Looking for 3+Vin 120V 5A load Optocoupler?

Discussion in 'The Projects Forum' started by newt, Nov 17, 2009.

  1. newt

    Thread Starter New Member

    Jul 6, 2009
    Does anyone know where I can get and optocoupler that meets these characteristics:

    Normally Open
    3V input(trying to drive with microcontroller)
    120V 5A Load

    I have found this one: http://magnecraft.thomasnet.com/ite...?&plpver=10&origin=compare&filter=0&CTypeID=2 but it's $15!:( Anyone know of a cheaper option? Kudos if you find a multi-channel one meeting these specs.:D If it was multi-channel I wouldn't mind if it was a little pricey. Thanks all.
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    That is properly a solid state relay (SSR). With an output of only 3 volts, you might find it cheaper to use a Darlington driver to pull in a relay rated for the load.
  3. BMorse

    AAC Fanatic!

    Sep 26, 2009

    Check out http://www.digikey.com they have plenty of optocouplers with SCR outputs with Zero crossing that might suit your needs... they also have some where there are "multi channel"

    My .02
  4. newt

    Thread Starter New Member

    Jul 6, 2009
    Thanks BMorse. I think I found this one that should work for my application: D2W203F-11 I had to settle for 3.5A but that is fine.

    I plan on using this to control an outlet with my microcontroller. If I have a light plugged into the outlet and I want to dim it. Can I just turn the relay on and off at a certain frequency to create this behavior or could this cause issues(burn out lightbulb, spark on relay, etc.)? Is there a better possible approach? Thanks for your help!
  5. SgtWookie


    Jul 17, 2007
    Ack! :eek:

    No, that would be a very worn-out relay, very quickly.

    You're very new here, and we have no idea of what your experience level is with electricity and electronics.

    While the general focus of the Board is electricity and electronics, and related subjects, there is an overriding directive regarding safety issues.

    We like for our "newbies" to stick with low voltage projects (under 45v) until they have a good amount of experience. With low voltage projects, about the worst that can happen is burned fingers from hot components or soldering irons.

    When you eventually start working with mains power directly, safety becomes of critical importance. You can very easily be seriously injured or killed when working with mains power. Also, if sub-standard components or assembly methods are used, or ignoring proper grounding/shielding, the results could be a catastrophic fire or others injured or killed.

    Please refrain from experimenting with mains power directly until you have acquired a good deal more knowledge on the subject.

    I encourage you to instead explore the world of LEDs; they operate at low voltage and current levels, and are very easy to control using a uC.
  6. newt

    Thread Starter New Member

    Jul 6, 2009
    I understand what you are saying, and safety is the only reason I posted the question. My experience so far has been 90% low voltage. I'm a junior with a computer engineering major. I have made it to the point where I want to expand into higher voltage applications. In low voltage and digital I would have solved this problem as I described. I wasn't sure how to tackle this challenge with high voltage though, and I knew this would not be good on a regular relay, but I wasn't sure on an opto-coupled ssr? If this will wear out the relay as you say, do you have a suggestion for a solution to this problem? Thanks for your reply.