pylon:
Do you have a schematics of your circuitry? What are the technical details of your relays? Links for them?
its a simple circuit. i am connecting my 3rd,5th,6th pin to led(getting good output). when i connect the same pins to relay and other pins of relay with 220v appliance as switch, it gets hanged up.
My understanding based on numerous posts in this forum, is that even if the Ardy can provide the current, it should be protected from any inductive device by a diode....
You certainly need a diode across the relay to absorb the EMF when you turn it off, and unless the relay coil draws less than 20mA you need to drive it via a transistor.
No you are not up to understanding it and it is not important and you will only arrive at the values you have now. This is not a critical part of the design. What is important is the circuit you use.
That is what you are failing to understand or even address.
Why complicate things with an optocoupler? You can do it with a relay, transistor, diode and a resistor. You could even get a solid state relay and drop the transistor and resistor.