{"id":52,"date":"2018-11-28T06:01:19","date_gmt":"2018-11-28T06:01:19","guid":{"rendered":"http:\/\/msp04.epgpbooks.inflibnet.ac.in\/?post_type=chapter&p=52"},"modified":"2022-01-07T05:59:42","modified_gmt":"2022-01-07T05:59:42","slug":"recorders-and-recording-system-i","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/chapter\/recorders-and-recording-system-i\/","title":{"rendered":"Recorders and Recording System I"},"content":{"raw":"
\"epgp<\/a>\r\n<\/span><\/div>\r\n
\r\n\r\n\u00a0 \u00a0Learning Objectives<\/strong>\r\n\r\n \r\n\r\nIn this module we will study about electronic recording devices.\r\n
    \r\n \t
  1. In the introduction first we will briefly discuss about a data recording system and its types<\/li>\r\n \t
  2. Under Graphic recorder we will study about Strip Chart Recorder, Circular Chart recorders <\/span>and XY recorders<\/span><\/li>\r\n \t
  3. In the end, we will study about Oscillographic Recorders and its types Galvanometric recorder and CRT recorders<\/li>\r\n<\/ol>\r\n\u00a0 \u00a0 Introduction<\/strong>\r\n\r\n \r\n

    A Recorder or an electronic recording device is a measuring instrument which displays time-varying signal in a form that can be examined or re-examined, even long after the signal has ceased to exist. A recording system (i) helps to preserve the information that can be obtained at any instant from the indicating instruments and (ii) the information regarding waveforms and transient behavior or any phase relationships in different parts of a circuit.<\/p>\r\n \r\n

    Recording systems are of two types (i) Analog recorders and (ii) Digital recorders. Analog recorders can be further classified as (a) Graphic recorders (b) Oscillographic and Digital recorders.<\/p>\r\n \r\n\r\nGraphic Chart Recorders<\/strong>\r\n\r\n \r\n

    A Graphic recorder draws a graph that relates 2 or more variables to time or to each other.Let us first study graphic chart recorder, which are of 3 types (i) strip chart (ii) circular and (iii) XY.<\/p>\r\n \r\n

    Strip Chart Recorders<\/strong><\/p>\r\n \r\n

    Here one or more variables are recorded with respect to time, so they are also called x-t recorder. Various components that <\/span>constitutes a strip chart recorder are described below \u2013<\/span><\/p>\r\n\r\n<\/div>\r\n

    \r\n\r\n\"\"\r\n\r\n \r\n

    Figure 1<\/strong>. \u2013 Various components of Strip Chart Recorders<\/p>\r\n \r\n\r\nFirst\r\n

      \r\n \t
    1. Paper Drive System \u2013 It consist of long roll of graph paper, also called as chart that moves vertically. It is driven by synchronous motor with a speed selector switch. This help to control speed of the chart conveniently in fixed increments.<\/li>\r\n<\/ol>\r\nNext is\r\n
        \r\n \t
      1. Marking Mechanism \u2013 Earlier most of the strip chart recorder were fitted with inked-pen and paper type recording system, but with recent advances various other categories of marking mechanism have been developed for both laboratory and industrial applications.<\/li>\r\n<\/ol>\r\nVarious types of marking mechanism in use are described below-\r\n\r\n \r\n

        a. Pen and Ink - This is the most familiar type of marking mechanism and types of pen used in this system are the bucket pen, the V-pen, the fiber-tipped pen and the ballpoint pen. The tips should not have any burrs or sharp edges, so that they do not pick up paper or damage the chart roll. The advantage of this system is its simplicity and low operating cost. This recorder work well over wide range of recording speeds and there is little friction between the stylus tip and the paper. This system has few drawbacks, like there is a hazard of ink spillage or when pen is damaged there can be impairment in ink flow. Ink can dry\u00a0in the tube connecting the pen and reservoir; this can clog or ruin the entire pen assembly. Finally, pen friction can introduce errors during recording and it can be operated at <\/span>frequency of few Hz only.<\/span><\/p>\r\n \r\n

