# Designing an Solid State Relay

#### shosh

Joined Nov 14, 2011
5
Hi, im new to this forum
The reason I joined is because i need to design a solid state relay. Problem is, I'm not sure what it even is. During the semester, we touched on circuit analysis, mainly just RC circuits and really nothing beyond that. The course is kinda all over the place, touching on phase shifts and the like. seems like im unprepared to do this sort of thing. Can anyone be of assistance? any help would be greatly appreciated.

#### t_n_k

Joined Mar 6, 2009
5,455
In principle the SSR is an optically coupled / controlled isolated bi-lateral switch. So in creating a design you must incorporate those two ideas. An opto-coupler device would be probably be part of the design.

A triac can notionally conduct both ways so that might be an idea for the switching part.

Hope you like the forum.

Last edited:

#### shosh

Joined Nov 14, 2011
5
at the risk of sounding like a complete idiot, i'd have to ask what is the purpose of a relay? im only in my second year and this is the first real engineering course im taking.

the circuit actually seems simple enough, but my working experience are with ic chips and simple logic design so far with batteries as a power source.

http://idobartana.com/hakb/SSR/circuit.html

im guessing this is the circuit i need to build.

#### bountyhunter

Joined Sep 7, 2009
2,512
Hi, im new to this forum
The reason I joined is because i need to design a solid state relay. Problem is, I'm not sure what it even is.
optically coupled TRIAC

#### bountyhunter

Joined Sep 7, 2009
2,512
at the risk of sounding like a complete idiot, i'd have to ask what is the purpose of a relay?
1) low power circuit can switch high power AC load

2) control side is isolated from the AC

#### shosh

Joined Nov 14, 2011
5
Ok, so looking back, I have worked with a relay,a solenoid. Iirc,it was a device I can electronically control to open and close a switch. Naming states as NO,NC. So looking at that link I have, how would I drive a light bulb with that schematic?

Thx for yourhelp so far.

#### shosh

Joined Nov 14, 2011
5
any help? sorry for the impatience, but i need to accumulate parts this weekend.

So my main problem is hooking the SSR to a incandescent light bulb, or some sort of motor. I'd have to hook this up to an AC power source and i have never worked with AC power really, especially right out of a wall socket. Anyone guide me to a way to hook this up to a light bulb? specifically parts and materials i need. Also precautions, especially precautions.

#### praondevou

Joined Jul 9, 2011
2,942
any help? sorry for the impatience, but i need to accumulate parts this weekend.

So my main problem is hooking the SSR to a incandescent light bulb, or some sort of motor. I'd have to hook this up to an AC power source and i have never worked with AC power really, especially right out of a wall socket. Anyone guide me to a way to hook this up to a light bulb? specifically parts and materials i need. Also precautions, especially precautions.
Since you actually want to BUILD the circuit I don't think you will be able to get help here. Your circuit will not be isolated from mains which is a subject that's not allowed to be discussed on AAC, according to the ToS.

What you want to achieve is very easy, but without the necessary experience it's also dangerous. I really don't know why they would ask you to do this without even knowing the necessary components.