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The density of a liquid affects the displacer's: length height buoyancy - ✔✔buoyancy What mode MUST the controller be in before any changes are made to the process variable? automatic manual shut-down power off - ✔✔manual Bills of material are found in: general arrangement drawings P&ID piping orthographics instrument detail drawings - ✔✔general arrangement drawings When bench calibrating a temperature RTD transmitter, the instrument technician should apply: hot air pressure cold air pressure resistance
voltage - ✔✔resistance Before working on a de-energized circuit containing a capacitor, what must be done? discharge the capacitor re-energize the circuit defibrillate the system remove the lockouts - ✔✔discharge the capacitor The MINIMUM value of the measured process range is considered to be: upper measured value 3 psi and 4 ma zero input value span value - ✔✔3 psi and 4 ma A solenoid valve is often used to regulate temperature direct airflow that opens or closes an air operated valve regulate the amp that is used to open/close control valve control the voltage that is used to open/close contacts - ✔✔direct airflow that opens or closes an air- operated valve Viscosity is analyzed in all of the following ways EXCEPT: the falling all method the viscositron method the rotating disc method
LED - ✔✔SSR
In modulating control, the first step is to compute the error between controlled variable and setpoint. The second step is to produce a(n): output signal modulating mode feedback set point process feedback - ✔✔output signal A dashpot timer relay: is well suited for fast on-off cycles is a type of pneumatic relay has NO moving parts requires a long reset time - ✔✔is a type of pneumatic relay A photosensor is a: double throw double pole switch silicone-controlled rectifier variable resistor transformer - ✔✔silicone-controlled rectifier MOST pneumatic receivers operate in the range of: 1 - 5 psi 0 - 10 psi 3 - 15 psi
0 - 100 psi - ✔✔ 3 - 15 psi Signal cable shields should be connected to ground at: 1 point in the signal path each accessible point in the signal path each end of the path each junction point in the signal path - ✔✔1 point in the signal path What BEST determines the required torque for bolt tensioning? load requirements washer type number of bolts used grade of bolt - ✔✔grade of bolt Old packing should be replaced with new packing which is: one size larger one size smaller in kind softer material - ✔✔in kind Atmosphere testing must be conducted before entry into a confined space to check for: humidity level heat level oxygen content
minimizing the air gap in the coil core - ✔✔increasing number of turns in a coil When selecting a regulator, choose the: Larger range spring if two springs have the desired pressure setting. Regulator body size that is larger than the pipe size. Overpressure protection that protects the regulator Largest port diameter that will handle flow. - ✔✔overpressure protection that protects the regulator A decreasing output with increasing input describes: direct action nozzle equilibrium reverse action feedback axis - ✔✔reverse action The basic element of the shift register is the: NOR gate NAND gate latching circuit flip-flop circuit - ✔✔flip-flop circuit The program that is permanently entered into a PLC processor is called: Software Hardware Firmware
Techware - ✔✔firmware Needle valves are used for: low flow, high pressure drop, precision flow control general process control use high flow, low pressure drop, primary flow control quick opening nonlinear flow - ✔✔low flow, high pressure drop, precision flow control In a properly grounded system: voltage can flow the right way excess voltage & current are rapidly directed to the earth resistance to ground is high grounding electrodes may be aluminum - ✔✔excess voltage & current are rapidly directed to the earth Pressure is expressed mathematically as: increases as controller signal increases decreases when controller signal increases increases on loss of controller signal remains constant on loss of control signal - ✔✔decreases when controller signal increases The pneumatic output of a 3-15 psi instrument is at 50%. The actual output in pressure is: 3 psi 6 psi 9 psi
on-delay off-delay - ✔✔on-delay Which of the following is used to calibrate a DP transmitter? Wheatstone bridge Reluctance coil Wally box Ohmeter - ✔✔wally box Troubleshooting flow charts are MOST effective when: problems are identified instruments are operational there is little information available identifying system components - ✔✔problems are identified What instrument drawing shows an actual representation of a process operating sequence? Orthographic drawing Location drawing Isometric drawing P&ID - ✔✔P&ID The binary system is a base: 2 system 8 system
