Linearity Error
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Федерация 中国 (China) 日本 (Japan) 대한민국 (Korea) 台灣 (Taiwan) See All Countries Toggle navigation INNOVATIONER BUTIK SUPPORT ANVÄNDARGRUPPER Sverige Sensor Terminology Publish Date: sep 23, 2013 | 5 Ratings | 4,60 out of 5 | linearity error calculation Print Overview This tutorial is part of the National Instruments Measurement Fundamentals series. sensor linearity definition Each tutorial in this series, will teach you a specific topic of common measurement applications, by explaining the theory linearity error definition and giving practical examples. This tutorial will cover sensors and the terminology associated with them. For the complete list of tutorials, return to the NI Measurement Fundamentals Main page. Table of Contents sensitivity error Sensitivity Range Precision Resolution Accuracy Offset Linearity Hysteresis Response Time Dynamic Linearity 1. Sensitivity The sensitivity of the sensor is defined as the slope of the output characteristic curve (DY/DX in Figure 1) or, more generally, the minimum input of physical parameter that will create a detectable output change. In some sensors, the sensitivity is defined as the input parameter change required to
Nonlinearity Error Definition
produce a standardized output change. In others, it is defined as an output voltage change for a given change in input parameter. For example, a typical blood pressure transducer may have a sensitivity rating of 10 mV/V/mm Hg; that is, there will be a 10-mV output voltage for each volt of excitation potential and each mm Hg of applied pressure. Sensitivity Error The sensitivity error (shown as a dotted curve in Figure 1) is a departure from the ideal slope of the characteristic curve. For example, the pressure transducer discussed above may have an actual sensitivity of 7.8 mV/V/mm Hg instead of 10 mV/V/mm Hg. Back to Top 2. Range The range of the sensor is the maximum and minimum values of applied parameter that can be measured. For example, a given pressure sensor may have a range of -400 to +400 mm Hg. Alternatively, the positive and negative ranges often are unequal. For example, a certain medical blood pressure transducer is specified to have a minimum (vacuum) limit of -50 mm Hg (Ymin in Figure 1) and a maximum (pressure) limit of +450 mm Hg (Ymax in Fig
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Linearity Error Excel
for Motorsport Digiforce Services About Us Blog Resources Free Engineering Unit Conversion Program Glossary of how to calculate linearity error in excel Transducer-Related Terms Instrument Calibration & Test Procedure Videos ATEX, Intrinsic Safety & Hazardous Area Information IP Ratings and Equivalent NEMA Ratings linearity error meaning Reference Articles on Sensors and Transducers Engineering Notes on Pressure Measurement Links to Other Useful Websites Distributors Contact Us Quick Enquiry Form Name: Email Address or Phone No: Your Enquiry: >>You Are Here: Home > Technical http://www.ni.com/white-paper/14860/en/ Resources > Technical Notes on Pressure Sensing Linearity or nonlinearity? Linearity error is the deviation of the sensor output curve from a specified straight line over a desired pressure range. The linearity error value is normally specified as a percentage of the specified pressure range. If a sensor is only used over half the specified range and you are able to set the maximum value to be used then the linearity http://www.appmeas.co.uk/technical-notes/linearity-or-nonlinearity.html error is calculated from this value, which of course is going to provide improved accuracy over that specified by the manufacturer. There are two common ways of specifying the linearity error: BFSL BFSL stands for best fit straight line. The error is specified as the maximum deviation +/-x% of span of output value from the straight line. TBL TBL stands for terminal base linearity or end-point linearity. TBL is determined by drawing a straight line (L1) between the end data points on the output curve. The data point is chosen to achieve the maximum length of the perpendicular line. As the shape of the output curve is repeatable, it is possible to linearise the output using external electronics, such as compensation circuits or a microprocessor. Normally the linearity error is the least significant of all the errors in any given pressure sensor: commonly in the region of 0.1 to 0.2 or better. This very much depends on the material used for the diaphragm, as some materials, such as stainless steel and aluminium alloys have very linear sections, whereas others such as high carbon steels are very curved. In such cases it is difficult to determine the elastic area of the diaphragm material to achieve long life together with accurate linearity. Read more: Index
