This video gives basic information on Using the UDCG "Global UP/Down Counter" instruction in the Do-more Designer software. It presents information that is commonly missed by users. This WILL NOT be a complete tutorial for the instruction but rather a supplement to the help file and customer experience.
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This type of counter instruction is used to counter act the termination behavior of ladder code. With other counter instructions if the code block or stage is ended the counter could be reset. If the code block or stage that contains a Global Up down counter is terminated the counter structure will retain the last state. This instruction has 2 input rungs. One for UP and One for down. Both of these are edge triggered. This is indicated by the arrow on the input leg. This counter has two presets, one for up and one for down count. When the count is equal or greater that the up preset, the .done bit will turn on. When the count is equal to or less than the down preset, the down DONE bit will turn on. To reset this type of counter you must use the Reset counter instruction. AS with other counters, this reset takes priority over inputs, so the reset must be turned off prior to counting.