This video gives basic information on Using the TMRDOWN "Down Timer" 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 is a multi-scan instruction, because it takes multiple scans to complete, it cannot be used in either Subroutines or Interrupt Service Routines. It can used in Programs and under special circumstances can also be used in Stages inside of a Program or in Tasks. See the help topic “Instruction Set Chart” for more information. This instruction has one power rail connection that works for both the Enable and Reset. If the rung is true it will enable the timer and start counting down from the preset value. If this rung is false it will reset the timer count to equal the preset. When the timer is equal to zero the done bit will turn on.