to Thread Search Forums Recent Posts Today's Posts 1Next > Nov 11, 2009 #1 mafrasm Thread Starter New Member Nov 11, 2009 6 0 considering below figure (attachment) http://forum.allaboutcircuits.com/threads/what-does-it-mean-by-linearity-error-maximum-linearity-error-percentage.30052/ plz can any body tell me how to derive equation relating Vo,X (i http://www.zweigmedia.com/RealWorld/calctopic1/linearapprox.html think it can be done using mesh equations..but im not sure with it..) and derive the relation for linearity error and the maximum linearity error percentage...advance thanks......... Attached Files: Doc1.doc File size: 24.5 KB Views: 31 #1 Like Reply Nov 11, 2009 #2 mafrasm Thread Starter New Member Nov 11, 2009 6 linearity error 0 plz can any body help me regarding above post..... #2 Like Reply Nov 11, 2009 #3 t_n_k AAC Fanatic! Mar 6, 2009 5,448 782 If X is a distance measurement you can't solve the problem as you have presented it. Suppose the total resistance along the potentiometer body is Rp - which is the missing information. The positional resistance is then So the voltage measured linearity error definition at X would be where If the meter resistance were infinite than you would have an ideal case in which So the non-linearity you seek to quantify is the deviation from the actual value of Vx measured, taking account of the meter loading due to finite meter resistance (Rm), versus the ideal value of Vx measured with infinite meter resistance. #3 Like Reply Nov 12, 2009 #4 mafrasm Thread Starter New Member Nov 11, 2009 6 0 thank you very much! actually earlier i was wondering, what does it mean by linearity error? and now i understood its , simply "the error caused due to the presence of the measuring instrument in the system and the deviation of its properties from ideal case of the measuring instrument." or (error caused due to presence of non ideal measuring instrument in the cicuit) ie: in this case the error of the reading "resistance Rx",due to the presence of "voltmeter resistance Rm" in parallel with Rx... #4 Like Reply Show Ignored Content 1Next > Loading... Related Forum Posts: What does it truly mean of 40mA draw Posted by Eric So in forum: General Electronics Chat Replies: 5 Views: 15
Finite Math Everything for Finite Math & Calculus Español Note To understand this topic, you will need to be familiar with derivatives, as discussed in Chapter 3 of Calculus Applied to the Real World. If you like, you can review the topic summary material on techniques of differentiation or, for a more detailed study, the on-line tutorials on derivatives of powers, sums, and constant multipes. We start with the observation that if you zoom in to a portion of a smooth curve near a specified point, it becomes indistinguishable from the tangent line at that point. In other words: The values of the function are close to the values of the linear function whose graph is the tangent line. For this reason, the linear function whose graph is the tangent line to $y = f(x)$ at a specified point $(a, f(a))$ is called the linear approximation of $f(x)$ near $x = a.$ Q What is the formula for the linear approximation? A All we need is the equation of the tangent line at a specified point $(a, f(a)).$ Since the tangent line at $(a, f(a))$ has slope $f'(a),$ we can write down its equation using the point-slope formula: $y= y_0 + m(x - x_0)$ $= f(a) + f'(a)(x - a)$ Thus, the the linear approximation to $f(x)$ near $x = a$ is given by $L(x) = f(a) + f'(a)(x - a).$ Q The above argument is based on geometry: the fact that the tangent line is close to the original graph near the point of tangency. Is there an algebriac way of seeing why this is true? A Yes. This links to an algebraic derivation of the linear approximation. Linear Approximation of $f(x)$ Near $x = a$ If $x$ is close to a, then $f(x) \approx f(a) + (x-a)f'(a).$ The right-hand side, $L(x) = f(a) + (x-a)f'(a),$ which is a linear function of $x,$ is called the linear approximation of $f(x)$ near $x = a.$ Example 1 Linear Approximation of the Square Root Let $f(x) = x^{1/2}.$ Find the linear approximation of $f$ near $x = 4$ (at the point $(4, f(4)) = (4, 2)$ on the graph), and use it to approximate $\sqrt{4.1.}$ Solution Since $f'(x) = 1/(2x^{1/2}),$ $f'(4) = 1/(2 \cdot 4^{1/2}) = 1/4.$ so the linear approx