問題一覧
1
For a 180- degree tubing bend the zero on the forming wheel of the bender must be aligned with what number on the slide block at the beginning of the bend
180
2
The most frequent control mode is
Automatic
3
Oil based pipe joint compound should never be used on threads of pipe used to Coney oxygen because
in contact could explode
4
A 4 wire 100 ohm PT RTD is being checked at 32 F what resistance should be expected between the red and white wire
100 ohms
5
The set point on a controller is a specific valve at which
A process variable is to be maintained
6
The nominal size of tubing is determined by its
OD
7
Valves are used to control all of the following except
flow of impurities
8
Pressure is expressed mathematically as
P = F /A
9
In a non linear power supply the dc output voltage is regulated by
SCR
10
old packing should be replaced with a new packing which is
in kind
11
The accuracy of a type J T/C is being questioned what setting on a multimeter will best troubleshoot the issue
Millivolts
12
A reverse acting positioner
closes a control valve as the signal decreases
13
substance that is capable of reducing friction heat and wear when applied as a film between two surfaces is
Lubricant
14
What does the reset control mode eliminate
circuit overload
15
convert 87.6 Celsius to Fahrenheit
189.58
16
In reference to PID controllers reset relates to:
the integral of change in the error signal
17
One PSI is equal to how many inches of water
27.73
18
During pneumatic testing what is used to identify the pressure leak
Soapy water
19
What causes the valve stem solenoid vale to move up or down?
Magnetic field induced by an electrical coil that surrounds the stem
20
The most common standard set symbols for instrumentation is from
ISA
21
Connecting tubing into a junction box requires
Bulkhead fittings
22
The final step in commissioning should be
Recording the documents
23
Pressure switches are actuated by
Bellow diaphragms or bourdon tubes
24
Measurements are always taken from the tubing centerline except for the
first bend
25
Loop testing involves simulation of the:
Zero and span
26
What device is used to measure flow?
Venturi Tube
27
An RTD is used to measure
Temperature
28
What does a pneumatic valve positioner do
controls the operation of a valve actuator
29
RTD elements are normally constructed of
Platinum copper or nickel
30
When selecting a regulator, choose the:
Overpressure protection that protects the regulator
31
troubleshooting starts with
verifying that a problem exists
32
For a 45 degree tubing bend the bend mark must be aligned with what mark on the slide block at the beginning of the bend
O
33
Thread compound which is normally applied using a brush is called
Pipe dope
34
When inspecting a regulator controlled nitrogen pad system on a large storage tank and no pressure is found what critical item besides the regulator should be checked
Supply pressure
35
Water in an air system causes all of the following except
Pressure fluctuations in process
36
The range of the transmitter is the
Difference between upper and lower limits
37
27.7 inches of H20 is equivalent to
1 psi
38
When deburring tubing which of the following should be avoided
Tapering the internal diameter
39
nuclear level detectors are used when
traditional level sensors present a risk to life or the environment
40
The process parameter that is selected for control is the
Controlled variable
41
A disadvantage of direct operated regulators is
their poor sensitivity
42
The primary goal for any closed loop control system is
Stability
43
Gaskets are usually specified for particular range of
Temperature and pressure
44
What information does a P&ID provide
Shows instrument locations as it relates to the process
45
What can happen if an instrument is getting too much EMI noise
It can lead to instrument inaccuracy
46
When replacing a control valve in kind what is least important
Location of signal ports
47
Smart instrument transmission required which of the following for calibration and configuration
Communicator
48
In proving and calibrating a loop, equipment is required to:
Receive an output signals
49
Where should a dp flow transmitter high pressure side be connected to the orphis taps
upstream
50
A worker knows the tag number of an instrument and needs to identify the drawing and documents relating to the particular instrument which of the following would be the best place to find the information
Instrument index
51
Convert 72 degrees F to Celsius
22.2 C
52
What is the major cause of death from electrical shock
Heart fibrillation
53
How many ¾” valves are on the figure provided?
