What are a solid-state relay and the major applications of the solid-state relay?

The solid-state relay or commonly known as the SSR is an electronic switch when the small external electrical voltage passes through the terminals of the SSR. The relay can be designed for the intended purpose like AC or DC based on the requirement. The functions of the solid-state relay are precisely the same as the electromechanical relay, and the only aspect which makes the solid-state relay different from the electromechanical relay is it does not contain any moving parts.

Instead of the moving parts, the solid-state relays use semiconductor devices like thyristors and transistors to switch the power-up and up to a hundred amperes at a time. The solid-state relays or the SSR also possess faster switching speeds when compared to the electromechanical relays. The SSR also does not create any physical wear out like the electromechanical relay. The solid-state relay also provides limited arrangements, not like the electromechanical relays.

The significant advantages of the solid-state relay

• The solid-state relay has a slim body and can allow tight packing to the users.
• They also offer a silent operation as no noise is created like the electromechanical relay.
• The SSR switching time is much faster than that of the electromechanical relay. The switching time is the time taken for the LED to turn ON and OFF, which is measured in micro and milliseconds.
• They can also offer an increased and more prolonged life as they do not use any physical moving parts. Due to the non-availability of the material moving parts, they are also affordable, and the users are also free from the maintenance cost of the moving parts.
• The amount of resistance at the output always remains constant and does not depend on the amount of use of the relay.

The significant disadvantages of the solid-state relay

• The whole device of the SSR is also at risk of spurious switching due to the voltage. The entire transition process is carried at a good pace.
• The SSR also offers isolated and a biased supply to the entire gate charge circuit.
• The SSR also has more significant chances for a shorten output termed as fail, while the electromechanical relay can have more extended output termed as open.