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<!DOCTYPE html><html class="writer-html5" lang="en" ><head> <meta charset="utf-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <title>STEP n°2: Measurement board — Ohmpi: open hardware resistivity-meter documentation</title><link rel="stylesheet" href="../_static/css/theme.css" type="text/css" /> <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> <!--[if lt IE 9]> <script src="../_static/js/html5shiv.min.js"></script> <![endif]--> <script id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script> <script src="../_static/jquery.js"></script> <script src="../_static/underscore.js"></script> <script src="../_static/doctools.js"></script> <script src="../_static/language_data.js"></script> <script async="async" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.7/latest.js?config=TeX-AMS-MML_HTMLorMML"></script> <script src="../_static/js/theme.js"></script> <link rel="index" title="Index" href="../genindex.html" /> <link rel="search" title="Search" href="../search.html" /> <link rel="next" title="STEP n°3: MUX board" href="V2_00_step_03.html" /> <link rel="prev" title="STEP n°1 : Raspberry Pi configuration" href="V2_00_step_01.html" /> </head><body class="wy-body-for-nav"> <div class="wy-grid-for-nav"> <nav data-toggle="wy-nav-shift" class="wy-nav-side"> <div class="wy-side-scroll"> <div class="wy-side-nav-search" > <a href="../index.html" class="icon icon-home"> Ohmpi: </a><div role="search"> <form id="rtd-search-form" class="wy-form" action="../search.html" method="get"> <input type="text" name="q" placeholder="Search docs" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form></div> </div><div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="Navigation menu"> <ul class="current"><li class="toctree-l1"><a class="reference internal" href="../Ohmpi.html">OhmPi project</a></li><li class="toctree-l1"><a class="reference internal" href="../V1_01.html">OhmPi V 1.01 (limited to 32 electrodes)</a></li><li class="toctree-l1"><a class="reference internal" href="../V1_02.html">OhmPi V 1.02 (limited to 32 electrodes)</a></li><li class="toctree-l1 current"><a class="reference internal" href="../V2_00.html">OhmPi V 2.xx (64 or 128 electrodes and 12V)</a><ul class="current"><li class="toctree-l2"><a class="reference internal" href="../V2_00.html#the-philosophy-of-ohmpi">The philosophy of Ohmpi</a></li><li class="toctree-l2"><a class="reference internal" href="../V2_00.html#technical-data">Technical data</a></li><li class="toctree-l2 current"><a class="reference internal" href="../V2_00.html#ohmpi-2-step-by-step">Ohmpi 2 step by step</a><ul class="current"><li class="toctree-l3"><a class="reference internal" href="V2_00_step_01.html"><strong>STEP n°1</strong> : Raspberry Pi configuration</a></li><li class="toctree-l3 current"><a class="current reference internal" href="#"><strong>STEP n°2</strong>: Measurement board</a><ul><li class="toctree-l4"><a class="reference internal" href="#part-a-assembly-of-measurement-board"><strong>PART A</strong> Assembly of measurement board</a></li><li class="toctree-l4"><a class="reference internal" href="#part-b-start-up-of-the-measurement-board"><strong>PART B</strong> Start-up of the measurement board</a></li><li