wheelro Posted June 1, 2004 Report Share Posted June 1, 2004 I have a 6 VDC power supply that I would like to use for some LED's.They are for a moonlight effect for an aquarium.I have 150 ohm resistors, the LED's are 3.5 V.How do I calculate if I have adequate resistance and or how many I can have inine?Thanks Quote Link to comment Share on other sites More sharing options...
ante Posted June 1, 2004 Report Share Posted June 1, 2004 wheelro,Welcome to this community!How much current are the LEDs rated for?Ante ::) Quote Link to comment Share on other sites More sharing options...
wheelro Posted June 1, 2004 Author Report Share Posted June 1, 2004 Thanks for the welcome....the package says 3.5V 5000 lumens.That's all the info I have.Does this help? Quote Link to comment Share on other sites More sharing options...
ante Posted June 1, 2004 Report Share Posted June 1, 2004 No not really, we need to know the maximum current allowed through the LED.Ante ::) Quote Link to comment Share on other sites More sharing options...
wheelro Posted June 1, 2004 Author Report Share Posted June 1, 2004 DC forward current: 30 mAPeak Pulse Forward Current 100 mAAvg. Forward Current 10 mAThanks Quote Link to comment Share on other sites More sharing options...
ante Posted June 2, 2004 Report Share Posted June 2, 2004 wheelro,If your PSU is 6VDC it will be fine with 150ohm in series whit each LED. Ante ::) Quote Link to comment Share on other sites More sharing options...
audioguru Posted June 2, 2004 Report Share Posted June 2, 2004 Wheelro,Your LEDs are "cool blue" aren't they? ;DYou can't use them "inline" (in series) because your 6V power supply doesn't have enough voltage. Using Ante's 150 ohm resistor in series with each puts 16.7mA through each one. Simply divide the current rating of the power supply by 16.7mA to calculate how many LEDs/resistors that it can power. ::) Quote Link to comment Share on other sites More sharing options...
ante Posted June 2, 2004 Report Share Posted June 2, 2004 audioguru,Thats why "150ohm in series whit [glow=red,2,300]each[/glow] LED.Ante ::) Quote Link to comment Share on other sites More sharing options...
audioguru Posted June 2, 2004 Report Share Posted June 2, 2004 Ante,Of course, I know, but I'm just making certain that Wheelro doesn't put them all "inline" like: LED, resistor, another LED, another resistor, etc., all in series. Quote Link to comment Share on other sites More sharing options...
ante Posted June 2, 2004 Report Share Posted June 2, 2004 audioguru,OK,They wouldn Quote Link to comment Share on other sites More sharing options...
audioguru Posted June 2, 2004 Report Share Posted June 2, 2004 Ante,Only if you heat them to a very high temperature with a blow-torch! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.