Re: That 60W-equivalent LED: What you don't know, and what no one will tell you

Well the issue is heat in existing fixtures. As most are designed simply to be safe up to a particular wattage of incandescent with no ventilation as that would contribute to heat buildup in uncontrolled areas. Regular incandescents run at 4-500deg while LED lights are maxed at 185. The LED also still creates heat from 70%+ of the power consumed. The LED I have been working with is a 3x3 array of one watt illuminators. Pic provided. when being driven at 9w they are about 80-85% as bright as a fresh fully...

Re: That 60W-equivalent LED: What you don't know, and what no one will tell you

I have been experimenting with LEDs for the last month or so. First thing I discovered is they get VERY hot. I used the load shown in pic for some testing and at 5.6w the temperature at the base junction exceeded 254deg(124C). After much testing with linear constant current and constant voltage supplies I found they need precision voltage and current limiting for best efficiency. And, using a 10w array, I found that the drive voltage can be from 26 to 38v so unless you adjust the driver per Assy it's...

Re: LED POwer Consumption

Sounds like your driving a flasher chip which might run at much less power. Possible to get 30hr if you current limit it.

You can use a 100ma lm317 with a 62ohm resistor and feed constant current of 20ma for max battery life. Using as adjustable voltage you can measure the actual current and calculate a better resistor.

Resistor goes between Output and Adjust pins. Input from battery with output to LED from adjust pin. 0v connects directly to battery.

Fig 21 on Page 8 of the attached datasheet shows the wiring....

Re: resistor 5 band



It is always important if it's [COLOR="black"][B][U].25%[/U][/B][/COLOR] they don't spend $$ if it isn't needed. That being said, another consideration can be thermal coefficient. While you can make your own precision resistor you wouldn't be able to duplicate the thermal coef.Re: resistor 5 band



It is always important if it's [COLOR="black"][B][U].25%[/U][/B][/COLOR] they don't spend $$ if it isn't needed. That being said, another consideration can be thermal coefficient. While you can make your...

Re: Covering SMD LEDs with bluetac

Not unless they are so overdriven they would burn out anyway. Use a removable covering so you can change your mind.

Re: ESR and V tester

How does a low voltage tester certify<(?) a high voltage capacitor?