class="toctree-l4"><a class="reference internal" href="#part-c-check-the-measurement-board"><strong>PART C</strong> Check the measurement board</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="V2_00_step_03.html"><strong>STEP n°3</strong>: MUX board</a></li></ul></li></ul></li></ul> </div> </div> </nav> <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap"><nav class="wy-nav-top" aria-label="Mobile navigation menu" > <i data-toggle="wy-nav-top" class="fa fa-bars"></i> <a href="../index.html">Ohmpi:</a> </nav> <div class="wy-nav-content">7172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140
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<div class="section" id="step-n2-measurement-board">
<h1><strong>STEP n°2</strong>: Measurement board<a class="headerlink" href="#step-n2-measurement-board" title="Permalink to this headline">¶</a></h1>
<div class="section" id="part-a-assembly-of-measurement-board">
<h2><strong>PART A</strong> Assembly of measurement board<a class="headerlink" href="#part-a-assembly-of-measurement-board" title="Permalink to this headline">¶</a></h2>
<div class="section" id="required-components">
<h3>Required components<a class="headerlink" href="#required-components" title="Permalink to this headline">¶</a></h3>
<div class="align-center figure">
<a class="reference internal image-reference" href="../_images/00_mes_board_components.jpg"><img alt="alternate text" src="../_images/00_mes_board_components.jpg" style="width: 600px; height: 450px;" /></a>
</div>
<table class="colwidths-given docutils align-default" id="id1">
<caption><span class="caption-text">List of components</span><a class="headerlink" href="#id1" title="Permalink to this table">¶</a></caption>
<colgroup>
<col style="width: 8%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 9%" />
<col style="width: 9%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Component</p></th>
<th class="head"><p>Number</p></th>
<th class="head"><p>Cost per unit €</p></th>
<th class="head"><p>Total cost €</p></th>
<th class="head"><p>Manufacturer</p></th>
<th class="head"><p>Manufacturer s reference</p></th>
<th class="head"><p>Web reference</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p>Raspberry Pi 4 Model B</p></td>
<td><p>1</p></td>
<td><p>58.75</p></td>
<td><p>58.75</p></td>
<td><p>Raspberry</p></td>
<td><p>Raspberry Pi 4 Model B</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Seeed-Studio/102110421?qs=7MVldsJ5UaxeN3LYyh3sqw%3D%3D">https://www.mouser.fr/ProductDetail/Seeed-Studio/102110421?qs=7MVldsJ5UaxeN3LYyh3sqw%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>LM158N AMP-o</p></td>
<td><p>4</p></td>
<td><p>14.5</p></td>
<td><p>58</p></td>
<td><p>Texas Instruments</p></td>
<td><p>LM358AN/NOPB</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Texas-Instruments/LM158J?qs=X1J7HmVL2ZH8vpEfMl8%2FFQ%3D%3D">https://www.mouser.fr/ProductDetail/Texas-Instruments/LM158J?qs=X1J7HmVL2ZH8vpEfMl8%2FFQ%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Printed circuit board</p></td>
<td><p>1</p></td>
<td><p>12</p></td>
<td><p>12</p></td>
<td><p>Asler</p></td>
<td><ul class="simple">
<li></li>
</ul>
141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210
</td>
<td><ul class="simple">
<li></li>
