i’ll not buy another led until..

i’d be willing to pay 10-20% extra to cover the build and shipping costs of bigger heatsinks

  • yes

    Votes: 14 46.7%
  • no

    Votes: 16 53.3%

  • Total voters
    30

crimsonecho

Well-Known Member
..they make these bar type lights or whatever with properly overbuilt heatsinks. i recently watched a migro video where he evaluated different lights based on their par loss including his own and concluded that in 4 years they will be at 80% or something.

so you gotta change out your fixtures every 4 years if driving at 100% and heatsinks are getting above 40-45C. thats just shit because with proper cooling these leds should be going solid for at least twice that.

as a customer i want to help push the companies to put proper cooling systems to their fixtures. overbuild this shit so it stays barely a couple of degrees warmer than the ambient temps. the cheapest part of these fixtures is the aluminium so why not build it better with bigger heatsinks.

i’m not even gonna get into the active cooling because it works so so well but less moving parts is somehow a selling point for people. i had the cheapest shittiest 12v pc fans on my cob diy fixture and not a single one failed in 4 years. these can be built to enable easy repairs to change out the fans with new ones periodically even if they havent failed yet but whatever.

if you’re gonna build a light with no moving parts at least do it correctly with serious bulk to dissipate the heat properly @MarsHydrofactory @MedicGrow @Stephenj37826

fell free to tag any other company please these are the only ones i know which advertise on riu
 
Last edited:

Rocket Soul

Well-Known Member
..they make these bar type lights or whatever with properly overbuilt heatsinks. i recently watched a migro video where he evaluated different lights based on their par loss including his own and concluded that in 4 years they will be at 80% or something.

so you gotta change out your fixtures every 4 years if driving at 100% and heatsinks are getting above 40-45C. thats just shit because with proper cooling these leds should be going solid for at least twice that.

as a customer i want to help push the companies to put proper cooling systems to their fixtures. overbuild this shit so it stays barely a couple of degrees warmer than the ambient temps. the cheapest part of these fixtures is the aluminium so why not build it better with bigger heatsinks.

i’m not even gonna get into the active cooling because it works so so well but less moving parts is somehow a selling point for people. i had the cheapest shittiest 12v pc fans on my cob diy fixture and not a single one failed in 4 years. these can be built to enable easy repairs to change out the fans with new ones periodically even if they havent failed yet but whatever.

if you’re gonna build a light with no moving parts at least do it correctly with serious bulk to dissipate the heat properly @MarsHydrofactory @MedicGrow @Stephenj37826

fell free to tag any other company please these are the only ones i know which advertise on riu
Youre quite right that there is a discrepancy between datasheet stated performance over time and what migro found in his tests. I can only see one difference between datasheet and migro test conditions and its power per diode: the tests are running the diodes harder, at about .4w per diode where datasheet seems to be nominal power; .2w.
My take is to use more diodes and leverage diode count, rather than running diodes harder.
Another idea for anyone evaluating which diode to use: dont check only for efficiency also factor in thermal resistance of the diode, it varies quite a lot between diodes and its surprising but some older diodes, f ex lm561c/h, have better thermal resistance than newer lm301b. Thermal resistance is relevant in that it determines how much hotter the diode gets with regards to its heatsink.
 

crimsonecho

Well-Known Member
Youre quite right that there is a discrepancy between datasheet stated performance over time and what migro found in his tests. I can only see one difference between datasheet and migro test conditions and its power per diode: the tests are running the diodes harder, at about .4w per diode where datasheet seems to be nominal power; .2w.
My take is to use more diodes and leverage diode count, rather than running diodes harder.
Another idea for anyone evaluating which diode to use: dont check only for efficiency also factor in thermal resistance of the diode, it varies quite a lot between diodes and its surprising but some older diodes, f ex lm561c/h, have better thermal resistance than newer lm301b. Thermal resistance is relevant in that it determines how much hotter the diode gets with regards to its heatsink.
all very valid inputs however as i said the cheapest part of a fixture is the freaking aluminium isnt it so add more of it in either case. increasing diode count could possibly influence the price even more than the cost of aluminium. and if using diodes with worse thermal resistance than account for that in the fixtures. either case we need way better thermal management on these units to get the best out of them. i think consumers should demand better and the companies should deliver. i dont want to buy 450w fixtures and drive it at 50% to keep it running cool.
 

