Any alternatives to oscillating fans to cool led qb ?

Smokeytit90

Active Member
Some sort of cool tube that an take the heat .

My temps aren't overly high but they have the potential.

Highest right now is 31°c

Want to get down to 26°c

Airflow I think is fine as is . Maybe add an oscillating fan

Wondering if I can cool the light directly in a more efficient way
 

Smokeytit90

Active Member
Directing a fan at the light will not reduce the temps inside your tent/room. The heat is not eliminated, simply dispersed.
What if it's a cooling fan ?

I'll need some better extraction an inline fan but atm need an very quiet one affinity looks like the most quiet but still probably fairly loud
 

lusidghost

Well-Known Member
What if it's a cooling fan ?

I'll need some better extraction an inline fan but atm need an very quiet one affinity looks like the most quiet but still probably fairly loud
Aren't all fans cooling fans? It's good to have a fan on the light to keep it cool for longevity purposes, but you're either going to need an AC or exhaust fans sucking out the hot air.
 

ilovereggae

Well-Known Member
Directing a fan at the light will not reduce the temps inside your tent/room. The heat is not eliminated, simply dispersed.
this is not 100% accurate. as I understand, using active cooling keeps the heat from building up, which keeps the overall heatsink cooler. otherwise the buildup of heat can cause the led to draw more current resulting in even more heat. I'm not sure that's 100% accurate either, but I know from experience if I blow a fan on my sinks and externally mounted drivers, they stay cool to the touch, and my temps in my tent and driver closet barely move. if I don't use active cooling in the tent, I can expect about a 3-5F degree temp increase per 250W of lights.

Some sort of cool tube that an take the heat .

My temps aren't overly high but they have the potential.

Highest right now is 31°c

Want to get down to 26°c

Airflow I think is fine as is . Maybe add an oscillating fan

Wondering if I can cool the light directly in a more efficient way
I would suggest looking at PC fans. some ppl have made 3D printed housings to attach them. depending on your driver you might even be able to run them off that circuit so u don't need another power cord. or the quick fix I've done in the past is to zip tie a hurricane fan to the ceiling of the tent above the QB.
 

Smokeytit90

Active Member
this is not 100% accurate. as I understand, using active cooling keeps the heat from building up, which keeps the overall heatsink cooler. otherwise the buildup of heat can cause the led to draw more current resulting in even more heat. I'm not sure that's 100% accurate either, but I know from experience if I blow a fan on my sinks and externally mounted drivers, they stay cool to the touch, and my temps in my tent and driver closet barely move. if I don't use active cooling in the tent, I can expect about a 3-5F degree temp increase per 250W of lights.



I would suggest looking at PC fans. some ppl have made 3D printed housings to attach them. depending on your driver you might even be able to run them off that circuit so u don't need another power cord. or the quick fix I've done in the past is to zip tie a hurricane fan to the ceiling of the tent above the QB.
this is not 100% accurate. as I understand, using active cooling keeps the heat from building up, which keeps the overall heatsink cooler. otherwise the buildup of heat can cause the led to draw more current resulting in even more heat. I'm not sure that's 100% accurate either, but I know from experience if I blow a fan on my sinks and externally mounted drivers, they stay cool to the touch, and my temps in my tent and driver closet barely move. if I don't use active cooling in the tent, I can expect about a 3-5F degree temp increase per 250W of lights.



I would suggest looking at PC fans. some ppl have made 3D printed housings to attach them. depending on your driver you might even be able to run them off that circuit so u don't need another power cord. or the quick fix I've done in the past is to zip tie a hurricane fan to the ceiling of the tent above the QB.
Nice . The PC fans did the trick I have 4 fans on rubber stands which just catch enough grip . Total cfm 220 . Just sitting on each corner of the quantum board . Qb is now completely cool and tent gas dropped about 5°c
 
Last edited:

Billy the Mountain

Well-Known Member
this is not 100% accurate. as I understand, using active cooling keeps the heat from building up, which keeps the overall heatsink cooler. otherwise the buildup of heat can cause the led to draw more current resulting in even more heat. I'm not sure that's 100% accurate either, but I know from experience if I blow a fan on my sinks and externally mounted drivers, they stay cool to the touch, and my temps in my tent and driver closet barely move. if I don't use active cooling in the tent, I can expect about a 3-5F degree temp increase per 250W of lights.



I would suggest looking at PC fans. some ppl have made 3D printed housings to attach them. depending on your driver you might even be able to run them off that circuit so u don't need another power cord. or the quick fix I've done in the past is to zip tie a hurricane fan to the ceiling of the tent above the QB.
Unless the laws of thermodynamics have changed, it is indeed accurate.