        b. Impact Printing \u2013 It is a variant of <\/span>ink paper system. Here a moving pointer is clamped in a position and a press bar above the pointer presses down onto a carbon ribbon located between the pointer and the paper chart. Carbon markings imprinted on the chart paper serve as a record. Large-format recorder with a 0.28 m wide strip <\/span>start use impact printing method to record data. At any time, around 20 variables such as pressure, temperature, etc. can be recorded simultaneously.<\/span><\/p>\r\n \r\n

        c. Thermal writing \u2013 this inkless techniques involves thermal writing elements that are actuated by electric currents and output is traced on a heat sensitive paper. This method is more reliable and produces higher contrast traces. More advanced systems employ papers with waxed surfaces and special pens to record frequency response up to 40 Hz.<\/span><\/p>\r\n \r\n

        d. Electric Writing \u2013 Here electric writing substrate is used which is made up of a dense, black substrate coated with aluminum. A tungsten wire stylus is kept in light contact with the aluminum surface. When <\/span>voltage is applied, aluminum is etched and a blackish substrate is exposed. A minimum of 35 V dc is applied at a frequency of 8 kHz to avoid possible grounding via <\/span>aluminum chart. It has a high range of marking speed, a low stylus friction <\/span>and a long stylus life. The only drawback of this system is the high cost of paper.<\/span><\/p>\r\n \r\n

        e. Light Beam Method \u2013 in this system galvanometer is fitted with a mirror, which is attached in the spindle of the measuring coil, and a beam of light reflected through it strikes a photosensitive paper. This method works well at higher frequencies and allows relatively higher chart speed without compromising the resolution. Its main disadvantage is <\/span>high cost of paper and requires <\/span>development of photographic paper before records can be observed. This method is not suited for real time monitoring, as photographic plates or paper require development before any observations can be made.<\/span><\/p>\r\n\r\n<\/div>\r\n\"\"\r\n

        \r\n

        Figure 2<\/strong>. Light beam method assembly<\/p>\r\n \r\n

        f. Electrostatic Writing \u2013 Stylus used in this system produces a high voltage discharge that leaves a permanent trace on electrosensitive paper. This system is made up of 3 elements, an imaging head, a toning head and a vacuum knife. The imaging head consists of a linear array of 1000 wire elements, with 4 spaced wires per mm spread over a total length of 0.25 m. There are 32 copper bars on each side of the array, called shoes. When paper moves over image head, a negative voltage is applied to the selected wire element and to the closest shoes a positive voltage is applied. This leaves a positive charge on the paper at the written points and then paper passes through the toner head over the negatively charged ink particles and particles adhere wherever paper has a positive charge. Paper then passes through the vacuum knife that removes the excess ink. When paper is exposed to air, coated particles bond permanently to the paper and the record paper emerges dry.<\/p>\r\n \r\n

        Circular Chart Recorders<\/strong><\/span><\/p>\r\n\r\n<\/div>\r\n

        \r\n

        \u00a0 These chart recorders were developed to take advantage and handiness of spring wound clock and synchronous motor movements that can drive the chart in a circular manner. A Circular Recorder is shown in Figure 3.<\/p>\r\n\"\"\r\n\r\n \r\n

        Figure 3<\/strong>. (a) Circular Chart Coordinates (b) Circular Chart Recorder \u2013 Pen is attached to the pivot that writes over the circular chart<\/p>\r\n \r\n

        In this recorder a circular chart with ruled concentric circles form its scales. Plus, there are printed arcs that extend from the center to the chart\u2019s edges. When the pen of the recorder moves, it writes the measurement as it swings along these arcs. The chart is clamped to its geometric center. It rotates at a uniform rate and the time lapse is indicated by the angular position between the arcs. Due to this reason arcs are also called time arcs<\/em>. The speed of rotation can be adjusted by using a synchronous motor with suitable gear assembly. The instantaneous value of the quantity under measurement is indicated by the radial position of the pen. The figure 3(b) illustrates the recording part.<\/p>\r\n \r\n

        Magnitude of number of variable can be recording on a single chart. This helps in analyzing relationship between various measurements and it also saves the panel mounting space. The maximum chart diameter is around 0.3 m and the resolution along the scales is usually non-uniform.<\/p>\r\n \r\n

