Connect with us

Auto NIght Light

Discussion in 'LEDs and Optoelectronics' started by durkmusic, Mar 8, 2012.

Scroll to continue with content
  1. durkmusic


    Oct 9, 2011
    I'm trying to build a night light which automatically turns on when it's dark and off when it's bright. I can figure out the circuit it's just one thing I'm missing and have been missing for a while.

    Problems: I can't figure out how to control an AC load with a DC signal. Basically, I want a certain voltage to be either on or off. When the voltage is on, the ac current will pass through the bulb and the light will be on. When there is no voltage, the bulb circuit will be open and the light will be off. I've searched relays, triacs, etc. I can't find anything that works besides relays! Maybe I'm missing something here. I don't really want to use relays so I'm trying to find an alternative.

  2. duke37


    Jan 9, 2011
    The relay is a good choice here since it can isolate the mains supply from the low voltage DC supply.
    You can use a triac but the DC supply will be live and needs good isolation from ground or human.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day