12 system 16 system - ✔✔2 system A common unit for volume of a gas is: CF ACFD SCFM SCF - ✔✔SCFM Pressure switches are actuated by: high pressure adjustment screws bellows, diaphragms, or bourdon tubes low pressure dead band adjustments normally open or normally closed contacts - ✔✔bellows, diaphragms, or bourdon tubes The word "piezoelectric" refers to a certain class of crystals that produce an electric signal when they are mechanically: Heated Cooled Deformed Inducted - ✔✔deformed An orifice plate causes a pressure drop which can be measured to calculate: pressure flow
3.9 inches 39.3 inches 42.0 inches - ✔✔39.3 inches If the proportional band of a controller is adjusted to the MINIMUM possible value, the controller action is likely to be: on/off variable operation excellent inoperative - ✔✔excellent The operation modes of a loop controller are: input and output feed back and feed forward manual, automatic and cascade set point, output, and process variable - ✔✔manual, automatic and cascade The span of an instrument with a 24-36 psig input is: 3 psig 12 psig 15 psig 18 psig - ✔✔12 psig A chemical, classified as a base, harms a human body by causing all the following EXCEPT: severe respiratory burns
dissolved skin tissue irritation to nose and throat membranes calcification of the tongue - ✔✔calcification of the tongue All of the following valves are used to regulate flow, EXCEPT: plug butterfly needle gate - ✔✔gate Which of the following tools should be used to remove old packing from the packing gland? Screwdriver Pocket knife Packing extractor Needle nose - ✔✔packing extractor The device that is used to check the integrity of tubing is the: Wallace and Tieman calibrator bubbler HART communicator Fluke 725 - ✔✔wallace and tieman calibrator A controller receives an input signal from a: final element
loop suffix installation detail loop number - ✔✔loop number What is a thermowell? Temperature-measuring device Void space for dampening temperature fluctuations Top side of a temperature transmitter Protective device to house a thermocouple - ✔✔protective device to house a thermocouple What is the major cause of death from electrical shock? Burns Heart fibrillation Head trauma Arc flash - ✔✔heart fibrillation The hydrostatic pressure created in a 10 foot tank with 8 feet water level is: 3.4 psi 4.3 psi 8 psi 10 psi - ✔✔8 psi An example of a direct measurement indicator is a: pressure gauge
bulb thermometer sight glass flowmeter - ✔✔pressure guage To create a NOR gate, add an inverter to the output of: an AND gate an OR gate an amplifier a NAND gate - ✔✔an OR gate Cutting oils are classified as: light colored & transparent dark & transparent mineral & lard blends active & inactive - ✔✔active & inactive Which of the following must be determined before selecting a pressure-reducing regulator? Capacity required Spring load Weight load Required desiccant - ✔✔capacity required Gaskets are usually specified for particular ranges of: temperature and pressure
simulated test run point to point interconnection revising the loop documents as built - ✔✔simulated test run A transmitter has a range 0 - 304.7" wc. What is the range in PSI? 0 - 7 psi 0 - 9 psi 0 - 10.7 psi 0 - 11 psi - ✔✔ 0 - 11 psi Hazards from Aerosol cans include all of the following EXCEPT: implosion due to sudden gas release explosion caused by high temperatures explosion caused by punctured cans chemical burns - ✔✔implosion due to sudden gas release When tuning a controller, increasing gain: decreases sensitivity increases sensitivity decreases precision increases precision - ✔✔increases sensitivity Which of the following materials is selected when resistance to corrosion or high temperatures is required? High-carbon steel
Low-carbon steel Nickel Alloy Nonferrous alloy - ✔✔nickel alloy Loop testing involves simulation of the: component settings zero and span corrective measures process variable - ✔✔process variable Which of the following describes span? Zero offset The difference between 3 and 15 The midpoint between3 and 15 Range - ✔✔the difference between 3 and 15 When a pressure switch is used as a low limit, deadband refers to the: increase in PV required to clear the condition distance from zero at which the switch initially operates distance from zero at which the switch returns to shelf state decrease in PV required to clear the condition - ✔✔distance from zero at which the switch returns to shelf state A bubbler is used as feedback in what type of system? Vibration