        X-Y Recorders<\/strong><\/span><\/p>\r\n \r\n

        A X-Y chart recorder plot the relationship between the variables, like <\/span>y=f(x)<\/em> (<\/span>function of x), instead of plotting each variable separately as a function of time. These recorders can display 2 varying quantities on the X-Y axes as in Cartesian coordinates. Here one the variables <\/span>is applied to x-input and other to y-input, and the variations are plotted against one another. Its functioning resembles <\/span>to that of single pen recorder, <\/span>only difference being the chart, i.e. Y-axis moves in response to the changes in the variable instead at a uniform rate.<\/span><\/p>\r\n\r\n<\/div>\r\n

        \r\n\r\n\"\"\r\n\r\n \r\n

        Figure 4<\/strong>. X-Y chart recorder<\/p>\r\n \r\n

        It is important to note that chart position remains fixed during the measurement, its the pen that moves simultaneously in X & Y direction based on the electrical signal applied to its input terminal. These recorders do have time base and can be used to plot variation in one variable against time as well. The mechanism of movement of a pen in X & Y direction is based on closed loop servo-system as illustrated in figure 4. This mechanism is similar to the servo-mechanism used in self-balancing\u00a0potentiometer. The rotating servo motors move the marking pen with help of a string and pulley arrangement.<\/span><\/p>\r\n \r\n

        X-Y recorders are economical to operate as <\/span>low cost papers can be used for <\/span>chart but are more expensive to buy in comparison to strip chart recorders. They cannot be used for continuous measurements. They have sensitivity upto 10 V\/mm, slewing speed of 1.5 m\/s with a frequency of 6 Hz in both X-Y <\/span>direction and has an accuracy of \u00b1 0.2 % of the full scale. Paper size used in <\/span>these recorder is 280mm x 220 mm or 440mm x 220mm. Input impedance range is from 100 K\u03a9 to 50 M\u03a9. X-Y recorders are employed for plotting current vs voltage curves for diodes and transistors, plotting B-H curves of magnetic materials and plotting speed-time curves for electric motors, etc.<\/span><\/p>\r\n \r\n

        Oscillographic Recorders<\/strong><\/p>\r\n \r\n

        Primarily there are two kinds of Oscillographc recorders, Galvanometeric or CRT recorder. Although, pen recorders, x-y recorders, strip-chart recorders and all may be considered oscillographic recorders. The oscillogrpahic recorders have <\/span>bandwidth greater than 20 kHz<\/span>. .<\/p>\r\n \r\n

        Galvanometric Recorders<\/strong><\/span><\/p>\r\n \r\n

        They have <\/span>2D display and recording devices consist of a mirror galvanometer, light source and continuously rolling light sensitive recording surface. The basic operation is illustrated in figure-5. When galvanometer in under the influence of an external source, an electrical signal through the coil causes galvanometer to rotate accordingly. <\/span>Light beam from the light source gets reflected from the galvanometer mirror and falls on to the recording surface, which is in proportion to the amplitude and to the rate change of the input signal being recorded.<\/span><\/p>\r\n\r\n<\/div>\r\n\"\"\r\n

        \r\n

        Figure 5<\/strong>. Galvanometeric Chart Recorder<\/p>\r\n \r\n

        More than one galvanometer can be used for recording data. To avoid confusion between overlapped recordings, the traces are identified by printing series of number corresponding to the galvanometer position on the edge of the film. In this system, a transmitted light from the source is passes through a numbered film wheel on to a paper. Reference grid lines are recorded by passing a some of the light through a grid line aperture that allows a series of fine bars of light moving sequentially in the same direction as the record travels, and gets exposed on to the record simultaneously with the galvanometer traces.<\/p>\r\n \r\n\r\nCRT Recorders<\/strong><\/span>\r\n\r\n \r\n

        These are 4 dimensional display and recording devices. The two axes are conventional ones i.e. X-axis and Y-axis. The third axis is Z-axis that can be identified by spot identity on display media or recoding surface. Y\u2019(Y Prime)-axis is the fourth axis which is the movement of the recording medium. A block diagram of CRT is shown in figure 6.<\/p>\r\n \r\n

        As the name implies, here a cathode ray tube is used and its output light gets focused on the record either by an optical lens or by using a fiber optic face plate on the CRT and the record is kept in contact with the fiber optic.<\/p>\r\n\r\n<\/div>\r\n\"\"\r\n\r\n \r\n

