Resistor questions for Tri Cree B/B/W with NBv3

**SPACEMONKEY1** · 02-14-2016, 09:56 PM

Ok. So the larger the watts and ohm number of the resistor the less bright the led will be? That's where I was getting confused. Thought the 2w 1 ohm allowed more to the LED. So the original .5w 1.8ohm should be fine for all?

**NanoRex** · 02-14-2016, 10:50 PM

Ohms measure resistance. More resistance -> less current -> less brightness, so use the lowest amount of resistance that you can, provided that it's greater or equal to the amount you calculated.

Watts measure power. In the case of resistors, it's how much power the resistor can dissipate. Higher wattage -> can dissipate more power, and larger resistor. Using a higher wattage resistor won't affect the brightness of your LED at all, but it will take up more space in the hilt.

**Gorth** · 02-16-2016, 03:46 AM

Actually if you read the manual, any led that only needs a small resistor (<.5ohm) you can change the drive to the led from the board to less than 1Amp, so you can max out the possible current going to you leds

**Gorth** · 02-16-2016, 03:50 AM

You could also put small resistors in parallel or larger resistors in series. For example for your blue led, having two .5ohm resistors in parallel would give you .25 ohm resistance which is much closer to the number you need

**darth_chasm** · 02-16-2016, 04:16 AM

Originally Posted by Gorth

Actually if you read the manual, any led that only needs a small resistor (<.5ohm) you can change the drive to the led from the board to less than 1Amp, so you can max out the possible current going to you leds

I've done both ways and can confidently say that using resistors is the more reliable method. We're talking about .5 watt resistors, they're not going to take up that much room if that's the concern. If anything, buy the resistors so you have them as a back up. They're a few bucks at most and you won't have to go back, place another order and pay another shipping charge.

**SPACEMONKEY1** · 02-17-2016, 10:45 PM

Thanks for all the info with this everyone!!! Gonna try and find a .5 ohm 1.8 or 2 w resistor for the blues. And a 1 ohm .5 watt for the white FoC LED.

**SPACEMONKEY1** · 02-17-2016, 11:05 PM

One last question. Nano, you said I could probably use the .5 ohm resistor on the white as well? My calculation is telling me that I need a .55 ohm resistor at .5 watts. Would I be pushing it if I put this one on the white with it being .05 over the needed ohm resistance?