apparentvj:
Hello,
First time I post here, so bear with me.I am bulding a circuit to dim an AC light. Already built the zero cross detector with H11AA1, this one works.
But the SSR will switch just from 12v. Tried with a BT137, can't get it working.My question is, How can I trigger 12v from the Arduino ?
Any suggestions are welcome .
Do you have the details of the SSR? Are you sure that it requires 12V? (DC, I assume.) It's fairly common for them to have a wide input voltage range, often 3VDC to 32VDC.
If it does, all you need is an NPN small-signal transistor connected in common-emitter configuration, with about a 10K resistor from the Arduino pin to the transistor base, and the SSR DC input connected between the transistor's collector and the 12V rail.