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Chapter 6
Analog Electrical Devices and Measurements
l
^
k
I
Conductor
Figure 6.1 Current-carrying conductor
Magnetic field B
in a magnetic eld.
6.2 ANALOG DEVICES: CURRENT MEASUREMENTS
Direct Current
One way to measu
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Chapter 5
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Uncertainty Analysis
B1 0:20 N
95%
B2 0:30 N
ASSUMPTIONS Manufacturer specications reliable at 95% probability
KNOWN
FIND B
95%
SOLUTION Lacking information as to the statistics used to specify the uncertai
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Page 171
5.5
Systematic and Random Errors
171
But let us think about this. The insidious aspect of systematic error has been revealed. Why
doubt a measurement indication and suspect a systematic error? The mean value of the data
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Chapter 5
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Uncertainty Analysis
This chapter approaches uncertainty analysis as an evolution of information from test design
through nal data analysis. While the structure of the analysis remains the same at each step
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Page 135
4.5
135
Chi-Squared Distribution
with degrees of freedom, n M N 1. The pooled standard deviation of the means of x is
dened by
hsx i
hsx i p
4:22
MN
When the number of measurements of x are not the same between replicatio
Applications
Most physical properties that are
continuous or regular in time or
space with variations due to
random error
Failure or durability projections;
events whose outcomes tend to be
skewed toward the extremity of
the distribution
Processes in whic
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Page 105
3.4
Transfer Functions
105
Imaginary
Im[G(i )]
M( )
( )
Re[G(i )]
Real
Figure 3.20 Complex plane approach to describing
frequency response.
system to the input signal. The second term describes its transient response. In
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Page 99
3.3
Special Cases of the General System Model
99
3
Td
0.013 S
Steady response
Output signal E(t) [V]
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2
1.9
Damped
oscillations
1
Settling
time
(10%)
90%
Rise
time
0.009
0
0.00 0.0038
0.01
0.02
Time, t (s)
0.03
0.04
0.05
F
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Chapter 7
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Sampling, Digital Devices, and Data Acquisition
various levels of gray shading. The grayscale images in Figures 7.30 and 7.31 are 8-bit digital images;
each pixel is assigned a number between 0 and 256, wit
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Page 225
6.4
Analog Devices: Resistance Measurements
225
temperature sensor has a resistance of 100 V at 0 C, determine the value of R2 that would balance
the bridge at 0 C.
KNOWN R1 100 V
R3 R4 500 V
FIND
R2 for null balance cond
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Chapter 10
Flow Measurements
Example 10.8
For the orice meter in Example 10.3 with b 0:5 and a pressure drop of 50 cm Hg, calculate the
permanent pressure loss due to the meter that must be overcome by a pump.
KNOWN
H
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Page 453
10.6
Insertion Volume Flow Meters
453
Turbine meters offer a low-pressure drop and very good accuracy. A typical instruments
systematic uncertainty in ow rate is $0.25% (95%) with a turndown of 20:1. The measurements are
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Chapter 9
Page 378
Pressure and Velocity Measurements
SOLUTION The absolute pressure is found directly from Equation 9.2. Using the pressure at
the free surface as the reference pressure and the datum line for h0, the absolute
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Chapter 9
Page 414
Pressure and Velocity Measurements
*
the correlation R12(Dx ), where
*
R12 Dx
Z Z
A
*
*
*
*
I 1 Dx I 2 x Dx dx
9:54
*
so identifying the common particle and allowing the estimate of the particle displacemen
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Chapter 8
Page 360
Temperature Measurements
for conduction errors. Conduction errors should be minimized through appropriate design and
installation of temperature probes. Usually, the physical situation is sufciently complex
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8.7
Physical Errors in Temperature Measurement
363
One shield with an emissivity of 1 provides for an improvement over the case of no shields, but a
better choice of the surface characteristics of the shield material can
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Chapter 8
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Temperature Measurements
Table 8.7 Reference Functions for Selected Letter Designated Thermocouples
The relationship between emf and temperature is provided in the form of a polynomial in temperature [10]
E
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Chapter 8
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Temperature Measurements
0 and 100 into equally spaced degree divisions. This places 50 C as shown in Figure 8.1. What
assumption is implicit in this method of interpolation? It is obvious that we do not ha
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Page 291
7.8
Analog Input-Output Communication
291
Analog
signal in
+
Channel 1
CH1
+ Hi
+
Signal conditioning
and A/D conversion
GRD
Floating
input
Through
+
Channel N
CH N
+ Hi
+
Output
GRD
Ground
Source
GRD
Shielded
cable
Conn
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Chapter 7
Page 276
Sampling, Digital Devices, and Data Acquisition
Example 7.4
Compute the relative effect of quantization error (eQ/Ei) in the quantization of a 100-mV and a 1-V
analog signal using an 8-bit and a 12-bit A/D
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Page 261
7.2
Sampling Concepts
261
understand how instruments interface with data-acquisition systems, and
perform basic image processing on digital images.
7.2 SAMPLING CONCEPTS
Consider an analog signal and its discrete time series r
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Page 237
6.7
Analog Signal Conditioning: Special-Purpose Circuits
237
R
Cr
q
Ct
Transducer
Cc
Rc
Connecting cable
Eo q/Cr
Charge amplifier
Figure 6.23 Charge amplier circuit shown connected to a transducer.
open-loop gain. Because
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Page 255
Problems
R1
R2
C1
255
C2
Figure 6.38 Bridge circuit for Problem 6.8.
6.8
6.9
6.10
6.11
6.12
A reactance bridge arrangement replaces the resistor in a Wheatstone bridge with a capacitor or
inductor. Such a reactance bridge
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Page 321
8.4
Electrical Resistance Thermometry
321
Suppose the coefcient of resistance for this RTD is 0.003925 C1. A temperature measurement
is made by placing the RTD in the measuring environment and balancing the bridge by adj