass through the meter in nearly isolated quantities?
Definition
 Displacement
Term
 True or False. RN is a unitless number that is used to determine the resistance to fluid flow in a process line.
Definition
 True
Term
 Which of the following instruments operates on the principle of oscillating tube frequency driven by an electromagnetic drive coil?
Definition
 Coriolis meter
Term
 True or False. Because steam is considered a gas, pressure and temperature changes affect its density.
Definition
 True
Term
 Define vena contracta.
Definition
 The point downstream of a line restriction where fluid velocity is highest.
Term
 What happens when velocity is increased in a flow line?
Definition
 Pressure decreases
Term
 True or False. An orifice plate is commonly installed so that the beveled edge faces upstream.
Definition
 False
Term
 Temperature is the measure of the _ of molecules in a substance.
Definition
 Kinetic energy
Term
 This temperature scale is based on the freezing point of water at 0 degrees and the boiling point at 100 degrees.
Definition
 Celsius
Term
 Convert 762 degrees R to Fahrenheit.
Definition
 302.33 degrees
Term
 The _ temperature element works on the principle of two metals that expand at different rates when heated.
Definition
 Bimetallic
Term
 Temperature switches uses this type of signal to control a process.
Definition
 Discrete
Term
 A _ element works on the principle of two dissimilar metals that generate a small voltage as a function of temperature difference.
Definition
 Thermocouple
Term
 What is the color of the negative lead of an ANSI-compliant type J thermocouple?
Definition
 Red
Term
 The _ temperature sensor measures temperature based of changes in resistance and is commonly constructed of a fine platinum wire because of the inherent linearity?
Definition
 RTD
Term
 The most sensitive temperature sensor is the _?
Definition
 Thermistor
Term
 A temperature transmitter ranges from 25 degrees F to 1,190 degrees F. The output of the transmitter is measured at 14.96 milliamperes direct current. What is the process temperature?
Definition
 823 degrees
Term
 A temperature transmitter ranges from 0 degrees C to 100 degrees C. The process temperature is 23.8 degrees C. What should the transmitter output read?
Definition
Term
 A smart device operates based on a _?
Definition
 Microprocessor
Term
 When does a smart communicator require calibration?
Definition
 Never
Term
 The HART protocol operates using the _ method.
Definition
 Frequency shift keying
Term
 What is the minimum loop resistance for communication with a HART device?
Definition
 250 Ohms
Term
 Which section of a HART device converts an analog value to a digital value?
Definition
Term
 What is the purpose of switches on a HART device?
Definition
 Set security and alarm settings.
Term
 A pressure transmitter under test has 235 inches of water applied by a traceable pressure standard. The HART communicator indicates a pressure of 243 inches of water. What should the technician do?
Definition
 Trim the sensor input of the transmitter.
Term
 A temperature transmitter under test has an output of 4-20 milliamperes DC. A traceable digital multimeter is connected and reads 7.42 milliamperes DC. The HART communicator indicates a value of 7.21 milliamperes DC. What should the technician do in this situation?
Definition
 Trim the AO of the transmitter.
Term
 When sending changes to a HART transmitter with a communicator in an active process, what should the technician do to ensure the process is not affected?
Definition
 Put the control loop in manual mode.
Term
 Which type of valve requires linear movement to change valve position?
Definition
 Sliding stem
Term
 A valve _ is a flexible membrane considered to be a sensing element.
Definition
 Diaphragm
Term
 Force is equal to _ times _.
Definition
 Pressure times area
Term
 _ material is used to prevent leakage at the valve stem.
Definition
 Packing
Term
 A valve actuator that responds to increasing pressure by extending the attached stem is a _.
Definition
 Direct-acting actuator
Term
 The internal component of a globe valve that comes into direct contact with the process fluid is called the _.
Definition
 Trim
Term
 A _ valve is often used for large pipe diameters.
Definition
 Butterfly
Term
 A pneumatic actuator is typically supplied with pressure in the range of _ pounds per square inch.
Definition
 3-15 pounds per square inch
Term
 The process of verifying that the valve actuator can travel in a full range is called _.
Definition
 Bench set
Term
 A _ actuator has a cylinder and piston assembly.
Definition
 Hydraulic
Term
 The _ of a valve actuator is critical to ensure the process safety in the event of pneumatic pressure or electrical power loss.
Definition
 Fail safe
Term
 Which type of mechanism can convert linear motion to rotary motion?
Definition
 Rack and pinion
Term
 A _ converts electrical energy into linear motion.
Definition
 Solenoid
Term
 A linear variable differential transformer is used for _.
