From the course: Learning PLC Ladder Logic: 2 Diving Deeper

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ONS: One-shot instruction

ONS: One-shot instruction - Ladder Logic Tutorial

From the course: Learning PLC Ladder Logic: 2 Diving Deeper

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ONS: One-shot instruction

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- [Instructor] One Shot Instruction is an input instruction that allows an event to happen only once per scan and it requires a single tag of a Boolean type, either zero or one. One Shot Instruction is placed in the middle of the rung as an input instruction, so after the input XIC instruction in this case. And it's used to turn an output on for one program scan only. It is usually given an address. Every One Shot Instruction has a different address if we're using multiple ones during the program. When the logic or instructions ahead of the One Shot are true, the One Shot Instruction allows logical power to the instruction on its right, which is in this case is the output for exactly one scan. After the one scan, if the logic ahead of the One Shot is still true, the One Shot Instruction will not let the logical power through. When the logic ahead of the One Shot Instruction is false, the One Shot Instruction resets and…

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