        Figure 6<\/strong>. Block diagram for CRT Recorder<\/p>\r\n \r\n

        With CRT recorders data can be recorded 1000 time faster than the galvanometer recorder and because of the 4 axes they have the capability to record data continuously.<\/p>\r\n \r\n\r\nSummary<\/strong>\r\n\r\n \r\n\r\nIn this module we studied about electronic recording devices.\r\n

          \r\n \t
        1. In the introduction first we will briefly discussed about a data recording system and its types<\/li>\r\n \t
        2. Under Graphic recorder we studied about Strip Chart Recorder, Circular Chart recorders and XY recorders<\/li>\r\n \t
        3. In the end, we studied about Oscillographic Recorders and its types, Galvanometric recorder and CRT recorders<\/li>\r\n<\/ol>\r\n\r\n\r\n\r\n
          you can view video on Recorders and Recording System I<\/strong><\/td>\r\n\"\"<\/a><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n\u00a0 \u00a0\u00a0References :-<\/strong>\r\n
            \r\n \t
          1. Electrical and Electronic Measurements and Instrumentation, <\/span>Sawhney A. K.<\/em>, Dhanpat Rai & Sons, Reprint 1985<\/span><\/li>\r\n \t
          2. Measurements and Instrumentation, Bakshi U.A., Bakshi A.V.,<\/em> Technical Publications, 2009<\/li>\r\n \t
          3. Principles of instrumental analysis, Skoog, Douglas A., F. James Holler, and<\/em> Stanley R. Crouc,. <\/em>Cengage learning, Edition 2017<\/li>\r\n \t
          4. Instrumentation, measurement and analysis. Nakra, B.C. and Chaudhry, K.K.,<\/em> Tata McGraw-Hill Education, 2003.<\/li>\r\n \t
          5. Measurement and instrumentation: theory and application, Morris, A. S., &<\/em> Langari, R<\/em>. , Academic Press, 2012.<\/li>\r\n<\/ol>","rendered":"
            \"epgp<\/a>
            \n<\/span><\/div>\n
            \n

            \u00a0 \u00a0Learning Objectives<\/strong><\/p>\n

             <\/p>\n

            In this module we will study about electronic recording devices.<\/p>\n

              \n
            1. In the introduction first we will briefly discuss about a data recording system and its types<\/li>\n
            2. Under Graphic recorder we will study about Strip Chart Recorder, Circular Chart recorders <\/span>and XY recorders<\/span><\/li>\n
            3. In the end, we will study about Oscillographic Recorders and its types Galvanometric recorder and CRT recorders<\/li>\n<\/ol>\n

              \u00a0 \u00a0 Introduction<\/strong><\/p>\n

               <\/p>\n

              A Recorder or an electronic recording device is a measuring instrument which displays time-varying signal in a form that can be examined or re-examined, even long after the signal has ceased to exist. A recording system (i) helps to preserve the information that can be obtained at any instant from the indicating instruments and (ii) the information regarding waveforms and transient behavior or any phase relationships in different parts of a circuit.<\/p>\n

               <\/p>\n

              Recording systems are of two types (i) Analog recorders and (ii) Digital recorders. Analog recorders can be further classified as (a) Graphic recorders (b) Oscillographic and Digital recorders.<\/p>\n

               <\/p>\n

              Graphic Chart Recorders<\/strong><\/p>\n

               <\/p>\n

              A Graphic recorder draws a graph that relates 2 or more variables to time or to each other.Let us first study graphic chart recorder, which are of 3 types (i) strip chart (ii) circular and (iii) XY.<\/p>\n

               <\/p>\n

              Strip Chart Recorders<\/strong><\/p>\n

               <\/p>\n

              Here one or more variables are recorded with respect to time, so they are also called x-t recorder. Various components that <\/span>constitutes a strip chart recorder are described below \u2013<\/span><\/p>\n<\/div>\n

              \n

              \"\"<\/p>\n

               <\/p>\n

              Figure 1<\/strong>. \u2013 Various components of Strip Chart Recorders<\/p>\n

               <\/p>\n

              First<\/p>\n

                \n
              1. Paper Drive System \u2013 It consist of long roll of graph paper, also called as chart that moves vertically. It is driven by synchronous motor with a speed selector switch. This help to control speed of the chart conveniently in fixed increments.<\/li>\n<\/ol>\n