</ul>
</td>
</tr>
<tr class="row-odd"><td><p>ADS1115</p></td>
<td><p>2</p></td>
<td><p>11.9</p></td>
<td><p>23.8</p></td>
<td><p>Adafruit</p></td>
<td><p>1085</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Adafruit/1085?qs=%2Fha2pyFaduhE%2FOGzuTWIQ9Iz5VjaqFOYugqAlGxpEcKiGrQvF4hn%252Bg%3D%3D">https://www.mouser.fr/ProductDetail/Adafruit/1085?qs=%2Fha2pyFaduhE%2FOGzuTWIQ9Iz5VjaqFOYugqAlGxpEcKiGrQvF4hn%252Bg%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Capacitor 100nF 50Vdc 10% Ceramic</p></td>
<td><p>4</p></td>
<td><p>0.2</p></td>
<td><p>0.8</p></td>
<td><p>KEMET</p></td>
<td><p>C320C104K1</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/KEMET/C320C104K1R5TA7303?qs=c4UyoTs%2FLq1th4mcyOeTmA%3D%3D">https://www.mouser.fr/ProductDetail/KEMET/C320C104K1R5TA7303?qs=c4UyoTs%2FLq1th4mcyOeTmA%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>Resistor 1 Kohm 0.5W +- 0.1%</p></td>
<td><p>2</p></td>
<td><p>1.3</p></td>
<td><p>2.6</p></td>
<td><p>TE Connectivity</p></td>
<td><p>H81K0BYA</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/TE-Connectivity-Holsworthy/H81K0BYA?qs=%2Fha2pyFaduhUylh7Az%2FmjFH2XjOUms6wZtUX4sOM%252BII%3D">https://www.mouser.fr/ProductDetail/TE-Connectivity-Holsworthy/H81K0BYA?qs=%2Fha2pyFaduhUylh7Az%2FmjFH2XjOUms6wZtUX4sOM%252BII%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Resistor 1.5 Kohms +- 0.1%</p></td>
<td><p>2</p></td>
<td><p>1.3</p></td>
<td><p>2.6</p></td>
<td><p>TE Connectivity</p></td>
<td><p>H81K5BYA</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/TE-Connectivity-Holsworthy/H81K5BYA?qs=%2Fha2pyFadugy9tWham3rU9HmIJOhyWhBIN95kNm%252BX%2FM%3D">https://www.mouser.fr/ProductDetail/TE-Connectivity-Holsworthy/H81K5BYA?qs=%2Fha2pyFadugy9tWham3rU9HmIJOhyWhBIN95kNm%252BX%2FM%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>Resistor 1.5 Kohms +- 5%</p></td>
<td><p>2</p></td>
<td><p>1.3</p></td>
<td><p>2.6</p></td>
<td><p>Vishay</p></td>
<td><p>CCF071K50GKE36</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Vishay-Dale/CCF071K50GKE36?qs=QKEOZdL6EQpA6LZRLQFVOw%3D%3D">https://www.mouser.fr/ProductDetail/Vishay-Dale/CCF071K50GKE36?qs=QKEOZdL6EQpA6LZRLQFVOw%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Resistor 10 Mohms +-5%</p></td>
<td><p>2</p></td>
<td><p>0.762</p></td>
<td><p>1.524</p></td>
<td><p>VISHAY</p></td>
<td><p>CMF651M0000FKEK143</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Vishay-Dale/CMF651M0000FKEK143?qs=CiayqK2gdcKzIA2LEVaLkg%3D%3D">https://www.mouser.fr/ProductDetail/Vishay-Dale/CMF651M0000FKEK143?qs=CiayqK2gdcKzIA2LEVaLkg%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>2 ohm shunt resistor+- 1%</p></td>
<td><p>1</p></td>
<td><p>2.42</p></td>
<td><p>2.42</p></td>
<td><p>Ohmite</p></td>
<td><p>41F2R0E</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Ohmite/41F2R0E?qs=IM6ToxQzGOAuEDprb19mHA%3D%3D">https://www.mouser.fr/ProductDetail/Ohmite/41F2R0E?qs=IM6ToxQzGOAuEDprb19mHA%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Dual screw terminal (5.08-mm pitch)</p></td>
<td><p>5</p></td>
<td><p>0.648</p></td>
<td><p>3.24</p></td>
<td><p>CUI Devices</p></td>
<td><p>TB009-508-02BE</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/CUI-Devices/TB009-508-02BE?qs=vLWxofP3U2wCFk5uCkWTkA%3D%3D">https://www.mouser.fr/ProductDetail/CUI-Devices/TB009-508-02BE?qs=vLWxofP3U2wCFk5uCkWTkA%3D%3D</a></p></td>
