Uploaded August 2026 | Updated September 2026, 1 hour ago

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What major parts go into a solid state relay and why …
↓↓↓ Complete description, time index and links below ↓↓↓

Have you ever wondered how solid-state relays work? In this video we’ll recreate step by step the functionality of an electromechanical relay with electronic, that is solid state, components.

First we have a look at an electromechanical relay. Then we try to replace it with a MOSFET. A second MOSFET enables us to switch AC. An additional optocoupler ensures galvanic isolation. Finally we add a resistor to discharge the MOSFET gates.

00:00 Intro – replacing a relay with solid state components
00:40 Electromechanical Relay – solenoid and contactor
01:30 One MOSEFT – not blocking current in both directions
08:50 Another MOSFET – to block current in both directions
11:53 Optocoupler – isolation between load and control circuit
19:14 Resistor – simplest way to discharge MOSFET gates
20:36 Wrap-Up – next up are the details, bye

Tutorials youtube.com/playlist?list=PLwq-2MnM58FKn3920rc1V0qoTsQDheTIw
Solid-State Relays – The Details (1) youtu.be/GqKWDCzrX-I
Solid-State Relays – The Details (2) youtu.be/RecJYUTf5-g

#mosfet #optocoupler #photovoltaic #tutorials #tutorial #how-to #robertssmorgasbord