DIY Passive cooling with PIN Heatsinks SST120 and SST140

captainmorgan

Well-Known Member

Lopez7808

Active Member
Hey dropping some information on a Portland guy who is getting ready to manufacture cxb casing for the DIY crowd. They will be 28" x 28" x 2 1/2" or 3" he said they will be blanks meaning no holes and unpainted. Drop the guy a email if interested [email protected].
 

robincnn

Well-Known Member
@captainmorgan
Currently I have them for $24.75 each. Will be down to $24 in 10 days.

For 18pcs box. It will be around $22 each.
Another price break for 50+ pcs

They are more expensive than the $19 SST140. This is due to new mold cost for splay process, cost for plastic packaging and bigger boxes.
140mm were wrapped in bubble bag and the pins bent as they hit each other in shipping.

SST X runs about 7C-8C cooler than SST140 at around 100 watts.
SST X runs about 5C-6C cooler than SST140 at around 75 watts.

I made this one with 100 COB watts per heatsink
upload_2016-11-8_19-42-33.png
 

captainmorgan

Well-Known Member
@captainmorgan
Currently I have them for $24.75 each. Will be down to $24 in 10 days.

For 18pcs box. It will be around $22 each.
Another price break for 50+ pcs

They are more expensive than the $19 SST140. This is due to new mold cost for splay process, cost for plastic packaging and bigger boxes.
140mm were wrapped in bubble bag and the pins bent as they hit each other in shipping.

SST X runs about 7C-8C cooler than SST140 at around 100 watts.
SST X runs about 5C-6C cooler than SST140 at around 75 watts.

I made this one with 100 COB watts per heatsink
View attachment 3826275
Thanks robinccn, have you done any comparisons with lower drive currents, like 1400ma and 1050 ma?
 

robincnn

Well-Known Member
@captainmorgan
No i did not test 140 vs splay at lower current. 75 was min.
Let me know if you have any recommendation for a test and I will try to get it done this weekend.

At 1400ma i recommend 120mm. 1050ma with 105mm
at 50 watts the difference between the 120mm and 140mm is very small. 2C-4C i think. 140 has thicker pins. 120 has thinner and a lot more pins.
Going overkill on passive does not help much. Only adds cost and weight.
Assuming airflow in grow space the 120 and 140 may perform within 1C.
 

Lopez7808

Active Member
Question. If I push my cxb3590 CD bin 36v lights to 100 watts can the commonly available black anodized aluminum heads 140mm x 70mm can I expect thermal breakdown of the chip???
 

captainmorgan

Well-Known Member
@captainmorgan
No i did not test 140 vs splay at lower current. 75 was min.
Let me know if you have any recommendation for a test and I will try to get it done this weekend.

At 1400ma i recommend 120mm. 1050ma with 105mm
at 50 watts the difference between the 120mm and 140mm is very small. 2C-4C i think. 140 has thicker pins. 120 has thinner and a lot more pins.
Going overkill on passive does not help much. Only adds cost and weight.
Assuming airflow in grow space the 120 and 140 may perform within 1C.
It would be easy for people to make a decision on heatsinks if you could make up a chart with the different sizes and currents with their junction temps,even with lower currents.
 

BuddyColas

Well-Known Member
@captainmorgan , I will have to agree with you on that Sir
Now I'm not pissing in your Cheerios mate, but the NGL site has all the numbers you need...in my opinion.


SST105
Recommended Watts** 25W to 35W Led or 20W Heat
Thermal Resistance** 1.2 C/W

SST120
Recommended Watts** 35W to 60W Led or 35W Heat
Thermal Resistance** 1.00 C/W

SST140
Recommended Watts** 50W to 80W Led or 25W to 50W Heat
Thermal Resistance** 0.75 C/W

SST X-rated!
Recommended Watts** 80W to 100W Led or 60W Heat
Thermal Resistance** 0.60 C/W
 

captainmorgan

Well-Known Member
Now I'm not pissing in your Cheerios mate, but the NGL site has all the numbers you need...in my opinion.


SST105
Recommended Watts** 25W to 35W Led or 20W Heat
Thermal Resistance** 1.2 C/W

SST120
Recommended Watts** 35W to 60W Led or 35W Heat
Thermal Resistance** 1.00 C/W

SST140
Recommended Watts** 50W to 80W Led or 25W to 50W Heat
Thermal Resistance** 0.75 C/W

SST X-rated!
Recommended Watts** 80W to 100W Led or 60W Heat
Thermal Resistance** 0.60 C/W
I know the recommendations but it would be nice to see the real junction temps at the different currents.
 

robincnn

Well-Known Member
@BuddyColas those are estimates online. The thermal resistance changes non linearly with wattage.

I know the recommendations but it would be nice to see the real junction temps at the different currents.
Hard to test check case temps with Vero 29 as Tsp is not easily accessible. No Tsp with Citizen.
Will test case temps some with Cree 3590 next week at different current and report back.
The test data is under no air movement and things change a lot in tent with air movement
 

Lopez7808

Active Member
Running the test with no air movement is probably the best way to go. It would be a platform to base it on inline fan failure.
Testing with air movement has to many variables when it come to a variety cfm.
 

robincnn

Well-Known Member
@The Dawg Please share Tea recipe for my tomato plant when you get time.


Moved my tomato plant from a 3 gallon to a 5 gallon pot.
2x2.5 tent. Photon 180 lamp 190 watts
Canopy is thick and leaves on top feel a little moist... should i do some trimming to improve light penetration and avoid mold?


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