</tr>
211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280
<tr class="row-odd"><td><p>DC/DC converter 12 to 24V</p></td>
<td><p>2</p></td>
<td><p>15.58</p></td>
<td><p>31.16</p></td>
<td><p>TracoPower</p></td>
<td><p>TRN 3-1215</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/TRACO-Power/TRN-3-1215?qs=YCa%2FAAYMW02gqUicGQj0tA%3D%3D">https://www.mouser.fr/ProductDetail/TRACO-Power/TRN-3-1215?qs=YCa%2FAAYMW02gqUicGQj0tA%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>DIP Dual In Line Socket 2*4</p></td>
<td><p>3</p></td>
<td><p>0.72</p></td>
<td><p>2.16</p></td>
<td><p>Mill-Max</p></td>
<td><p>110-43-308-41-001000</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Mill-Max/110-43-308-41-001000?qs=IGgAdOvCTsTu%2FqaUr8NArg%3D%3D&mgh=1&vip=1&gclid=EAIaIQobChMIn_TAxbCx8wIVQ5nVCh2QaQFpEAYYCCABEgJk1_D_BwE">https://www.mouser.fr/ProductDetail/Mill-Max/110-43-308-41-001000?qs=IGgAdOvCTsTu%2FqaUr8NArg%3D%3D&mgh=1&vip=1&gclid=EAIaIQobChMIn_TAxbCx8wIVQ5nVCh2QaQFpEAYYCCABEgJk1_D_BwE</a></p></td>
</tr>
<tr class="row-odd"><td><p>AQY211EH</p></td>
<td><p>4</p></td>
<td><p>3.84</p></td>
<td><p>15.36</p></td>
<td><p>Panasonic Industrial Devices</p></td>
<td><p>AQY211EH</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Panasonic-Industrial-Devices/AQY211EH?qs=wKtUvITRialGIU8hcM7DvQ%3D%3D">https://www.mouser.fr/ProductDetail/Panasonic-Industrial-Devices/AQY211EH?qs=wKtUvITRialGIU8hcM7DvQ%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>DIP Dual In Line Socket 2*2</p></td>
<td><p>4</p></td>
<td><p>0.449</p></td>
<td><p>1.796</p></td>
<td><p>Preci-dip</p></td>
<td><p>110-83-304-41-001101</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Preci-dip/110-83-304-41-001101?qs=%2Fha2pyFadujQKqx4wAuiG%2FMGNdxMCNv%2F33Nj0gBxRocuLUcYnpyONg%3D%3D">https://www.mouser.fr/ProductDetail/Preci-dip/110-83-304-41-001101?qs=%2Fha2pyFadujQKqx4wAuiG%2FMGNdxMCNv%2F33Nj0gBxRocuLUcYnpyONg%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>SSQ-103-03-G-D</p></td>
<td><p>1</p></td>
<td><p>2.06</p></td>
<td><p>2.06</p></td>
<td><p>Samtec</p></td>
<td><p>SSQ-103-03-G-D</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Samtec/SSQ-103-03-G-D?qs=rU5fayqh%252BE2Z%252BZTchcPoHQ%3D%3D">https://www.mouser.fr/ProductDetail/Samtec/SSQ-103-03-G-D?qs=rU5fayqh%252BE2Z%252BZTchcPoHQ%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>MCP23008</p></td>
<td><p>1</p></td>
<td><p>1.72</p></td>
<td><p>1.72</p></td>
<td><p>Adafruit</p></td>
<td><p>593</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Adafruit/593?qs=sGAEpiMZZMsKEdP9slC0YYV4kPdpMD1Hts4SLctIVmw%3D">https://www.mouser.fr/ProductDetail/Adafruit/593?qs=sGAEpiMZZMsKEdP9slC0YYV4kPdpMD1Hts4SLctIVmw%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>Header sets 1x10</p></td>
<td><p>2</p></td>
<td><p>2.12</p></td>
<td><p>4.24</p></td>
<td><p>Samtec</p></td>
<td><p>SSW-110-02-G-S</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Samtec/SSW-110-02-G-S?qs=rU5fayqh%252BE0w1ORXZiBQpw%3D%3D">https://www.mouser.fr/ProductDetail/Samtec/SSW-110-02-G-S?qs=rU5fayqh%252BE0w1ORXZiBQpw%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>SMT Breakout PCB for SOIC-8</p></td>