                Next is<\/p>\n

                  \n
                1. Marking Mechanism \u2013 Earlier most of the strip chart recorder were fitted with inked-pen and paper type recording system, but with recent advances various other categories of marking mechanism have been developed for both laboratory and industrial applications.<\/li>\n<\/ol>\n

                  Various types of marking mechanism in use are described below-<\/p>\n

                   <\/p>\n

                  a. Pen and Ink – This is the most familiar type of marking mechanism and types of pen used in this system are the bucket pen, the V-pen, the fiber-tipped pen and the ballpoint pen. The tips should not have any burrs or sharp edges, so that they do not pick up paper or damage the chart roll. The advantage of this system is its simplicity and low operating cost. This recorder work well over wide range of recording speeds and there is little friction between the stylus tip and the paper. This system has few drawbacks, like there is a hazard of ink spillage or when pen is damaged there can be impairment in ink flow. Ink can dry\u00a0in the tube connecting the pen and reservoir; this can clog or ruin the entire pen assembly. Finally, pen friction can introduce errors during recording and it can be operated at <\/span>frequency of few Hz only.<\/span><\/p>\n

                   <\/p>\n

                  b. Impact Printing \u2013 It is a variant of <\/span>ink paper system. Here a moving pointer is clamped in a position and a press bar above the pointer presses down onto a carbon ribbon located between the pointer and the paper chart. Carbon markings imprinted on the chart paper serve as a record. Large-format recorder with a 0.28 m wide strip <\/span>start use impact printing method to record data. At any time, around 20 variables such as pressure, temperature, etc. can be recorded simultaneously.<\/span><\/p>\n

                   <\/p>\n

                  c. Thermal writing \u2013 this inkless techniques involves thermal writing elements that are actuated by electric currents and output is traced on a heat sensitive paper. This method is more reliable and produces higher contrast traces. More advanced systems employ papers with waxed surfaces and special pens to record frequency response up to 40 Hz.<\/span><\/p>\n

                   <\/p>\n

                  d. Electric Writing \u2013 Here electric writing substrate is used which is made up of a dense, black substrate coated with aluminum. A tungsten wire stylus is kept in light contact with the aluminum surface. When <\/span>voltage is applied, aluminum is etched and a blackish substrate is exposed. A minimum of 35 V dc is applied at a frequency of 8 kHz to avoid possible grounding via <\/span>aluminum chart. It has a high range of marking speed, a low stylus friction <\/span>and a long stylus life. The only drawback of this system is the high cost of paper.<\/span><\/p>\n

                   <\/p>\n

                  e. Light Beam Method \u2013 in this system galvanometer is fitted with a mirror, which is attached in the spindle of the measuring coil, and a beam of light reflected through it strikes a photosensitive paper. This method works well at higher frequencies and allows relatively higher chart speed without compromising the resolution. Its main disadvantage is <\/span>high cost of paper and requires <\/span>development of photographic paper before records can be observed. This method is not suited for real time monitoring, as photographic plates or paper require development before any observations can be made.<\/span><\/p>\n<\/div>\n

                  \"\"<\/p>\n

                  \n

                  Figure 2<\/strong>. Light beam method assembly<\/p>\n

                   <\/p>\n

                  f. Electrostatic Writing \u2013 Stylus used in this system produces a high voltage discharge that leaves a permanent trace on electrosensitive paper. This system is made up of 3 elements, an imaging head, a toning head and a vacuum knife. The imaging head consists of a linear array of 1000 wire elements, with 4 spaced wires per mm spread over a total length of 0.25 m. There are 32 copper bars on each side of the array, called shoes. When paper moves over image head, a negative voltage is applied to the selected wire element and to the closest shoes a positive voltage is applied. This leaves a positive charge on the paper at the written points and then paper passes through the toner head over the negatively charged ink particles and particles adhere wherever paper has a positive charge. Paper then passes through the vacuum knife that removes the excess ink. When paper is exposed to air, coated particles bond permanently to the paper and the record paper emerges dry.<\/p>\n

                   <\/p>\n

                  Circular Chart Recorders<\/strong><\/span><\/p>\n<\/div>\n

                  \n

                  \u00a0 These chart recorders were developed to take advantage and handiness of spring wound clock and synchronous motor movements that can drive the chart in a circular manner. A Circular Recorder is shown in Figure 3.<\/p>\n

