{"id":45383,"date":"2019-09-29T10:20:40","date_gmt":"2019-09-29T04:50:40","guid":{"rendered":"https:\/\/ye1o34zhk8.onrocket.site\/?p=45383"},"modified":"2023-08-11T10:22:35","modified_gmt":"2023-08-11T04:52:35","slug":"plc-programming-examples","status":"publish","type":"post","link":"https:\/\/instrumentationtools.com\/plc-programming-examples\/","title":{"rendered":"PLC Programming Examples on Industrial Automation"},"content":{"rendered":"\n

Develop PLC Programming Examples<\/strong> on Industrial Automation according to the logic given below,<\/p>\n\n\n\n

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  1. A Saw, Fan and oil pump all go ON when a start button is pressed.<\/li>\n\n\n\n
  2. If the saw has operated less than 20s, the oil pump<\/a> should go off when the saw is turned off and the fan is to run for an additional 5s after the shutdown of the saw.<\/li>\n\n\n\n
  3. If the saw has operated for more than 20s, the fan should remain on until reset by a separate fan reset button and the oil pump should remain on for an additional 10 s after the saw is turned off.<\/li>\n\n\n\n
  4. Write a PLC program that will implement this process.<\/li>\n<\/ol>\n\n\n\n

    PLC Programming Examples<\/h2>\n\n\n
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    \"PLC<\/figure>\n<\/div>\n\n\n

    Program Description:<\/h3>\n\n\n\n

    Rung 0000:<\/h4>\n\n\n\n

    Start\/Emergency Stop PB latched with memory B3:0\/0.<\/p>\n\n\n\n

    Rung 0001:<\/h4>\n\n\n\n

    B3:0\/0 enabled to turn on Saw (O: 0\/0), Fan (O: 0\/1 ) and Oil pump (O:0\/2).<\/p>\n\n\n\n

    Normally closed contact of Stop switch<\/a> is in series Saw output to turn off.<\/p>\n\n\n\n

    Fan reset switch and Timer T4:0 is connected to turn off Fan when condition meets.<\/p>\n\n\n\n

    Timer T4:2 done a bit and memory bit is to turn off the oil pump.<\/p>\n\n\n\n

    Rung 0002:<\/h4>\n\n\n\n

    When the stop is pressed, according to the logic mentioned in point 2, Fan output (O: 0\/2) needs to turn off after 5s.<\/p>\n\n\n\n

    Comparator block restricts the timer T4:0 to run after the 20s of Saw operation.<\/p>\n\n\n\n

    Rung 0003:<\/h4>\n\n\n\n

    Timer T4:1 runs when the start is pressed. When the stop is pressed at any point after the 20s, Saw output will go off.<\/p>\n\n\n\n

    After 10s, the oil pump will go off. This operation is done by Timer T4:2. Timer T4:0 done bit is used to restrict the Timer<\/a> T4:1 operation when T4:0 is ON.<\/p>\n\n\n\n

    Rung 0004:<\/h4>\n\n\n\n

    Less than a comparator block<\/a> is used to perform the logic mentioned in point 2, to turn off Fan when saw output operation was less than 20s.<\/p>\n\n\n\n

    Program Output:<\/h2>\n\n\n\n

    Now we see the simulation of above ladder logic for different conditions as mentioned below.<\/p>\n\n\n\n

    When Start PB is pressed<\/h3>\n\n\n
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    \"PLC<\/figure>\n<\/div>\n\n\n

    When Stop switch pressed before the 20s<\/h3>\n\n\n
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    \"Motor<\/figure>\n<\/div>\n\n\n

    When Stop switch pressed after the 20s<\/h3>\n\n\n
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    \"Motor<\/figure>\n<\/div>\n\n\n

    When Fan reset switch is pressed<\/h3>\n\n\n
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    \"Fan<\/figure>\n<\/div>\n\n\n

    Conclusion:<\/h3>\n\n\n\n

    We can use this example to understand the programming logic in Allen Bradley PLC.<\/p>\n\n\n\n

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