LEDgardener

Hey guys, been a while since I posted here about the various Shenzen "lm561c" boards from China and I'd thought I post what I have been up to. I recently was able to customize the spectrum of the 288 board, and came up with the outer 4 rows 3000K, middle 2 rows 2700K and a single row of 4000K in between the two warmer spectrums. I rec'd the boards yesterday and had heatsinks and drivers ready to go and about to list them on eBay.

I wanted to create a board that hasn't been made (at least in the 288pc design) and eventually seek to create my own products, free of any generic knockoff tag attached to it. Have big plans for a custom board with "newer" diodes that I think HLG will probably beat me too lol. Hopefully there is room for small fish like me within the giant market share that HLG currently maintains in the mid power game. Stay tuned..

I was also able to acquire integrated sphere data on the boards, but I think they did not list micromoles/ joule. Seems to be more a spectrum analysis and lumen/ watt, but would like some help making sense of it. I was told that one reading was of the max current, and one was of most efficient light output. I will post the data of both the mixed spectrum board, and the 3000K at the risk of being embarrassed if these are not true LM561c's. Anyways, here are the pics:

3 spectrum diodes close up 3000K left, 4000k center 2700K right

cool stuff, but 150/135 lm/w don't sound like lm561c to me, or am i wrong?

Data for 3000K boards Pic of mixed spectrum lit up and wattage full power (w/ HLG-120H-54B dimmer)

The lumens-per-watt could be the lm561c@CRI90, but since it wasn't specified (and those are harder to come by) I'm assuming that's not the case. Also, the spectrum would have shifted more to the right with CRI90. Looks like the sphere is showing the SMDs used on these PCBs are something else.

tazztone wrote: ↑

Thu Apr 26, 2018 11:07 am

cool stuff, but 150/135 lm/w don't sound like lm561c to me, or am i wrong?

Yeah, was wondering the same thing when I first saw it. It could be the 2700K diodes bringing the lm/w down but I would have to see it side by side with a HLG 288's sphere data to know. Judging by the looks, what other diode do you think they use? I know posting the data leaves me open to being torn to shreds, but I'm about transparency and knowing what I truly have. If anyone else has contrary/ supporting data on their 288 boards, please post to compare. These sphere tests are not done by me but the mfg. in case anyone is wondering.

The 2700K diodes have a lower LPW efficacy, but the 4000K ones balance them off the other end. On average, as the datasheet shows, the CCT rendering stays a bit over 3000K.

Assuming you ordered CRI of 80, Vf category AZ (27.7v) and top bin (S6) you should expect around 176LPW (factoring in 94% efficiency of the driver and the amperage they were driven at). Staying with LM561C but going down to the S4 bin already gives 156LPW. Assuming the chips are Samsung's you can play around and see what others fit: https://www.samsung.com/led/support/too ... alculator/

I'm really surprised at suppliers not understanding the value of a positive reputation. Pocketing the difference between a S4 bin and an S6 bin would be only tiny in comparison with building a trusting relationship with buyers interested buying in bulk. You, being transparent about this, are only earning credit for anybody who will be dealing with your boards.

Hey mate I made a account just to say they look awesome I was wondering if anyone made them.id rather buy from a honest smalller scale guy than China factory made lights. I wish someone in Australia sold pre assembled units with this spectrum and I wish I didn't just blow my medical budget on cobs for my stealth cupboard. Love your work all the way from Aus . A year ago I didn't smoke , spent the last 9 in and out of hospital beds except the last one when I decided to start smoking , severe disabling chronic pain , torretes , OCD, anxiety and severe depression I couldn't get out of bed I was on huge amounts of opiates and ketamine infusions life was hell now I smoke and everything has changed I study now and am looking to find work . Iv also been studying lighting because I wanted the best closet I could get on a slow dissability payment stream and I wish I had of know more about quantum boards before I got my light. What has your average yield per watt been like mate? absolutely loving your work . Keep it up. Cheers

Do you feel like sharing where you ordered the boards from, for future reference? If they are selling something else as lm561c's, its good to know to avoid them.

Mad respect for putting your neck out like this.

Like others have said, it's amazing how short sided these Chinese sellers are. But hey if their margins allow, demand will dictate.

How long was the whole process once you found your supplier? How many months?