Lighting 39V 2.1A COBs good/cheapish drivers?

[BigSm0]

Bump ! @BigSm0

Guys if something comes up and I overlook it or you need a quick answer just @me. I seem to get those lol. Some days I wake to 50-100 alerts so it's easy to overlook too. I hate to keep anyone waiting.

 

[Rapha El]

holy shit have you guys seen this one?!

http://www.digikey.de/product-detai...C30-F4-3/CXM-32-40-70-54-AC30-F4-3-ND/6151721
look at the efficiency, price and max output. I think i have a new favourite

just did some rough maths in my head.. that's 1.8times as efficient as an hps. take two of those at 220watts and you (hlg/evg 240) and you can get about the same light output as a 400watt hps

 

[Rapha El]

For the sake of efficiency I took it down from 2.8a to 2.1 and have to say.. it's quite nice

40k lumens at 240 watts (400 watt hps does about 55k) and still a little room left for step down converters for the fans.
Change the fan driver to 2x500ma and it fits

I did the comparisons and they are the most efficient cob I've come across so far.

V ma watt lumen price lm/E lm/W
51 3750 191,25 34632 33,67 € 1029 181
51 3250 165,75 30303 33,67 € 900 183
51 2800 142,80 26.507 33,67 € 787 186
51 2250 114,75 21645 33,67 € 643 189
51 2100 107,10 20302 33,67 € 603 190
51 1750 089,25 17158 33,67 € 510 192
51 1400 071,40 13903 33,67 € 413 195
51 1250 063,75 12771 33,67 € 379 200
51 750 038,25 08008 33,67 € 238 209

The problem is finding holders that fit this thing.. I came up empty. If anyone knows of some please let me know. Otherwise I'll have to use thermal gue

 

[pop22]

good luck with these! You'll be a pioneer. Get us real world data when you build a light.

For the sake of efficiency I took it down from 2.8a to 2.1 and have to say.. it's quite nice

View attachment 663530

40k lumens at 240 watts (400 watt hps does about 55k) and still a little room left for step down converters for the fans.
Change the fan driver to 2x500ma and it fits

I did the comparisons and they are the most efficient cob I've come across so far.

V ma watt lumen price lm/E lm/W
51 3750 191,25 34632 33,67 € 1029 181
51 3250 165,75 30303 33,67 € 900 183
51 2800 142,80 26.507 33,67 € 787 186
51 2250 114,75 21645 33,67 € 643 189
51 2100 107,10 20302 33,67 € 603 190
51 1750 089,25 17158 33,67 € 510 192
51 1400 071,40 13903 33,67 € 413 195
51 1250 063,75 12771 33,67 € 379 200
51 750 038,25 08008 33,67 € 238 209

The problem is finding holders that fit this thing.. I came up empty. If anyone knows of some please let me know. Otherwise I'll have to use thermal gue

 

[Rapha El]

Aaalrighty just to test things out with cobs I went with a little setup for supplementing my current light.

~120w total

1x hlg 120h c1050
4x citi 038 1206
some massive pc tower style coolers off of an old server
thermal glue
random assortment of wires

That should give me 10 to 17k lumens depending on dimming. 153lm/w at best 138lm/w at max output.
All the stuff should arrive in around two weeks.. I'm excited to see how it works out.

 

[BigSm0]

How much were the cobs and where did you get them? How do they compare to the less expensive 1212's. Options are always nice

 

[Rapha El]

They were 6 bucks a pop in a 5-pack from that estonian ebay guy. They are pretty much half a 1212. Literally.
Looking at the spec sheets, the relative efficiencies are the same. Just half of what a 1212 would get you. But they(and the driver for em) are cheap so for a test of COBs in general and citi in specific I'd say they are a good pick.

Oh have you seen the new hlg 480 c series? Holy hell those things can put out some power.

 

[pop22]

The problem with spec sheets is they are often not all that accurate. Current gen Citi chips are 7%+ more efficient than those chips. Doesn't make them bad, just not as much of a bargin as they seems. How much PAR difference will there be at +5-7% times 4 chips? x8? etc.

One thing we don't have here yet... on AFN is extensive data collected and posted in charts and graphs. RIU is good for that. It shows that some chips exceed they manufacturers specs a fair amount. Some don't.

But those chips as I said are good, and FAR better than any of the Chinese junk you'll find on ebay!

They were 6 bucks a pop in a 5-pack from that estonian ebay guy. They are pretty much half a 1212. Literally.
Looking at the spec sheets, the relative efficiencies are the same. Just half of what a 1212 would get you. But they(and the driver for em) are cheap so for a test of COBs in general and citi in specific I'd say they are a good pick.

Oh have you seen the new hlg 480 c series? Holy hell those things can put out some power.

 

[BigSm0]

The problem with spec sheets is they are often not all that accurate. Current gen Citi chips are 7%+ more efficient than those chips. Doesn't make them bad, just not as much of a bargin as they seems. How much PAR difference will there be at +5-7% times 4 chips? x8? etc.

One thing we don't have here yet... on AFN is extensive data collected and posted in charts and graphs. RIU is good for that. It shows that some chips exceed they manufacturers specs a fair amount. Some don't.

But those chips as I said are good, and FAR better than any of the Chinese junk you'll find on ebay!

I got into 2 little disputes here. Now me and the guy are tight. @Fairlynew id consider him a friend now. The charts you mentioned come from the worst devil cult mafia gang whatever you want to call those clowns. I'd rather see people ask questions to one of us than see anyone head there. Or maybe we can rearrange them so it's not like we directly stole data and reposted it.

 

[pop22]

I've asked for permission to post data collected by Cobkits and he was all for it, said I could use any of his stuff. The dude is good in my book. He's not one of the Know-it-all gang. He's also collected good data, and he and Northern Growlights guys seem to be tight. I'll gather what I can from them. I'm also downloading a ton of data sheets on COBS and needed parts. I'll be making some posts when I have what I want.

As for what I have borrowed, info posted on public forum is not copyright material. When you post of a public forum, any information in it, not currently under copyright is considered public domain by law.

Now if someone would just buy me some test equipment I'll do it myself, should only cost about $40,000 for everything...........lol!

I got into 2 little disputes here. Now me and the guy are tight. @Fairlynew id consider him a friend now. The charts you mentioned come from the worst devil cult mafia gang whatever you want to call those clowns. I'd rather see people ask questions to one of us than see anyone head there. Or maybe we can rearrange them so it's not like we directly stole data and reposted it.