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Having problems to get a solid state relay to work

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Has anyone had problems getting a solid state relay to work?

After asking my friend,  I have learned some lessons:

  •     don't accidentally take out current limiting resistor
  •     solid state relay rated for AC load will probably just turn on small DC load.
  •     It makes a LOT of sense that since there's an LED inside you need a resistor, that's a Basic concept.

I'm using a SSR to control a AC load. To test it I'm using an LED load. The problem is, I can't get the relay to turn on. I'm using the S202S02 from Kynix.

First a was using a uP (Atmel XMEGA128A1) but that wasn't working so I switched to just straight up using Vcc. (Note: I didn't bother with a transistor, just connected it right to uP)

The SSR has 4 pins: the output pins (indicated by the AC tilde) and two input pins: + and -. The problem is that I apply vcc (3.3/5V) to plus, ground - and then connect one output pin to vcc and the other pin to an led which is connected to a resistor and then ground.


I know the led works because if I connect vcc to it it turns on.

What am I doing wrong? I'm pretty sure SSRs can switch DC loads.

I've used two different relays in my circuit so I don't think I have a bum relay.

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