Gradual On/Off Dimmer

Discussion in 'The Projects Forum' started by TerenceH, Jul 4, 2011.

  1. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    Hi,

    I am attempting to set up LED lighting for my fish tank. I would like for this to be on a slow on and off type to simulate sunrise and sunset. I have purchased GU10 sockets which will hold dimmable LEDs. I found two devices that are close to what I want but I am not sure if they will work in this application.

    I do not think this will work as it is 230V and I need 110V. http://fadisel.com/docs/R-11_English-Esp.pdf

    This one has to be assembled (soldering) which I do not have the confidence that I could do this correctly. http://www.velleman.eu/downloads/0/manual_k2657.pdf

    There will be roughly 25 lamps in this setup. I am thinking of running 5 to each cord and plug (not sure if that is the correct terminology). I am doing this so all lights are not at full brightness at the same time.

    I am a total beginner at this so please be patient with me as I may ask the same question repeatedly to help get a better understanding.
     
  2. #12

    Expert

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    The fadisel link says the manufacturer will provide the correct materials for 110 volt operation.

    It would be helpful if you told the wattage of the LEDs.
     
  3. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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  4. #12

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    Oops. It says, "will be provided with modifications" (not materials). That means no soldering.
     
  5. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    Thank you I did not see that. Also, it requires a minimum load of 50watts. My entire load will not be 50watts and they will be broken down into banks of 5 or so. Do you a suggestion for an alternative?
     
  6. #12

    Expert

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    Your entire load is 30 watts (25 lamps times 1.2 watts), so you can waste some power by adding anything that uses at least 20 watts. A 25 watt light bulb?

    Strange problem. Lights so efficient that you have to waste power to get them to work!
     
  7. iONic

    AAC Fanatic!

    Nov 16, 2007
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    All LED's are dimmable. This is done by varying the current through them. A simple PWM 555 circuit can do this, but it requires manual labor. Ideally you need a micro controller to really make this fully automatic.
     
  8. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    I would have to waste more than that as they will not all be on a single circuit (hope using the right word here). I want to put them in sets of 5 and move the lighting across the tank just as sun would. Any other suggestions?

    Microcontroller? Please explain! Go slow I am in first grade when it comes to this. :)
     
  9. #12

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    Do you think that the lights will not use power if they are connected to the controller with different cords? Are you using several controllers?

    If all the lights are not connected to a single controller, you should make that clear.
     
  10. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    That is what I was wondering. They will be connected on different cords. Would I need to use multiple controllers or would I only need one? Does each string of lights need its own controller?
     
  11. iONic

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    Perhaps I am entering 2nd grade with respect to micro controllers and am thus not the best to explain the details. The micro controller can create the PWM to vary the current to the LED's, thus slowly turning one string of LED's on, starting the second string as the first one fades out and so on. The micro controller can also do this to every day at the same time of day...etc. If the strings of LED's are spaced apart over the tank in a semicircle you could simulate the movement of the sun during the course of a day. A single micro controller can control all 6 strings of LED's.
     
  12. SgtWookie

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    Jul 17, 2007
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    iONic,
    The lamps our OP wants to use operate directly off of 110/120vac. You cannot use PWM on such lamps.
     
  13. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    What is PWM? Microcontroller it is then!!! Where do I get one these? Is there some sort of software used to make it work? I follow directions well.
     
  14. SgtWookie

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    TerenceH,
    It won't work for your project. iONic probably didn't understand that you are working with lamps that operate from mains power.

    I don't know how those lamps operate; how they are wired internally. They may or may not work with dimmers designed for incandescent lamps.
     
  15. iONic

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    ...never was the best at reading comprehension! Missed it. Thanks for the heads-up.

    He did start off discussing LED's, guess I dropped the ball after that. But 25 lamps must be really power consuming.
    I'd consider the switch to the LED's, but the OP would have to learn some programming.
     
  16. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    SgtWookie,

    They are "dimmable" LEDs. They work with incandescent dimmers. I included a link for them a while back.

    I guess we are back at the start of where do I go from here? How do I solve my wattage issue? Is there an alternate to what I suggested?
     
  17. SgtWookie

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    Well, you can buy dimmers at any hardware store in the electrical section - even Big Orange and Big Blue carry them.
     
  18. #12

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    Going back to post #10
    please excuse the detour.

    One controller will operate all 30 watts of lights, no matter how many cords you plug in to do the job. The controller will also want at least 50 watts of load. I have explained (in post #6) that you will need to waste 20 watts to get up to the minimum required by the controller. How you do that is up to you.

    You may ask again if I have not explained this well. After 40 years doing this, it is difficult to think on the first grade level. So many things we assume everybody knows, habits and such as that.

    Microcontrollers are not for first graders. Please excuse the detour.
     
  19. TerenceH

    Thread Starter New Member

    Jul 4, 2011
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    That is understood. How would I accomplish the slow on and off effect with those dimmers? Simulate sunrise and sunset?
     
  20. #12

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    The manufacturer has not been so convenient as to tell what the "switch" controls when you move the switch to the day or night position. It could be anything from a few milliamps to the whole 110 volt power voltage. You will either have to contact the manufacturer or buy one and measure its signal on the terminals for switching the mode of operation.
     
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