I am unable to understand how does galvanic isolation work either via an optocoupler or a transformer. In an optocoupler, the input side current caused LED to emit infra red light which basically switches on the photo transistor on the output side. In case of any voltage surge on the input side or any noise, the input current will vary henceforth the light output and thus the collector current on the output. So how does isolation works? Or am i missing something really basic. Similarly for the transformer.
Electronic – How does Galvanic isolation work
isolationopto-isolatortransformer
Related Topic
- Electronic – How to do A/D conversion with isolation
- Electronic – arduino – How to fix Arduino optocoupler + LED that doesn’t light up
- Electronic – Grounding a 30KVA isloation transformer
- Electronic – How to adjust output resistance with galvanic isolation
- Electronic – Relevance of Galvanic Isolation of Boost Converters
- Electronic – PoE galvanic isolation necessary
Best Answer
The point of isolation is to provide a facsimile on the output of what appears on the input yet floating from the input.
For example you want to generate a 5V sine wave from the mains. A suitable transformer will do this for you and will allow you to tie one side to earth making an inherently safe voltage. Without the isolation the output could be potentially fatal.
In other cases we do not need an accurate representation of the input just a digital signal to say for example "Is the mains more than 90V?". An Opto is likely to be used for this but would allow this information to be passed safely to the output.