Powering My New LED 10-Volt 10-watt R.V. Lights

How many lumens does each chip produce?

Some of these are suprizingly quiet. I have the smaller version powering Ledzilla and its dead quiet. Dont know anything about this one tho..

SCFJeff,
That is one wonderful bucker. I have maybe eight of them. Musing things over I might have to install buckers maybe more than one on the fuse panel feeder circuit then run feed lines through homemade PI filters. I am sort of hoping to take up Shortwave as a hobby and I sort of suspect I has better start planning to reduce radio frequency emissions now rather than get clobbered after I switch the set on. Because the house is already overwhelmed with gear the hobby will have to take place in the rig. Shortwave is quite a chunk to bite off at my age but what the heck-never too old to learn. The tallest parota is maybe 30 meters and Chango is savvy enough to haul the antenna up the tree and drive lag screws.

How about THIS. Plenny o' head room.

I removed some fluorescent lighting from kitchens whose residents were legally blind. They still have some vision.

I replaced them with LED cans bought from HomeDepot. Both ladies remarked how much better they could see with the LED lighting.

Unfortunately some of these LEDs are failing 8 or 10 years later. Most likely the drivers burnt out rather than the LEDs themselves.

i think maybe they do
but i am also sure the light is a different color wave length than white LED

I just did not have the heart to say anything. Can you imagine the heat at a consumption value of double the wattage VA at 12-volts? The specs did not mention laying out the new chips for constant current but I'll try it and see if it can be done like a 37. At present I am in a house reading under a 36 volt fan cooled 30 -watt chip. Battery + converter and DC to DC booster. It might be my imagination but it seems my eyes get far less tired with LED lighting as compared to CFL lighting. Do CFL's flicker too fast to detect?

Gdetrailer wrote:

Wrong.

You need to understand just HOW these LEDs are wired..

I have one of these same LED modules that Mex has so I am very aware of the design and not to mention I have MEASURED current draw of said modules..

These modules are known as COB or chip on board. They are an array of 1W LEDs mounted on a plate.

There is three parallel ROWs of LEDs, each row has THREE WHITE LEDS in series..

Each white LED requires 3.4V to light so each ROW requires about 10.2 V..

Each ROW only consumes about 1W since LEDs in series share the same amount of wattage like a resistor in series)

Each row is 1/3 of the current draw (and wattage) but all the LUMENS are added together..

So technically all three parallel ROWs added together will draw about 3W at 10V if you really wish to be accurate..

The manufacturers kind of skew the actual wattage drawn since they add up the wattage of all the chips on the board.. Technically it is a 9W module but they round it up to 10W for marketing purposes.. But in reality it is drawing not much more than 3W at 10V..

Wattage (for a DC circuit) is defined as voltage times current. Each of the LEDs in a chain does of course see the same current, but since the voltage across the three LEDs is three times the voltage across a single LED, the power is also three times as great.

If you power nine 1W LEDs to full brightness, they are consuming 9W of power, regardless of whether they're wired in parallel (about 2.6A at 3.4V) or in series (0.26A at about 34V) or in some other manner (maybe 0.88A at 10.2V).

Resistors in series also behave the same way at a given voltage and current. (Resistors do, of course, exhibit different behavior than LEDs in relation to changing voltages.) A resistor that dissipates 1W of power, if put in series with other resistors with the voltage increased such that the current remains the same, will still dissipate its 1W of power while its companions also dissipate additional power. Likewise, If you connect two 1500W 120VAC heaters in series (they're essentially resistors, after all), and then connect the whole to a 240VAC circuit, the heaters consume a total of 3000W and put out 3000W of heat.

Each ROW only consumes about 1W since LEDs in series share the same amount of wattage like a resistor in series

If each LED is 1 watt, the total is 9 watts, Not 3 watts
Current is the same and not added in series but the voltage is increased and the wattage is totaled for each string then added together for the board
Resistance in series is added so is wattage, resistance in parallel is reduced

I "have to have" a rational reason for making a seeming simple job complex.

My bad eyes need more lighting than normal. In the galley, over the dinette, and a bedroom reading light I would like to have pair of those chips in each fixture. Above each goes a micro fan. But it looks like I am going to have to use those 7.5 amp rated regulators. Their efficiency is supposed to be an extreme improvement over the LM fixed. The new chips use a circuit layout similar to the 317. Near the dropout point the new regs are supposed to be 90% more efficient. But they do need a board. An LED driver circuit will not fit if I am going to incorporate a micro fan. I was tring to "cheat the system" and close my eyes to the spec sheet and ask and hope for the best. I really dislike designing purely by E=MC2 I would rather regulate those chips by visual lumen output versus chip temperature/time rise rate. With a max of 50c on the chip. Next week promises to be interesting. With that PS unit (I have a military Lambda two thousand miles away)I will be able to easily "proof" chips. The key is temperature. And why in god's name don't these buzzards black anodize those component heat sinks? And if anyone has a source for LED drivers the size of three postage stamps laid end-to-end please clue me in.