solid state relay question

File: IMG_20170228_174646229.jpg (825KB, 1000x935px) Image search: [Google]

825KB, 1000x935px

It's a subpar diagram to put it lightly, but it will work for my purposes.

CCS is a cycle control switch, by the way

>>1138036
It will work with AC only.

>>1138036
Your SSR is for AC which means it's probably SCR based. You need a DC switching SSR which would be FET based.

If you were trying to switch AC below 24 volts the SCR's would never trigger thus the SSR would not conduct.

Note that the chinese SSRs are almost all fake and will catch fire if run at anywhere near their rated current.

I wouldn't put more than 5A though a 40A chinese SSR.

>>1138030
Chinese SSR are rated as twice as much it can actually handle.
So, don't use it with more than 20a

Also, AC SSR only triggers at the beggining of the wave. So it has to start or cross 0V

>>1138091
>Also, AC SSR only triggers at the beggining of the wave. So it has to start or cross 0V
No they don't. An SCR can fire at any non-zero point in the waveform but can only unlatch at zero (when there is no current flow). Maybe that's what you're thinking. That's how SCR based AC dimmers work. They chop the front of the waveform off.

>>1138036
Just use a electomechanical relay.

>>1138099
Thread

>>1138099
or a big mosfet, trigger it with an opto if you need isolation

>>1138099
Isn't there a higher switching delay with EM relays? Also a risk of arcing with high amperage?

>>1138248
You've got a motor in the circuit and you're worried about switching noise?

>>1138252
Not noise. Delay. And damage to the contacts from arcing.

This is a controller circuit for airsoft, and based on my battery and motor, I'm guessing I'm going to hit at least 30rps, meaning 1 round every 30ish ms.

The code on the duino makes it select fire and the CCS needs to be able to shut off the motor with as little delay possible. My code shouldn't be an issue here. I'm worried about the actual shutoff delay of the em relay

>>1138254
I've worked with SSRs and you need a resistor across the input to help with the turn off delay. Some of them have tons more delay than an EMR.

>>1138256
Huh. What's the lifetime on the mechanical relays? Is arcing going to be as much of an issue as I'm making it to be, or am I retarded?

Also, do they make em relays in a small enough form factor that I could actually fit it inside my shell?

>>1138262
don't forget a flyback diode on the relay or you will fry any chips/arduinos when the relay switches off.

>>1138098
Zero-cross turn-on is a common feature in SSRs. Zero-cross turn-off is a byproduct of using TRIACs or SCRs, like you said.

>>1138262
Depends on relay, but 100000 cycles at full (resistive) load would be quite typical. Inductive loads like motors can shorten the life significantly, but with proper arc suppression (snubbers, varistors) the difference to resistive loads isn't that big.

>>1138036
Is this a picture of a screen?...

And you are a "coder"?

>>1138360
Yes and yes.

I'm a software developer. With a CS degree.

And it's a picture of a screen because the company I work for are fascists about copying files to external media or emailing to outside addresses.

Also 4Chan is blocked so I'm on mobile. Fight me.

>>1138360
Go back to /g/.