Definition
 Determining valve stem position
Term
 A valve positioner is used to _ for final control elements.
Definition
 Increase accuracy
Term
 An electropneumatic positioner uses an _ that allows the positioner to receive a current signal.
Definition
 I/P Transducer
Term
 Which component of a microprocessor-based control system performs the calculation?
Definition
 Controller
Term
 When dealing with an automatic control system, the operator...
Definition
 observes the process and data provided by the system and makes minute adjustments if needed when an issue arises.
Term
 A type of controller commonly used for boiler burner control is the...
Definition
 single loop controller
Term
 What common PLC programming language resembles a motor control diagram?
Definition
Term
 Once a PLC program is written using one of the programming languages, it is...
Definition
 checked for conflicts and compiled into machine language by the software.
Term
 What does the acronym ESD stand for in terms of a process control system's safety design?
Definition
 Emergency shut down
Term
 Safety relays and PLCs are typically identified by which color?
Definition
 Red
Term
 Solid state switching devices are indicated by a _ around the contact.
Definition
 Diamond
Term
 Which type of control card turns positive voltage on and off to a device?
Definition
 Sourcing output
Term
 What is the specific set of rules used by a process controller to solve a problem?
Definition
 Algorithm
Term
 A steam heat exchanger has a flow rate of 20 gallons per minute and a volume of 1 gallon per minute. The process fluid leaving the heat exchanger exhibits unstable temperature fluctuations around the set point. What is the likely cause of this instability?
Definition
 The process has a small capacity for energy storage.
Term
 An instrument technician is installing the control system for an industrial parts washer. The pasts washer contains a cleaning solvent that is supplied to spray nozzles by a pump. The operator sets the parts washer to run for 30, 60, or 90 minutes depending on how many parts are put into the washer. What type of control is used by this machine?
Definition
 Open-loop control
Term
 An injection molding machine is used in a plant to manufacture car door panels. A conveyor assembly moves bulk plastic beads to a hopper, which is equipped with an optical level sensor. When the hopper is at the correct level, the conveyor stops feeding plastic beads. When the level drops below the level sensors, the conveyor starts feeding plastic beads into the hopper. What type of control is used by the machine?
Definition
 Closed-loop control
Term
 A water pump is installed to maintain water systems pressure. A pressure switch is installed to control the pump. The switch turns the pump on when the pressure reaches 30 pounds per square inch and turns the pump off when the pressure reaches 50 pounds per square inch. What is the switch doing to control the pump?
Definition
 The switch uses a dead band of 20 pounds per square inch to prevent the pump from cycling excessively.
Term
 A PID controller has four adjustments on the user interface: gain, reset, rate, and damping. Which adjustment would be used to increase the proportional action?
Definition
 Gain
Term
 A process operator recently changed the settings on a PID controller. The digital chart recorder now shows a consistent offset between the set point and the process variable. What is the likely cause of this offset?
Definition
 The operator turned the reset off.
Term
 A process vessel with a large capacity exhibits a large overshoot of temperature during a 12-hour process. What setting in the PID controller could help reduce such an overshoot?
Definition
 Rate
Term
 A control system uses two process controllers that interact to achieve a control function. What type of control action is used in this process?
Definition
Term
 When installing a differential pressure transmitter for liquid service, the transmitter should be placed...
Definition
 below the process taps
Term
 Tubing that is installed to carry process medium to the transmitter is known as _ tubing.
Definition
 impulse
Term
 The proper setting for a digital multimeter when measuring loop current at the instrument test terminal is...
Definition
 current
Term
 Shielded instrumentation cable is typically connected to earth ground _, unless specific requirements are identified in the project or plan standards.
Definition
 only at the controller
Term
 An _ is a piping accessory which uses a thin flexible barrier, often a metal alloy, to isolate an instrument from the effects of a process.
Definition
 isolation diaphragm
Term
 Proper use of instrument manifolds requires...
Definition
 following facility specific procedures as well as manufacturers' guidelines.
Term
 The rating at which a device can briefly withstand pressure before the device separates, a component leaks, or both is known as...
Definition
 burst
Term
 Intrinsic barriers are used to...
Definition
 control fault currents.
Term
 At what point in a project can loop checking begin?
Definition
 Only after all loop components are permanently installed.
Term
 What radio communication standard is commonly used to prevent mistakes in alphabetical characters?
Definition
 NATO alphabet
Term
 How can a technician ensure they are using the most current documentation?
Definition
 Verify the document revision is the most current available in the project library system.
Term
 What ensures the loop checking procedure is consistently performed by different teams of instrument technicians?
Definition
 Using a standardized loop checking sheet with written procedures.
