Define opto-isolator. Explain the role of opto-isolator in PLC.

Define opto-isolator. Explain the role of opto-isolator in PLC.
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Answer :

An opto isolator is a device which consists of a light producing device such as LED and a light sensing element such as photo transistor. When a voltage is applied to LED, a light is produced which strikes the photo detector. The photo detector then changes its output. Optoisolator provides electrical isolation between input and output side. Opto isolator is an important part of I/O module of PLC. Both input and output module have Optoisolator to achieve electrical isolation between outside electrical circuit and PLC circuit.

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Answer :

Role of optoisolator in PLC: An optoisolator is a semiconductor device that uses a short optical transmission path to transfer an electrical signal between circuits or elements of a circuit, while keeping them electrically isolated from each other. Optocouplers can be used to isolate low-power circuits from higher power circuits and to remove electrical noise from signals. Electronic equipment, as well as signal and power transmission lines, are subject to voltage surges from radio frequency transmissions, lightning strikes and spikes in the power supply. To avoid disruptions, optoisolators offer a safe interface between high-voltage components and low-voltage devices.

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