4
54
Which wire brush is the best brush for stainless steel materials
Stainless steel
55
What does a venturi Tube measure
Process flow
56
Proving a loop is a
point to point interconnection
57
A technician is using an instrument tag number to withdraw an instrument from stores the technician is not sure if the hardware being pulled which document should the technician reference to ensure that the correct is withdrawn
instrumentation data sheet and PO
58
Which of the following is a basic principle of alternating current flowing in a conductor
The current flow is in one direction
59
If the proportional band of a controller is adjusted to the minimum position valve the controller action is likely to be
On/off
60
Where can the degree of slope on a tubing run be found
Installation drawings
61
when using soft rolled tubing it must be unrolled and straightened
By hand
62
the term “fail open” and “fail closed” are used to describe what valve component
Spring
63
In a cascade control loop what does a primary control loop determine for the secondary control loop
Setpoint
64
When properly calibrated and installed the most accurate primary flow element is the
Venturi tube
65
An orifice plate causes a pressure drop which can be measured to calculate
Flow
66
Where should a DP flow transmitters high pressure side be connected to the orifice tape
Upstream
67
Cleaning of piping and tubing is generally required after all of the following EXCEPT
Modification
68
Which of the following is not the type of lead line materials used on tubing and transmitters
copper tubing
69
When an I to P transducer is used on a pneumatic control valve that is set up to fail closed a signal input of 4mA from the control room will
Result in an air pressure of 3 psi which will close the control valve
70
What type of input signal does a valve actuator receive from a 4 to 20ma transducer
Pneumatic
71
PTFE tape used as a sealant should be wrapped
In the same direction as the threads
72
When commissioning a loop
Both the physical installation and system functions are checked
73
When simulating a turbine sensing element during calibration of a flowmeter the instrument technician might use
A pulse source and milliamp meter
74
A displacer level instrument is withdrawn from stores and handed over to pipefitters for installation. After it is installed, the technician goes to perform the instrument checkout. The technician is not able to get the displacer to respond. What troubleshooting step should be performed first?
Check and see if the mechanical stops installed for shipping were removed
75
Electronic instrument signal leads can be influenced by
Noise
76
Multiple instruments within a loop share a common
Loop number
77
Thread compound which is normally applied using a brush is called:
Pipe dope
78
The simplest liquid level measurement device is a
Float
79
A transmitter is not working correctly with a multimeter you check across the positive and negative terminals what is the next step
get in series with the loop
80
What valve or pump packing material that is used where caustics, mild acids, gases, and chemicals are present?
PTFE/Synthetic fiber
81
The final step in commissioning is
Verifying correct operation of safety devices
82
An analog instrument has been determined to have excessive noise on th signal in troubleshooting the problem what would a technician look for
The insulation is damaged on the signal wires
83
What is a diode
electronic device that allows current to flow in only One Direction
84
Any person working near equipment during lockout tagout conditions is considered an
Affected employee
85
A particulate filter is working properly, but light oil/water residue is showing up in the air. What should be done to correct this problem?
Add a coalescing filter
86
a controller automatic control describes
the final control element responding to an error signal or change in process
87
What will happen in a series circuit with four lights if anyone burns out
all the lights will be out
88
When receiving instruments for the first time you should
Inspect instrument for damage
89
What is indicated by a double solid line drawn though the instrument symbol?
The instrument is mounted in an auxiliary location
90
Most smart transmitters
use HART protocol communication
91
for most tube Bender radius blocks a 90 degree bend gains approximately
1 1/2 tube diameter
92
What does a P&ID provide
The instruments location as they relate to the process
93
fluid is flowing through the hole in end orifice plate what does the restricted fluid movement caused by size of the
the difference in pressure
94
the following are proper and safe methods for storing tubing except
tubing should be left uncovered
95
Which of the following should not be considered when cleaning instruments
cleaning frequency
96
Which of these values is measured in a circuit de-energized
Resistance
97
A decreasing output with increasing input describes:
Reverse action
98
Shielding of signal cable is an effective method to
Minimize EMI
99
What is the major cause of death from electrical shock
heart fibrillation
100
Tube gain is due to the fact that
tubing changes ID when bending occurs