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CobKits

Well-Known Member
SOB

Does this sound about right everyone? I guess I do need the 54B or 48A?
yup.

48Bs are only good for a ton of 50V chips at low current. so you could actually throw all those chips on one driver and it would be 180W. cxm22s are a little high voltage for this application unless you want to run them at 20W or so, you could push some 1825s and some vero Bs pretty far at 48V tho.

if you need external dimming the 54B is the only option. The downside of the 54B is that the 54 series has less current available than the 48 series. thats where 48A wins in bang for the buck with these chips, youre guaranteed a full 225W on the DC side with most arrangements
 

kaivorth

Active Member
Adding a 5 volt power supply in series should work. I'll see what i can find...
I would give one of these a try, a lot cheaper than new drivers. It gets you up to 53 volts and the HLG-185-48B will still control voltage/current.
http://www.ebay.com/itm/Arndt-EADP-20NB-5-Volt-4-Amp-20-Watt-Regulated-Table-Top-Power-Supply-/122309563350?hash=item1c7a37d3d6:g:WS8AAOSw-0xYeJ0E
http://www.ebay.com/itm/Mean-Well-RS-15-5-Enclosed-Switching-5-Volt-3-Amp-AC-DC-Power-Supply-5V-3A-15W-/112158655353?hash=item1a1d2d4379:g:TwgAAOSwJ7RYUaOm.

This is a little cheaper option, the drivers could share a common negative with this in series.
http://www.ebay.com/itm/Mean-Well-RS-50-5-AC-to-DC-Power-Supply-Single-Output-5-Volt-10-Amp-50-Watt-/122214375437?hash=item1c748b600d:g:ACEAAOSwHMJYH3kD
Any advantages of one meanwell vs the other? Appreciate the help.
 

1212ham

Well-Known Member
The first one is rated at 5 amps so you would need two, one in series with each driver. The second is rated 10 amps, only one needed.
 

kaivorth

Active Member
The first one is rated at 5 amps so you would need two, one in series with each driver. The second is rated 10 amps, only one needed.
I wish I was more knowledgeable with this stuff. I'm going to order the 2nd one
http://www.ebay.com/itm/Mean-Well-RS-50-5-AC-to-DC-Power-Supply-Single-Output-5-Volt-10-Amp-50-Watt-/122214375437?hash=item1c748b600d:g:ACEAAOSwHMJYH3kD

Hope this fixes everything. So am I hooking this up in series or parallel with my current drivers?
 

1212ham

Well-Known Member
Post #2386. ;) The 5v supply needs to connect in series with the driver. Since you have two drivers, connect negative of both drivers to positive of the 5v supply. Now connect two wires to negative of the 5v supply and use these as if they are the negative wires from the drivers. Thank God I understand this stuff better than I can explain it!
 

CobKits

Well-Known Member
we lost a legend tonight :(

RIP Col. Bruce. Laid down and died onstage near the end of the encore of his epic 4 hour 70th birthday bash. Thats as rock and roll as it gets

 

SPARC

Member
@CobKits you mentioned a few pages back that you would not be stocking the 1818 in the future due to it having similiar performance to the CXM22. Is this still the plan considering the citi gen 6 have more performance?

I like to run the 1818 around 90w instead of the 75w sweet spot for the CXM, and I like dealing with you directly so I hope you continue to carry them, at least until the CXM catches up around 85-100w.
 

gazza2005au

Active Member
Hey Cobkits

I have a Secret Jardin L90 Lodge im going to run 4x cree cxb3590 in the flowering side but what passive leds would u recommend for my pre veg section, i plan on vegging to around 10-12" my veg chamber is 24x12" height is not an issue

Thanks
 

CobKits

Well-Known Member
@CobKits you mentioned a few pages back that you would not be stocking the 1818 in the future due to it having similiar performance to the CXM22.
people keep buying them and i can get them in 30 pk so i will prob keep stocking

Is this still the plan considering the citi gen 6 have more performance?
im not so sure of that, theyre probably pretty close in performance

I like to run the 1818 around 90w instead of the 75w sweet spot for the CXM, and I like dealing with you directly so I hope you continue to carry them, at least until the CXM catches up around 85-100w.
hard to say what will be on the leaderboard in 6 months, things move so fast!
 

SPARC

Member
im not so sure of that, theyre probably pretty close in performance
Thanks for the reply. Do you have any efficiency or QER numbers on the CXM22? I found a thread here where you had a citizen chart for the gen5 that listed the 1818 at 55% for 1.8A. Are these numbers close to the CXM22 at 90w or so?

Thanks again
 

CobKits

Well-Known Member
i dont think anyone has calced QER for gen 6, the spectrum is slightly different.

i dont meddle in the absolute efficiency numbers too much as there are so many variables to try to reach an exact number

side by side CXM22 beats any chip in can find under $30 across the board (including the $35 CXB), and hangs with just about any chip out there regardless of price up to 75W or so.

above 75W the more expensive chips like Vero29C, citi 1825/3618, luminus CXM32 will pull away. (and then at 100W were talking 5% efficiency gain at twice the chip price or more)

Few people operate their cobs so hot when a $17 chip can get you out to 75W with top-shelf efficiency. Again i dont push them because i stock them, i stock them because theyre the best COB value going right now
 
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CobKits

Well-Known Member
ill run 1818 gen 6 vs cxm22 in my testing rig today. i need to come up with a new name for it becuase GG melted down for me calling it a "sphere test" without being NIST-calibrated method.

like most of you guys, i just want to know relative PAR output per W of energy input for a similar spectrum. if you really want to dive into the complexity of light measurement science, have at it:

https://www.labsphere.com/site/assets/files/2551/a-guide-to-integrating-sphere-theory-and-applications.pdf

im happy enough to get repeatable results that are useful for my purposes
 

CobKits

Well-Known Member
heads up: this knockoff site is not affiliated with Cobkits at all, despite using the name

http://cobkits.co.uk

looks pretty scammy, tbh. apart from the sleazy name-ripoff, a lot of their product offerings don't even make sense, and there is not a lick of contact information for this fly-by-night shop. dont get scammed! We do ship to the UK, but from our US-based operation
 
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