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Why do we use opto-isolators in plc input circuits? can anyone show me a sketch of a typical opto-isolator and any other electronic components required to produce a TTL Logic1 inside a plc when an external input is raised to 24v DC? Whats the typical isolation voltage that such a system can with stand? Can anyone help this is my only hope!!!!!!!
Good grief. For isolation of course. I have not seen a PLC that does not have opto isolation built in for years. Any good PLC with have at least 2K isolation as standard.
Principally, the use of the opto-insolators is for eliminate easily a reability the electric interferences on the inputs and outputs of the PLC
as such as the higest peaks of currents, and electro magnetic fields