cobshopgrow

Well-Known Member
the cost of the extruded parts is probably higher then the cost for the diodes on a PCB.
what rocket said, makes absolute sense, to increase the diode count then to spend the money in the heatsinks.
heatsinks increase the shipping price also and theire really not even needed if you drive your 3cent a pc mid power led low enough.
you can easilly reach "just a few degree above ambient" this way.
 

crimsonecho

Well-Known Member
the cost of the extruded parts is probably higher then the cost for the diodes on a PCB.
what rocket said, makes absolute sense, to increase the diode count then to spend the money in the heatsinks.
heatsinks increase the shipping price also and theire really not even needed if you drive your 3cent a pc mid power led low enough.
you can easilly reach "just a few degree above ambient" this way.
i’m not saying what rocket said doesnt makes sense but more diodes means a tighter fit over the whole panel if the pcb dimensions stay the same so a higher density of diodes will still put out considerable heat. aluminium is not very pricey either if you add 100 diodes you add what 3 buck but i’m guessing for this to be effective you should double the diode count or something on most fixtures and 1500-2000 of new diodes can quickly add up too. plus with a density like that you gotta go with bigger heatsinks because the diodes on most fixtures are already tightly packed. so i think both of these methods should be applied simultaneously.
 

harrychilds

Well-Known Member
Do you know what annoys me? Lumatek made a LED called the Zeus PRO and it has magnets that connect the led bars to the fixture and every time I bump my head on a LED strip it falls down onto my plants and stresses them. I mean all they had to do was add a screw fitting so I could screw them directly into the fixture.
 

crimsonecho

Well-Known Member
Do you know what annoys me? Lumatek made a LED called the Zeus PRO and it has magnets that connect the led bars to the fixture and every time I bump my head on a LED strip it falls down onto my plants and stresses them. I mean all they had to do was add a screw fitting so I could screw them directly into the fixture.
is it running cool :)
 

crimsonecho

Well-Known Member
It runs cool at 25% and 50%, but at 100% it runs hot like a 600 watt HPS bulb. I was always told they were supposed to run cool, but clearly not! lol bongsmilie
yeah my lumatek attis is the same way at 20 you cant feel it, at 40 its warm, at 60 the heat is there definitely i havent upped the wattage more than that because i want to keep them cool. and i believe these lumatek fixture are some of the cooler ones in the market. only opticled peaked my interest with their thermal management but its a hassle to ship internationally etc..
 

crimsonecho

Well-Known Member
What temp are you looking for? Non of them are going to be cooler than the temperature of your room.
not talking about cooler than my room :)
how would that even work i guess maybe with a peltier module or something lol
i’m talking like under 30C maybe in a 26-27C room with air con to keep the room steady at that temp.
 

NanoGadget

Well-Known Member
I have the luxury of being able to run more boards at lower power for super even coverage and cooler temps (hopefully resulting in longer diode life), but not everybody has the money to do so. i do think the cooling solutions from manufacturers of plug and play fixtures should be improved if they are going to allow the diodes to be run as hard as they are in most fixtures at %100 power.
 

harrychilds

Well-Known Member
I have the luxury of being able to run more boards at lower power for super even coverage and cooler temps (hopefully resulting in longer diode life), but not everybody has the money to do so. i do think the cooling solutions from manufacturers of plug and play fixtures should be improved if they are going to allow the diodes to be run as hard as they are in most fixtures at %100 power.
I have thought about this and even if you had more boards at a lower power surely you wouldn't get the same results as the light if it was on 100%. I hope that makes sense I am high lol :bigjoint:
 
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