<td><p>1</p></td>
<td><p>2.5</p></td>
<td><p>2.5</p></td>
<td><p>Adafruit</p></td>
<td><p>1212</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Adafruit/1212?qs=GURawfaeGuCAqqfvnVtyeg%3D%3D&mgh=1&vip=1&gclid=EAIaIQobChMIt8zJzr6x8wIVGdnVCh2vBwVsEAQYAyABEgJqG_D_BwE">https://www.mouser.fr/ProductDetail/Adafruit/1212?qs=GURawfaeGuCAqqfvnVtyeg%3D%3D&mgh=1&vip=1&gclid=EAIaIQobChMIt8zJzr6x8wIVGdnVCh2vBwVsEAQYAyABEgJqG_D_BwE</a></p></td>
</tr>
<tr class="row-odd"><td><p>INA282AID</p></td>
<td><p>1</p></td>
<td><p>4.11</p></td>
<td><p>4.11</p></td>
<td><p>Texas Instruments</p></td>
<td><p>INA282AID</p></td>
281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Texas-Instruments/INA282AID?qs=Ze4%2FuFuz19ILFayZXOCfrA%3D%3D">https://www.mouser.fr/ProductDetail/Texas-Instruments/INA282AID?qs=Ze4%2FuFuz19ILFayZXOCfrA%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>THD 15-1211N</p></td>
<td><p>1</p></td>
<td><p>39.72</p></td>
<td><p>39.72</p></td>
<td><p>TracoPower</p></td>
<td><p>THD 15-1211N</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/TRACO-Power/THD-15-1211N?qs=%2Fha2pyFadugpyEG4IDvm%2FMSR%252B7aN%2F0T3rUIs9PCAqJlT4%252BnRpUOOeQ%3D%3D">https://www.mouser.fr/ProductDetail/TRACO-Power/THD-15-1211N?qs=%2Fha2pyFadugpyEG4IDvm%2FMSR%252B7aN%2F0T3rUIs9PCAqJlT4%252BnRpUOOeQ%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>DIP Dual In Line Socket 2*20</p></td>
<td><p>1</p></td>
<td><p>8.53</p></td>
<td><p>8.53</p></td>
<td><p>Samtec</p></td>
<td><p>SSQ-120-23-G-D</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Samtec/SSQ-120-23-G-D?qs=rU5fayqh%252BE1BMVd%252BDZONqg%3D%3D">https://www.mouser.fr/ProductDetail/Samtec/SSQ-120-23-G-D?qs=rU5fayqh%252BE1BMVd%252BDZONqg%3D%3D</a></p></td>
</tr>
<tr class="row-even"><td><p>Pin strip no ejector</p></td>
<td><p>1</p></td>
<td><p>0.35</p></td>
<td><p>0.35</p></td>
<td><p>BLK electronic</p></td>
<td><p>10120550</p></td>
<td><p><a class="reference external" href="https://www.conrad.com/p/bkl-electronic-10120550-pin-strip-no-ejector-contact-spacing-254-mm-total-number-of-pins-6-no-of-rows-2-1-pcs-741435?searchTerm=741435&searchType=suggest&searchSuggest=product">https://www.conrad.com/p/bkl-electronic-10120550-pin-strip-no-ejector-contact-spacing-254-mm-total-number-of-pins-6-no-of-rows-2-1-pcs-741435?searchTerm=741435&searchType=suggest&searchSuggest=product</a></p></td>
</tr>
<tr class="row-odd"><td><p>Male Female spacer 2.5M HEXAGONALE</p></td>
<td><p> 4</p></td>
<td><p> 0.87</p></td>
<td><p> 3.48</p></td>
<td><p> HARWIN</p></td>
<td><p> R25-3002002</p></td>
<td><p> <a class="reference external" href="https://www.mouser.fr/ProductDetail/Harwin/R25-3002002?qs=W0yvOO0ixfENUv0hsdC4%2FQ%3D%3D">https://www.mouser.fr/ProductDetail/Harwin/R25-3002002?qs=W0yvOO0ixfENUv0hsdC4%2FQ%3D%3D</a></p></td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="description">
<h3>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h3>
<div class="align-center figure">
<a class="reference internal image-reference" href="../_images/schema_measurement_board.jpg"><img alt="alternate text" src="../_images/schema_measurement_board.jpg" style="width: 600px; height: 450px;" /></a>
</div>
<p>Figure shows the general schematics for the electronic measurement board developed.
