What would be the difference between a regular relay and a solid state relay?
What would be better/easier?
The regular (mechanical) relay is generally cheaper. They can usually handle more current and they don’t care as much about AC/DC. A solid state relay doesn’t have any moving parts, but if you aren’t toggling quickly, a mechanical relay can toggle enough times for it to not matter. Mechanical relays can toggle a few tens of thousands of times, so you will have a hard time breaking them if you turn them on and off at the start/end of a job.
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Thanks Jeffe, and what about wiring… it’s the same as a solid state relay?
I don’t really feel comfortable teaching about the relay wiring. If you know, then that’s fine. If you don’t know, then you should know that AC can hurt you, and I don’t feel right trying to explain everything you need to do it safely.
If you don’t know how to wire it, then you can search iot relay on amazon and come up with one that has the AC all isolated and in protective case, and you can just wire the trigger to the fan port.
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Hey Jeffe, I respect it! So a SSR is less dangerous?
No.
Take a look at this:
https://www.amazon.com/Iot-Relay-Enclosed-High-Power-Raspberry/dp/B00WV7GMA2
All the A/C is contained inside the plastic. The little green plug connects to the controller on the fan port, and you don’t have to change the firmware. There’s not any more chance of hurting yourself than a regular power strip.
These are mechanical relays, and they are a lot cheaper:
These will work. But they are controlled by 5V, and you have to cut the power cord that carries 120VAC. The result is a lot more dangerous. If you knew the dangers, and you were taking responsibility, then it’s fine. But if you’re asking about wiring, I would feel a lot better if you chose the power strip version.
The SSRs are very similar to the second choice.
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Thanks! Yes I’ve seen the power strip version… but I live in Europe and it’s not an European plug + 230V. I would have preferred it as well.
I will put everything in an official electronics enclosure. I’m just not an electronics guys, but I would like to learn. I am aware off the danger.
I do have wire strippers, crimpers and that kind of stuff. That’s what I’ve learned already 
To answer your question, the difference between a SSR and a EMR is that the SSR is effectively a transistor. The advantages are that it quieter, and generally the use less power to activate and can turn on and off faster. Disadvantages are they are more expensive and more sensitive to voltage spikes.
EMR (ELECTRO MECHANICAL RELAY) are basicly a normal switch that is activated by using an electromagnet. Advantages are that they are cheap and very reliable. Disadvantages are they are slow and louder… for this application I recommend a EMR but it will not make a substantial difference one way or the other.
And as Jeff said, be careful with the wiring. Both for your immediate safety. But also the long term safety of the system, your property, and yourself.
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Thanks for the explanation! Before I wire up everyting, I will make a drawing and let it check by others.
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just so you know, a lot of the danger comes not from how its wired (as its basically a switch) but rather the quality of the wiring. think of it like wiring an outlet for your house, its easy to put the wires in the right spot, its a lot harder to make it safe to be used. meaning things like how much insulation is stripped, loos strands of wire, the angle that the wires enter the box and relay terminal, the torque you place on the screws in the terminal block, etc. if you know someone who is familiar with house voltage (an electrician or a service tech that deals with electricity regularly) i would have them look over the device once you have it wired, before putting power to it.
At work I have colleagues who are electricians, so I can ask them. But know with this COVID19, I don’t see them as often…
I’m also looking for tutorials for an electronics enclosure and there are a lot. But I have a hard time finding in depth guides and tutorials, anyone has some good tutorials?
you could always try sending them pictures of the completed wiring, not as good as seeing it in person but its better than nothing 
also are you looking for a how to make the enclosure? or rules on how to make it safe?
I have an offcial electornics enclosure 40x30cm, but I would like a tutorial about what the possablitities are to put in it… like a relay, emergency stop, a led light, fans and other stuff.
What I have so far is a MKS Sbase board and a 24VDC MeanWell powersupply… but they are not in an enclosure yet. I also bought some GX16 aviation pluggs to connect the stepper motors and a plugg for a USB cable.
ahh well for designing your enclosure is largely personal preference. i used to design industrial controls for HVAC equipment and even in the professional world there where 1000 ways to approach it, limited only by the codes and certifications you wanted it to have (here in the US that was mostly ETL, UL, and NEC). my recommendation is to do your research, find one that you like (look, usability, price range, and skill level) and copy that general design. there are some really good examples of enclosure builds here on the forum. so spend some time looking through the “your builds” section (both for the MPCNC and LRv2) as those will have most of the electronics and options you will have on your machine.
the most common things i see, are options for the screen, plugs for all the wiring, and E stop buttons/switches.
Thanks, I will do some research!
I have a question:
I have a MKS Sbase board which takes 12V-24VDC, and I got it powered by 24VDC.
If I use the the BED, E1, E2 and Fan connectors… is the output also 24VDC?
So if I want to connect a fan for example, it has to be a 24V fan?
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Yes.
Yes. 24V DC fan.
There are other pins that have very little current capacity, but they will be 5V. If you just need a digital signal at 5V, you can use one of those and turn them on with M42.
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Thanks Jeffe,
I ordered some mechanical relay’s, the same one as you suggested just a different brand.
Now I found this:
it’s a picture from this web page:
http://microfabricator.com/articles/view/id/53a548013139440e2c8b456e/shapeoko-upgrade-quiet-cut-spindle-with-gshield-and-relay
So I need 3 pins from my board, 5V, GND and a digital pin… so how does it translate to my board?
A 5V and a GND I can find… but which one are digital pins?
Whatever one you want. I would personally use one of the endstop pins that I didn’t need. That has 5V, a pin, and a ground in one spot.
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Thnanks, Yes I thought so too!
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Today I will recieve my 24V LED strip, I will put this in my Enclosure to get a lot more light in. It’s pretty dark now.
So I want to connect the LED strip to the BED/E1/E2 pins, the FAN pins I want to use for my fan(s) who I ordered. The LED strip is just a (warm) white color with black and red wire. Can I just connect it to one of the outputs (BED/E1/E2)? And how do I turn them ON and OFF? And do I need to set something in the firmware?