LED PS differences

Discussion in 'General Electronics Chat' started by jjanes, Aug 25, 2013.

  1. jjanes

    Thread Starter New Member

    Aug 2, 2010
    What exactly is an LED power supply compared to a standard power supply.

    I am looking for a 12V 500W power supply not for a computer and I see several that show those specs but some throw in the term LED also
    Some examples

    Switching Power Supply 12V40A (500W) Industrial Power Supply CE ROHS
    12V DC 40A 500W LED DC Regulated Switching Power Supply
    12V DC 40A 500W Regulated Switching Power Supply
    500W 12V dc switching power supply
    500W LED Switching Power Supply, 12V
    12V40A 480W AC-DCsurveillance cameras/LED light switching power supply

    Some vary in price considerably and I can't find out what the real difference is. I will be powering a few LEDs but they wont be the heart of the project. It will be the power supply for a 3d printer. I found one but it was an LED type and I am not sure if it would work.

    I have heard two differing views one to stay away the LED types and one saying it will work just like any other power supply. but in both case they gave the opinion but without any real reasoning behind it and with no breakdown as to what the differences actually are. I would like to go ahead and get one but I want to make sure I am getting something that will work.

    So thanks to anyone who can get me straightened out about this
    oh and any other things to look for or stay away from would be appreciated as well ;):D;)
  2. Shagas

    Active Member

    May 13, 2013
    I've never used a dedicated LEd power supply but I think the diffrence is that they provide a constant current output instead of a constant adjustable or fixed voltage.
    jjanes likes this.
  3. wayneh


    Sep 9, 2010
    Not good. You want a constant voltage supply. The amount of current varies with the load, and you need a supply rated to at least as much as the load requires. Adding 50% or more is a good idea. A constant voltage supply is a more typical power supply, for instance it is what you would find in a computer or in just about everything else in your house that has a power supply.

    The "LED" power supply is just a constant current supply. The voltage can swing over a wide range as the supply tries to maintain a constant current. That's perfect for LEDs but not a lot else. An LED power supply might be different from other constant current supplies because it may also use PWM to allow adjusting the current level.

    Both types of supply may be adjustable, but in one case you are adjusting voltage and in the other, current.
    jjanes likes this.
  4. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    Putting the term "LED" into a power supply description "should" mean its a constant current power supply.
    However... the Chinese have screwed that up on ebay and many..many times a power supply with the word "LED" in the description is just a regular constant voltage power supply. The just throw led in there to get more keywords..
    jjanes and #12 like this.
  5. MrChips


    Oct 2, 2009
    LED power supplies are usually constant current sources. However you can get either constant current or constant voltage LED supplies.

    If an LED power supply sells for considerably less that a regular power supply, ask yourself why.

    An LED supply does not need the regulation, stability, low noise and low ripple as a regular supply. If you don't need all of those then go for it.

    Note also LED power supplies should have on-surge suppression.
    jjanes likes this.