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Unread 03/30/2009, 05:36 PM   #576
kcress
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Join Date: Dec 2007
Location: Central California Coast.
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Quote:
Originally posted by ReefEnabler
Stu thanks for posting that reminder.

Most of my LEDs are 1000ma rated and I'm using 700ma pucks.

But I was planning to mix a Cyan LED in one of the arrays, its rated at 700ma max.

Could I just position it at the end of a series and put a resister before it to step it down?
Negative, negative, negative!!

The same current runs thru all of the elements in a series chain.


But! You can achieve what you want by shunting the LED of your choice with a resistor so some of the current runs around your LED. Since properly sized and mounted resistors don't fail this is a safe 'paralleling'.

Tell me the expected VF for the LED you want toned down and the current you will be running and I can tell you what resistor you'll want. (Better would be the actual VF, of the actual LED, at the actual current.)


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