                  \"\"<\/p>\n

                   <\/p>\n

                  Figure 3<\/strong>. (a) Circular Chart Coordinates (b) Circular Chart Recorder \u2013 Pen is attached to the pivot that writes over the circular chart<\/p>\n

                   <\/p>\n

                  In this recorder a circular chart with ruled concentric circles form its scales. Plus, there are printed arcs that extend from the center to the chart\u2019s edges. When the pen of the recorder moves, it writes the measurement as it swings along these arcs. The chart is clamped to its geometric center. It rotates at a uniform rate and the time lapse is indicated by the angular position between the arcs. Due to this reason arcs are also called time arcs<\/em>. The speed of rotation can be adjusted by using a synchronous motor with suitable gear assembly. The instantaneous value of the quantity under measurement is indicated by the radial position of the pen. The figure 3(b) illustrates the recording part.<\/p>\n

                   <\/p>\n

                  Magnitude of number of variable can be recording on a single chart. This helps in analyzing relationship between various measurements and it also saves the panel mounting space. The maximum chart diameter is around 0.3 m and the resolution along the scales is usually non-uniform.<\/p>\n

                   <\/p>\n

                  X-Y Recorders<\/strong><\/span><\/p>\n

                   <\/p>\n

                  A X-Y chart recorder plot the relationship between the variables, like <\/span>y=f(x)<\/em> (<\/span>function of x), instead of plotting each variable separately as a function of time. These recorders can display 2 varying quantities on the X-Y axes as in Cartesian coordinates. Here one the variables <\/span>is applied to x-input and other to y-input, and the variations are plotted against one another. Its functioning resembles <\/span>to that of single pen recorder, <\/span>only difference being the chart, i.e. Y-axis moves in response to the changes in the variable instead at a uniform rate.<\/span><\/p>\n<\/div>\n

                  \n

                  \"\"<\/p>\n

                   <\/p>\n

                  Figure 4<\/strong>. X-Y chart recorder<\/p>\n

                   <\/p>\n

                  It is important to note that chart position remains fixed during the measurement, its the pen that moves simultaneously in X & Y direction based on the electrical signal applied to its input terminal. These recorders do have time base and can be used to plot variation in one variable against time as well. The mechanism of movement of a pen in X & Y direction is based on closed loop servo-system as illustrated in figure 4. This mechanism is similar to the servo-mechanism used in self-balancing\u00a0potentiometer. The rotating servo motors move the marking pen with help of a string and pulley arrangement.<\/span><\/p>\n

                   <\/p>\n

                  X-Y recorders are economical to operate as <\/span>low cost papers can be used for <\/span>chart but are more expensive to buy in comparison to strip chart recorders. They cannot be used for continuous measurements. They have sensitivity upto 10 V\/mm, slewing speed of 1.5 m\/s with a frequency of 6 Hz in both X-Y <\/span>direction and has an accuracy of \u00b1 0.2 % of the full scale. Paper size used in <\/span>these recorder is 280mm x 220 mm or 440mm x 220mm. Input impedance range is from 100 K\u03a9 to 50 M\u03a9. X-Y recorders are employed for plotting current vs voltage curves for diodes and transistors, plotting B-H curves of magnetic materials and plotting speed-time curves for electric motors, etc.<\/span><\/p>\n

                   <\/p>\n

                  Oscillographic Recorders<\/strong><\/p>\n

                   <\/p>\n

                  Primarily there are two kinds of Oscillographc recorders, Galvanometeric or CRT recorder. Although, pen recorders, x-y recorders, strip-chart recorders and all may be considered oscillographic recorders. The oscillogrpahic recorders have <\/span>bandwidth greater than 20 kHz<\/span>. .<\/p>\n

                   <\/p>\n

                  Galvanometric Recorders<\/strong><\/span><\/p>\n

                   <\/p>\n

                  They have <\/span>2D display and recording devices consist of a mirror galvanometer, light source and continuously rolling light sensitive recording surface. The basic operation is illustrated in figure-5. When galvanometer in under the influence of an external source, an electrical signal through the coil causes galvanometer to rotate accordingly. <\/span>Light beam from the light source gets reflected from the galvanometer mirror and falls on to the recording surface, which is in proportion to the amplitude and to the rate change of the input signal being recorded.<\/span><\/p>\n<\/div>\n

