Cob voltage?

is it better to run at a higher voltage and lower amperage?

man you start a lot of threads lol, j/k

1. for any given cob, the voltage is closely related to current and follows the curve given on the datasheet. so you dont really have the option of running a particular cob at high voltage/low current vs low voltage/high current

2. for cobs of a given series where multiple voltages are available, they can be the same number of dies and same layout (like cree cxb3590 in 36V and 72V). or they can be completely different chips (like Vero gen7 C vs D model). in the former case the chips will perform identically based on wattage (ie a 36V cxb @ 1400 mA acts identically to a 72V cxb@ 700 mA - both are about 48W and are equally bright, equally efficient, with the same heat load. in the latter case (vero), the C series has more dies and is more efficient at a given wattage - they are truly different chips

3. you can run chips as hard or soft as you want, and select another models if one doesnt operate well within your target range.
there are a bunch of reasons why you would choose to run one chip over another, or run a given chip harder or softer including: budget, electrical power cost, environment and hpw you deal with heat, budget, etc etc.

I have questions that I have not found answers to yet ok cool got that sorted out now how bout those cone reflectors do you need them? Should you use them? I will deal with heat passively.

In your opinion would it be better to step up to 50 volt or is 36 just fine for what I want to do?

voltage is a flexibility factor. If you have lower voltage COB's 30-40v you have a ranger of affordable led drivers for use. If you have a higher voltage 50v-75v you have a different range of led rivers that may cost more or less. The clue is to look at forward voltage Vf for the driver you are interested in using. Most of the lower current drivers C700B have higher Vf while higher rated current drivers C1400B have lower Vf. So with lower voltage cobs you can us up to 4 on a 200w driver. With higher voltage cob's you can use 2 on a 200w driver. Higher voltages means more drivers per cobs, while lower voltage means fewer drivers per cob. Cost economics. if you want to run even lower wattage per SF, lower voltage cob's are a necessity.

Ok so if I stick with 36v at 1.1 amp remains affordable will give me the light I need 1212 90cri 3000k be about 40 ish watts sf.

Manfromthenorth said:

Ok so if I stick with 36v at 1.1 amp remains affordable will give me the light I need 1212 90cri 3000k be about 40 ish watts sf.

Click to expand...

watts = volts x amps 36v x 1.1a = 39.6w I would consider 1400 for a full 50w vice the 1050 driver, just me tho. I would rather have to turn them down than wish I could turn them up..

Ok so would be looking at a 1400ma driver for 8 cobs with a dimming feature?