We have developed a complete “plug and play” measurement board. To measure electrical resistivity with Raspberry Pi.
two ADS1115 were used,one for the voltage measurement one for the current measurement, as proposed by Florsch [7]. The ADS1115
is a 16-bit ADC (Analog-to-Digital Converter), with an adaptable gain. The advantage of ADS1115 is that the
input signal value could lie between - to + 6.114 V. For the current measurement we have directly integrated the INA282 component,
which allows to realize precise current measurement around a shunt resistor. The assembly are described in the following steps:</p>
<table class="docutils align-center">
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<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>1</p></td>
<td><img alt="../_images/01_mes_board.jpg" src="../_images/01_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Installation of female header, 1 by10 pins, for ADS1115</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>2</p></td>
<td><img alt="../_images/02_mes_board.jpg" src="../_images/02_mes_board.jpg" />
351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420
</td>
</tr>
<tr class="row-even"><td><p>Soldering of 4 dual-in-line- socket (2 by 2 pins) for
optical relay, AQY211EH.</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>3</p></td>
<td><img alt="../_images/03_mes_board.jpg" src="../_images/03_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering of 1 dual-in-line- socket (2 by 9 pins)
for INA282.</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>4</p></td>
<td><img alt="../_images/04_mes_board.jpg" src="../_images/04_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering of 1 dual-in-line- socket (2 by 4 pins)</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>5</p></td>
<td><img alt="../_images/05_mes_board.jpg" src="../_images/05_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering of 2 dual-in-line- socket (2 by 4 pins)</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>6</p></td>
<td><img alt="../_images/06_mes_board.jpg" src="../_images/06_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Traco Power Supply 12V to 5V, TDH15 - 1211N</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490
<tr class="row-odd"><td rowspan="2"><p>7</p></td>
<td><img alt="../_images/07_mes_board.jpg" src="../_images/07_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Four screw terminals for 12V inpout et 5V outpout</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>8</p></td>
<td><img alt="../_images/08_mes_board.jpg" src="../_images/08_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Traco power Supply 12V to 24V, TRN-1215</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>9</p></td>
<td><img alt="../_images/09_mes_board.jpg" src="../_images/09_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Two screw terminals electrodes M and N</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>10</p></td>
<td><img alt="../_images/10_mes_board.jpg" src="../_images/10_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Four screw terminals, for 12V power supply and for
electrodes A and B</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>11</p></td>
<td><img alt="../_images/11_mes_board.jpg" src="../_images/11_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering three capacitors (100nF)</p></td>
</tr>
</tbody>
</table>
<div class="admonition warning">
<p class="admonition-title">Warning</p>
<p>In this version, We used a shunt resistor of 2 ohms, which limits the current measurement to 48 mA. If the current is higher than this value, you just have to decrease the value of the shunt resistor.Change the shunt value in the code.</p>
</div>
<table class="docutils align-center">
491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>12</p></td>
<td><img alt="../_images/12_mes_board.jpg" src="../_images/12_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>2 ohms shunt resistor pre-adjustment</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>13</p></td>
<td><img alt="../_images/13_mes_board.jpg" src="../_images/13_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering 2 ohms shunt resistor</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>14</p></td>
<td><img alt="../_images/14_mes_board.jpg" src="../_images/14_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>1 Mohms resistors</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>15</p></td>
<td><img alt="../_images/15_mes_board.jpg" src="../_images/15_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering tow 1 Kohms resistors</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>16</p></td>
