How to dim a ceramic heat lamp?

Discussion in 'The Projects Forum' started by Plecc, Jan 11, 2012.

  1. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    Hello all,

    My friend has asked me to build him something called a sugar lamp, its a basic piece of kit with a stainless steel base and one or two 500-2000w ceramic heat lamps mounted above.

    This is the style of bulb required-
    http://www.alibaba.com/product-gs/216896842/Quartz_Ceramic_Emitter_Heater_Lamp/showimage.html

    The practical side of the build i am more than happy with, but i don't real have the experience to confidently tackle the electronic side.

    I need to make the lamps dimmable, so he can fine tune the temp.
    But i cant imagine its as simple a just using a heavy duty potentiometer. or is it?

    Thx,
    Dan.
     
  2. joeyd999

    AAC Fanatic!

    Jun 6, 2011
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    I assume these are running off AC? A Triac dimmer would work.
     
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  3. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    Thx for the quick reply,

    yep its a/c power.
    found some cool looking slider ones with a small led display!
    sorry to be a pest, but what does a triac dimmer do differently to a standard house hold dimmer?
     
  4. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    A "home" dimmer typically uses a triac.. but you can build your own dimmers using a triac circuit too.

    Just watch the wattage rating if using a home dimmer.
     
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  5. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    I just found a site that explains all the details, it looks like it works a bit like pwm.

    I think i will play it safe and go with an off the shelf one, do u think i will struggle to find one capable of handling the high wattage?
     
  6. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    Another thing you can do is a simple switch, to turn on one, two, or three of the elements, rather than the amount of power going to all three.

    There are rotary switches that do this, though they aren't easy to find.

    Most "light switch" dimmers have a 500W max capacity, so you'll need to build one that can handle 2kW.
     
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  7. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You can find regular dimmers in a range of wattage ratings.. But the cost goes up quickly.. I like thatoneguy's approach to using multiple elements and turning on more or less as needed if it works for you.. You don't get nearly as much control but you can get close with the right combination of elements.
     
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  8. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    Thx everyone,

    that sounds like a really good idea, just run 3 smaller lamps 250-500w all individually switched or dimmed.
    all the switch gear is so much cheaper in this range.

    Is it OK to run a 500w lamp on a 500w switch or dimmer? or is it wise for the switch to have a higher rating than the load?
     
  9. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    It's usually best to overrate components by 10 or 20%, especially when failure could result in fire. Make sure you are using a non-flammable enclosure, and try to find 750W dimmers if the elements are 500W-600W
     
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  10. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    Thank you,

    the whole thing will be made from stainless so no fire risk, but as its conductive is it important to ground the chassis?
     
  11. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    For safety reasons, the chassis is usually ground, the green or bare wire in the US. Not Neutral (white wire in US)
     
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  12. Plecc

    Thread Starter New Member

    Aug 26, 2010
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    Thought so, thats great!

    Thx allot.
     
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