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I need help with choosing a Relay Switch for an Arduino Project.? Answered

I want to do a project in which i am able to control household appliances and in order to do that i know i need to use a Relay Switch but i have no idea how to select the Right one.
In my country 120 V is for residential use.I want to be able to turn on Lamps and other appliances using my Arduino board and would like to know how to choose the right kind of Relay Switch.



5 years ago

Forget relays, forget triacs , forget SSRs and wires and use the X-10 modules instead..
These devices use simple carrier wave control of each module through signals that are
super imposed on your AC power line house wiring and behave as slaves to the Arduino.

Have a look at these X10 remote control Appliance Modules
And then use the X-10 Arduino library to control each remote individually.
Or all at once.
  1. This means an Arduino can
  2. An hour before your morning rise time start a bread machine
  3. Followed by heating  your coffee ten minutes before
  4. Turn on your favorite morning program
  5. And gradually raise the lights

5 years ago

A relay is a better option than a triac for your first foray into electronics. What kind of things are you switching ? If they have motors in them, then a relay with contacts rated at 10X the running current is appropriate.

Josehf Murchison

5 years ago

I would use a BT137-500E triac or a MAC12D controlled with a BRT11H Phototriac Optocoupler.