<td><img alt="../_images/16_mes_board.jpg" src="../_images/16_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering tow 1.5Kohms resistors</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>17</p></td>
<td><img alt="../_images/17_mes_board.jpg" src="../_images/17_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering tow 1.5Kohms resistors</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>18</p></td>
<td><img alt="../_images/18_mes_board.jpg" src="../_images/18_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Female header 2 by 20 pins for Raspberry Pi connection</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>19</p></td>
<td><img alt="../_images/19_mes_board.jpg" src="../_images/19_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>View of the female header 2 by 20 pins installation
for Raspberry Pi connection</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>20</p></td>
<td><img alt="../_images/20_mes_board.jpg" src="../_images/20_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Fixing MCP23008 component</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>21</p></td>
<td><img alt="../_images/21_mes_board.jpg" src="../_images/21_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting optical relay, AQY211EH</p></td>
</tr>
</tbody>
</table>
631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>22</p></td>
<td><img alt="../_images/22_mes_board.jpg" src="../_images/22_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting LM158 operational amplificator</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>23</p></td>
<td><img alt="../_images/23_mes_board.jpg" src="../_images/23_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting ADS115 board</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 13%" />
<col style="width: 87%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>24</p></td>
<td><img alt="../_images/24_mes_board.jpg" src="../_images/24_mes_board.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Fixing the INA282</p></td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="section" id="part-b-start-up-of-the-measurement-board">
<h2><strong>PART B</strong> Start-up of the measurement board<a class="headerlink" href="#part-b-start-up-of-the-measurement-board" title="Permalink to this headline">¶</a></h2>
<table class="docutils align-default">
<colgroup>
<col style="width: 100%" />
</colgroup>
<tbody>
<tr class="row-odd"><td><p><strong>Required components</strong></p></td>
</tr>
</tbody>
</table>
<table class="colwidths-given docutils align-default" id="id2">
<caption><span class="caption-text">List of components</span><a class="headerlink" href="#id2" title="Permalink to this table">¶</a></caption>
<colgroup>
<col style="width: 8%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 18%" />
<col style="width: 9%" />
<col style="width: 9%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Component</p></th>
<th class="head"><p>Number</p></th>
<th class="head"><p>Cost per unit €</p></th>
701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770
<th class="head"><p>Total cost €</p></th>
<th class="head"><p>Manufacturer</p></th>
<th class="head"><p>Manufacturer s reference</p></th>
<th class="head"><p>Web reference</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p>Spacer 3x11 mm</p></td>
<td><p>8</p></td>
<td><p>0.39</p></td>
<td><p>3.12</p></td>
<td><p>Wurth Elektronik</p></td>
<td><p>971110321</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/Seeed-Studio/102110421?qs=7MVldsJ5UaxeN3LYyh3sqw%3D%3D">https://www.mouser.fr/ProductDetail/Seeed-Studio/102110421?qs=7MVldsJ5UaxeN3LYyh3sqw%3D%3D</a></p></td>
</tr>
<tr class="row-odd"><td><p>Screw</p></td>
<td><p>4</p></td>
<td><p>0.305</p></td>
<td><p>1.22</p></td>
<td><p>APM HEXSEAL</p></td>
<td><p>RM3X8MM-2701</p></td>
<td><p><a class="reference external" href="https://www.mouser.fr/ProductDetail/APM-HEXSEAL/RM3X8MM-2701?qs=JJSE%2F12mKnS3VxSDrYXUHw%3D%3D">https://www.mouser.fr/ProductDetail/APM-HEXSEAL/RM3X8MM-2701?qs=JJSE%2F12mKnS3VxSDrYXUHw%3D%3D</a></p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>1</p></td>
<td><img alt="../_images/001.jpg" src="../_images/001.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Shutdown the raspberry Pi and unplug the power supply</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 10%" />
<col style="width: 90%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>2</p></td>