                  \"\"<\/p>\n

                  \n

                  Figure 5<\/strong>. Galvanometeric Chart Recorder<\/p>\n

                   <\/p>\n

                  More than one galvanometer can be used for recording data. To avoid confusion between overlapped recordings, the traces are identified by printing series of number corresponding to the galvanometer position on the edge of the film. In this system, a transmitted light from the source is passes through a numbered film wheel on to a paper. Reference grid lines are recorded by passing a some of the light through a grid line aperture that allows a series of fine bars of light moving sequentially in the same direction as the record travels, and gets exposed on to the record simultaneously with the galvanometer traces.<\/p>\n

                   <\/p>\n

                  CRT Recorders<\/strong><\/span><\/p>\n

                   <\/p>\n

                  These are 4 dimensional display and recording devices. The two axes are conventional ones i.e. X-axis and Y-axis. The third axis is Z-axis that can be identified by spot identity on display media or recoding surface. Y\u2019(Y Prime)-axis is the fourth axis which is the movement of the recording medium. A block diagram of CRT is shown in figure 6.<\/p>\n

                   <\/p>\n

                  As the name implies, here a cathode ray tube is used and its output light gets focused on the record either by an optical lens or by using a fiber optic face plate on the CRT and the record is kept in contact with the fiber optic.<\/p>\n<\/div>\n

                  \"\"<\/p>\n

                   <\/p>\n

                  Figure 6<\/strong>. Block diagram for CRT Recorder<\/p>\n

                   <\/p>\n

                  With CRT recorders data can be recorded 1000 time faster than the galvanometer recorder and because of the 4 axes they have the capability to record data continuously.<\/p>\n

                   <\/p>\n

                  Summary<\/strong><\/p>\n

                   <\/p>\n

                  In this module we studied about electronic recording devices.<\/p>\n

                    \n
                  1. In the introduction first we will briefly discussed about a data recording system and its types<\/li>\n
                  2. Under Graphic recorder we studied about Strip Chart Recorder, Circular Chart recorders and XY recorders<\/li>\n
                  3. In the end, we studied about Oscillographic Recorders and its types, Galvanometric recorder and CRT recorders<\/li>\n<\/ol>\n\n\n\n
                    you can view video on Recorders and Recording System I<\/strong><\/td>\n\"\"<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                    \u00a0 \u00a0\u00a0References :-<\/strong><\/p>\n

                      \n
                    1. Electrical and Electronic Measurements and Instrumentation, <\/span>Sawhney A. K.<\/em>, Dhanpat Rai & Sons, Reprint 1985<\/span><\/li>\n
                    2. Measurements and Instrumentation, Bakshi U.A., Bakshi A.V.,<\/em> Technical Publications, 2009<\/li>\n
                    3. Principles of instrumental analysis, Skoog, Douglas A., F. James Holler, and<\/em> Stanley R. Crouc,. <\/em>Cengage learning, Edition 2017<\/li>\n
                    4. Instrumentation, measurement and analysis. Nakra, B.C. and Chaudhry, K.K.,<\/em> Tata McGraw-Hill Education, 2003.<\/li>\n
                    5. Measurement and instrumentation: theory and application, Morris, A. S., &<\/em> Langari, R<\/em>. , Academic Press, 2012.<\/li>\n<\/ol>\n","protected":false},"author":3,"menu_order":3,"template":"","meta":{"_acf_changed":false,"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["prof-vinay-gupta"],"pb_section_license":""},"chapter-type":[],"contributor":[58],"license":[],"class_list":["post-52","chapter","type-chapter","status-publish","hentry","contributor-prof-vinay-gupta"],"part":3,"_links":{"self":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapters\/52","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/wp\/v2\/users\/3"}],"version-history":[{"count":7,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapters\/52\/revisions"}],"predecessor-version":[{"id":550,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapters\/52\/revisions\/550"}],"part":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapters\/52\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/wp\/v2\/media?parent=52"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/pressbooks\/v2\/chapter-type?post=52"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/wp\/v2\/contributor?post=52"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/msp04\/wp-json\/wp\/v2\/license?post=52"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}