MECHANICAL relay V.S. SOLID-STATE relay (clearly explained)

When it comes to switching things on and off, there are many options. In this video, I describe the similarities and differences between two of those options: mechanical relays and solid-state relays. My personal preference is toward the solid-state devices because of how practical and easy to use they are!

I am curious if anyone can think of a use case where a mechanical relay would be more suitable. What do you think?

[moonbeammimi]

Great explanation! I'm not an electrically "literate" person and I've been looking for solid state vs mechanical relays info because I'm evaluating kilns for purchase. This video has helped a lot!

[kayzrx]

mechanical is typically more efficient and cost effective when you consider higher loads. the SSR will need to reject a lot of heat due to voltage drop across it. Hence whey they need a heat sink.

[jlwasmer]

What's the resistance of the SSR on its OUTPUT? It seems no one addresses the impact of an SSR on the circuit it controls.

[allynonderdonk]

My SSR for compressor application gives off crazy heat(yes it is rated correctly) pulls 12 amps on one side puts out 9 on the other. Contactor or relay gets a thumbs up in my book a lot of the time.

[MrTomasMaliauka]

You can not turn your AC SSR 1000 times per second. Most likely your AC SSR is made of a TRIAC. You can turn the TRIAC ON, but you can not turn it OFF. It turns itself OFF at the end of every half of AC cycle. You can not turn AC SSR ON more times than it turns itself OFF. So, you can turn it on not more than 100 times in Europe and 120 times in USA.

[damianbutterworth]

I used one of them big SSR for switching the immersion heater on when my solar battery pack was fully charged. a 24 volt 1000 watt immersion. I also came across back EMF when I made an arduino watering system for the greenhouse. I used mini shield relays to switch on12 volt dc solenoid water values and when it turned off it spiked the arduino which reset itself. Used a diode like you.

[arthurrae]

Can either a Solid State or Mechanical Relay be used on a job where it needs to be on for several minutes & only off for several seconds before being on again, over and over; and still work with integrity?

[billnj]

I think mechanical relays will continue to be used in low speed copier equipment to control paper feed rollers. Unless they use a dedicated motor for each roller. This could be expensive. But I see the advantage of using solid state relays. Thank you for sharing!

[PRBB]

Umm, I was hoping for more Information of the internal workings of the SSR.

[MrTomasMaliauka]

You can turn DC SSR ON and OFF thousands of times per second though, because it made of MOSFET. You can turn MOSFET ON and OFF buy controlling it's GATE terminal. Not the case in TRIAC's.

[bonifastarimo]

Help me please. our machine KODAK MAGNUS 400 CIRCUIT have fail ssr it burnt and i don't have the place where i can get a new one how can i make plan B for who u know help me please

[billwilliams]

CONTINUOUS LOAD, Does SSL Solid state relays use JFETS or MOSFETS? why are cars using SSL relays instead of Mechanical relays now? what are the advantages of using a SSL relay? do you use a current limiting resistor when apply power to a SSL relay to test out of circuit?

[OutOfNameIdeas]

You will blow your esp if you try and power a mechanical relay from a gpio. They are like 20-50ma max rated and relays are over double that when actuated. You always power it from the esp input voltage (power supply) 3.3 or 5v. NEVER FROM THE BOARD ITSELF.

Reason why people use machnical ones is most likely because they are half the price usually and while at it can usually handle way way more Amps than the solid state one.

[jrobles]

Sometimes you might have enough forward bias to switch a ssr state so you are forced to use a mechanical relay instead

[gerrymcerlean]

Ever heard of a MOSFET? That's what's inside your SSR and a MOSFET is much cheaper. If you don't want to have to solder, you can buy easy-connect MOSFET modules very cheaply on ebay.