<td><img alt="../_images/001.jpg" src="../_images/001.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting the bottom spacers on the Raspberry Pi (male/female, 11mm, M3)</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 10%" />
<col style="width: 90%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>3</p></td>
<td><img alt="../_images/002.jpg" src="../_images/002.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting the upper spacers on the Raspberry Pi (female/female, 11mm, M3)</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>4</p></td>
<td><img alt="../_images/003.jpg" src="../_images/003.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting the Ohmpi’s measurement board on the Raspberry Pi</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>5</p></td>
<td><img alt="../_images/004.jpg" src="../_images/004.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Mounting the Ohmpi’s measurement board on the Raspberry Pi</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>6</p></td>
<td><img alt="../_images/005.jpg" src="../_images/005.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Plug the power supply into a socket and connect it to your
Raspberry Pi’s power port.</p></td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="part-c-check-the-measurement-board">
<h2><strong>PART C</strong> Check the measurement board<a class="headerlink" href="#part-c-check-the-measurement-board" title="Permalink to this headline">¶</a></h2>
<blockquote>
<div><p>Run the terminal, and write</p>
<div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="n">i2cdetect</span> <span class="o">-</span><span class="n">y</span> <span class="mi">1</span>
</pre></div>
</div>
</div></blockquote>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>1</p></td>
<td><img alt="../_images/i2cdetect.png" src="../_images/i2cdetect.png" />
</td>
</tr>
<tr class="row-even"><td><p>If everything is working, three I2C addresses should appear
on the screen.</p></td>
</tr>
</tbody>
</table>
<dl>
<dt>Setting up an equivalent electronic circuit, for this you will need:</dt><dd><ul class="simple">
<li><p>4 1kohm resistor (R2)</p></li>
<li><p>1 220 ohm resistor (R1)</p></li>
<li><p>1 small padboard</p></li>
<li><p>Spool of solder</p></li>
841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910
</ul>
<table class="docutils align-left">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>2</p></td>
<td><img alt="../_images/ref_circuit.png" src="../_images/ref_circuit.png" />
</td>
</tr>
<tr class="row-even"><td><p>Schematic of equivalent electronic circuit test</p></td>
</tr>
</tbody>
</table>
</dd>
</dl>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>3</p></td>
<td><img alt="../_images/20210905_122820.jpg" src="../_images/20210905_122820.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Prepare the equivalent electronic circuit test</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>4</p></td>
<td><img alt="../_images/20210905_123034.jpg" src="../_images/20210905_123034.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Prepare the battery connections and the terminals.</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>5</p></td>
<td><img alt="../_images/20210905_132856.jpg" src="../_images/20210905_132856.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Soldering cables and terminals</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>6</p></td>
<td><img alt="../_images/Inked20211206_150522_LI.jpg" src="../_images/Inked20211206_150522_LI.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Install the red cables on the +12V terminal and black cable
911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980
on the ground terminal.</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>7</p></td>
<td><img alt="../_images/Inked20211206_150522_LI2.jpg" src="../_images/Inked20211206_150522_LI2.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Connect the equivalent electronic circuit test</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>7</p></td>
<td><img alt="../_images/thonny_first_interface2.jpg" src="../_images/thonny_first_interface2.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Run Tonny Interpreter</p></td>
</tr>
</tbody>
</table>
<table class="docutils align-center">
<colgroup>
<col style="width: 12%" />
<col style="width: 88%" />
</colgroup>
<tbody>
<tr class="row-odd"><td rowspan="2"><p>7</p></td>
<td><img alt="../_images/20211206_144334.jpg" src="../_images/20211206_144334.jpg" />
</td>
</tr>
<tr class="row-even"><td><p>Run Ohmpi_4elec.py, if everything works you should
get the following result (220 ohm)</p></td>
</tr>
</tbody>
</table>
</div>
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