Term
 What document would the technician use to note that a valve is installed backward with regards to flow?
Definition
 P&ID
Term
 Which of the following are the two main methods for measurement signal loop checking?
Definition
 Forcing and simulation
Term
 Assume a technician uses a HART communicator to loop test a HART-capable device with a ranch of 32-212 degrees F. What reading should the control room operator read if the technician simulates a 16 milliampere DC valvue?
Definition
 167 degrees F
Term
 What setting on a loop calibrator would be used to produce a 12 milliampere DC signal on an instrument loop that is powered from an external power supply?
Definition
 Two-wire transmitter simulation
Term
 What is the first action an instrument technician should perform if the instrument power supply immediately blows a fuse upon energization?
Definition
 Perform a continuity check to identify a short circuit on ground fault.
Term
 What is a preplanned and documented process of completing the start-up procedure.
Definition
 Commissioning
Term
 What is the process of visually inspecting the equipment and piping to ensure it conforms to the P&ID and project specifications?
Definition
 P&ID walkdown
Term
 Which inert gas is used to purge process pipes and vessels?
Definition
 Nitrogen
Term
 How can a technician reverse the rotational direction of a three-phase induction motor?
Definition
Term
 If a technician notices a hissing sound coming from outside a vessel containing ammonia, what is the best plan of action?
Definition
 Check the wind sock direction and relocate upwind immediately.
Term
 What procedure is used to optimize the controller settings and prevent unwanted oscillations in the process variable?
Definition
 Loop tuning
Term
 What term describes the point at which the process variable exhibits sustained oscillations with equal amplitude?
Definition
 Ultimate gain
Term
 A technician observes a PID loop's ultimate gain to be 5. What is the predicted best gain setting based on the Ziegler-Nichols method?
Definition
 3
Term
 A technician observes a PID loop's ultimate period to be 800 seconds. What is the predicted best integral setting based on the Ziegler-Nichols method?
Definition
 400 seconds.
Term
 A technician properly implements the Ziegler-Nichols tuning procedure. However, the process variable still exhibits excessive error. What is the likely cause?
Definition
 The Ziegler-Nichols method may not be appropriate for this control loop.
Term
 What step should the technician take if the initial proposed solution to fix a motor starter problem does not fix the problem?
Definition
Term
 What method is helpful when looking for ground faults on signal wiring?
Definition
 Divide and conquer
Term
 Which factor could lead to consistently high output from a HART transmitter?
Definition
 Media specific gravity has increased
Term
 Which of the following provides a method to measure a 4-20 milliampere DC loop current without breaking the loop?
Definition
 Test terminal diode
Term
 What does a DCS I/O module use to convert an analog signal to a digital signal?
Definition
Term
 What is a DCS?
Definition
 A network of components connected to a plant data highway
Term
 Which of the following is not a common topology for a DCS?
Definition
 Zigzag
Term
 What DCS component allows interconnection by performing a translation?
Definition
 Gateway
Term
 How can a technician prevent ground loops?
Definition
 Terminate the cable shield at one end only, typically at the controller end.
Term
 What is the name of a device that uses light to eliminate ground loops in a signal cables?
Definition
 Opto-isolator
Term
 What is the best method to avoid inductive coupling in signal cables that cross power conductors?
Definition
 Cross power conductors at 90 degrees perpendicular.
Term
 True or False. A typical DCS can handle up to 50 I/O points.
Definition
 False
Term
 Which DCS physical layer for communication uses light to transmit data?
Definition
 Fiber optic
Term
 What is the role of ANSI in the development of design standards?
Definition
 Serve as a neutral third party to coordinate the development of standards
Term
 What document could be used as a reference if no design standard exists?
Definition
 RP
Term
 Which organization publishes P&ID design standards?
Definition
 ANSI/ISA, JIS, PIP
Term
 What is the purpose of the ISO 9000 standardization?
Definition
 To provide a framework for maintaining quality within a manufacturer's plant
Term
 The acronym PDCA stands for...
Definition
 Plan, do, check, act
Term
 A document that breaks a project into a series of deliverables is called a...
Definition
 WBS (Work breakdown structure)
Term
 Before an instrument technician deviates from the project documents, a _ form must be submitted.
Definition
 MOC (management of change)
Term
 During the closing phase of a project, a UAT is completed. What is its purpose?
Definition
 Prove the equipment operates to the design specifications
Term
 Where should project documentations be stored?
Definition
 Project library
Term
 What is the buoyant force extended on a displacer with a volume of 200 cubic inches fully submerged in a tank filled with water (a specific gravity of 1.00)?
Definition
 7.22 lbsS=(H)(0.0361)
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