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Explain the three main blocks of a solid state relay

Explain the three main blocks of a solid state relay

Answers

gregory
Solid-state relays
A solid-state relay conducts load current through one or more power transistors or
thyristors.
There are three main types of SSRs, classified by the type of input.
Reed-relay coupled SSRs send the input signal through the coil of a reed relay.
Closure of the reed switch triggers the thyristor into conduction.
Transformer-coupled SSRs send an ac control signal through the primary of a small
transformer. (In the case of dc control signals, the input first goes through a DC/AC
converter before hitting the transformer primary). Voltage from the transformer
secondary triggers the thyristor.
Finally, photo coupled SSRs isolate the input from the output through a
photosensitive diode or transistor. A control current actuates a light source which in
turn, lets a photosensitive semiconductor conduct trigger-current to actuate the power
device.
gregorymasila answered the question on February 22, 2018 at 16:51

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