A watt is a watt is a watt = 3.41 BTU
 

ilovereggae

Well-Known Member
It's hanging at the top of the tent .. need to get more 18g wire and some wago connectors and I'll move it to outside
that will help too and should shave a few more degrees off tent temps.

Unless the laws of thermodynamics have changed, it is indeed accurate.

A watt is a watt is a watt = 3.41 BTU
have you tested what I am suggesting? I understand what you are saying on paper. in practice, aiming a fan at top of my QBs or drivers and dissipating the heat before it builds up results in significantly cooler environment. less build up means less extracting. I understand thermodynamics, do you understand what I'm saying that if the module runs warmer it will draw more current resulting in higher wattage and therefor temps? I'm not sure of the exact terminology but same priinciple that can lead to thermal runaway. but besides that, actively cooling a module and not allowing it to build up heat must have another term for it. I know for a fact I can measure the difference between using active cooling and not. and @Smokeytit90 just confirmed it. sorry I am not book smart enough to tell your the math formulas at work. but I know from having tried it since I started using LEDs.
 

Hiddengems

Well-Known Member
Unless the laws of thermodynamics have changed, it is indeed accurate.

A watt is a watt is a watt = 3.41 BTU
1 watt of electricity has the same total output for led and hid, but they differ in the percentage of what gets turned into light and heat.

He's also somewhat right about cooling the sink. Electronics are less efficient as temps rise, this leads to drawing more current to do the same work with the inefficiencies stacking to add even more heat.
 

Billy the Mountain

Well-Known Member
1 watt of electricity has the same total output for led and hid, but they differ in the percentage of what gets turned into light and heat.

He's also somewhat right about cooling the sink. Electronics are less efficient as temps rise, this leads to drawing more current to do the same work with the inefficiencies stacking to add even more heat.
HID's are much less efficient and output a lot of IR

A 300W HID fixture and a 300W LED fixture will produce the exact same amount of heat. Main difference is that the 300W LED produces roughly twice the light for the same watts (heat).

I realize that resistance rises with temperature but the temp difference does not effect output with the few Meanwell drivers I own. Even in the tent, the driver was well within its Tcase rating. Same wattage displayed on kill-a-watt whether inside or outside tent. Any decent driver should behave the same.
 
Last edited:

madvillian420

Well-Known Member
this is not 100% accurate. as I understand, using active cooling keeps the heat from building up, which keeps the overall heatsink cooler. otherwise the buildup of heat can cause the led to draw more current resulting in even more heat. I'm not sure that's 100% accurate either, but I know from experience if I blow a fan on my sinks and externally mounted drivers, they stay cool to the touch, and my temps in my tent and driver closet barely move. if I don't use active cooling in the tent, I can expect about a 3-5F degree temp increase per 250W of lights.
Same. I keep a mini fan blowing on my heatsink mounted drivers at all times now. Absolutely helps.
 

Hiddengems

Well-Known Member
HID's are much less efficient and output a lot of IR

A 300W HID fixture and a 300W LED fixture will produce the exact same amount of heat. Main difference is that the 300W LED produces roughly twice the light for the same watts (heat).

I realize that resistance rises with temperature but the temp difference does not effect output with the few Meanwell drivers I own. Even in the tent, the driver was well within its Tcase rating. Same wattage displayed on kill-a-watt whether inside or outside tent. Any decent driver should behave the same.
If you add up the total photon output per watt the led is more efficient. It adds less heat to its environment per watt of electricity.

If you add up total energy output, photon energies and heat, both fixtures put out the same energy. But for the same input energy the led puts out less btu's.

It basically works like this. With 100% efficiency a light puts out 100w worth of photon energy for every 100w of input, and zero heat not from reabsorbtion of photon energy from the surroundings. 50% efficiency turns half the energy into photons and about 1.7 btu's of heat.
 

Billy the Mountain

Well-Known Member
If you add up the total photon output per watt the led is more efficient. It adds less heat to its environment per watt of electricity.

If you add up total energy output, photon energies and heat, both fixtures put out the same energy. But for the same input energy the led puts out less btu's.

It basically works like this. With 100% efficiency a light puts out 100w worth of photon energy for every 100w of input, and zero heat not from reabsorbtion of photon energy from the surroundings. 50% efficiency turns half the energy into photons and about 1.7 btu's of heat.
No, thats not how it works. A watt is a watt is a watt = 3.41 BTU
 
Top