This video gives basic information on Using the DEC "Decrement Value" 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 instruction is used to decrement the Element, shown here, by the whole value of 1. Now this is a power flow based instruction and not edge triggered. That means that as long as the input logic of the instruction is true the specified element will be reduced by 1 each and every PLC scan. That is why this instruction is Typically used with some type of edge triggered input logic. Here we are showing the operation with a leading edge one-shot contact. This allow for better control of the instruction.