Connect with us

2-10v or 4-20 dimming of 120v light bulb

Discussion in 'LEDs and Optoelectronics' started by Scott McDonald, Dec 21, 2014.

Scroll to continue with content
  1. Scott McDonald

    Scott McDonald

    1
    0
    Dec 21, 2014
    Good morning, working on a project where I need to demonstrate a modulating temperature controller, using a 100w bulb as a heat source. I'm looking for device that will take a 2-10v or 4-20 mA signal from my controller and vary current to the bulb... Any ideas?

    Thanks!
     
  2. Arouse1973

    Arouse1973 Adam

    5,164
    1,087
    Dec 18, 2013
    What about an automatic light dimmer using an LED and LDR. The light dimmer circuit is fairly simple so instead of using a POT which you turn to increase the brightness you control the current through the LED. So when the irradiance on the LDR increases as the LED gets brighter then this changes the brightness of the bulb. In your application it would be the 2-10Volts which does this by increasing the current through the LED. And obviously works the other way also which would reduce the brightness as the input voltage fell.
    Adam
     
    Last edited: Dec 21, 2014
  3. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,271
    Nov 28, 2011
    Is the bulb running from AC or DC? What voltage?
     
  4. Arouse1973

    Arouse1973 Adam

    5,164
    1,087
    Dec 18, 2013
    I think it's 120V Kris, I am guessing A.C.
    Adam
     
  5. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,271
    Nov 28, 2011
    You know what happens when you ass-u-me :)
     
  6. Arouse1973

    Arouse1973 Adam

    5,164
    1,087
    Dec 18, 2013
    Yes I have been bitten many times :) But he does say 120V bulb in the title.
     
    KrisBlueNZ likes this.
  7. hevans1944

    hevans1944 Hop - AC8NS

    4,615
    2,154
    Jun 21, 2012
    Do you want to build something from components, or buy off-the-shelf? This company offers a wide variety of solutions, one example at this link.

    Please provide more specifications: Is this a 115 V AC 100 watt incandescent lamp you are using as a heater? How will you sense the temperature you intend to control? What range of temperatures? How much resolution and accuracy do you need for heater control? There are other considerations.
     
    KrisBlueNZ likes this.
  8. JWHassler

    JWHassler

    81
    17
    Dec 22, 2014

    Here's a pretty-good description of what's available.
    Are you doing your own current modulation scheme, or simply asking for a power-percentage?
     
    Last edited: Dec 22, 2014
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

-