Deleted
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Post by Deleted on Aug 21, 2013 6:24:55 GMT
A word of warning. Please check the DC voltage out before using them. Yesterday I made up a plugpack supplied Die Cast aluminium box with 3 x 3W Warm White Cree LEDs on the front for lighting purposes.. The idea was to power this from a 15V 1A SMPS plugpack originally designed to be used with an Optus Broadband modem. Luckily, I included a 1W 1ohm resistor in series with the main 8.2ohm 5W series resistor in order to check the drawn current. Assuming around 3.5V DC across each of the 3 series LEDs, the simple series 8.2 ohm resistor should have had around 4.5V across it for a current of approximately 550mA. I was surprised to see .7V across the 1 ohm resistor, which indicated a current draw of 700mA which is the rated maximum for these Cree LEDs. The supposedly 15V 1A SMPS plugpack was putting out 19Volts under load !!! I ended up using an additional 1.8 ohms PW5 resistor in series with the existing 8.2 ohms PW5 resistor. Yes, it is VERY bright! Alex
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