I have noticed quite a few questions about the suitability of the store's
heat sinks for various projects, and since I have tested and documented
most of them here, I am happy to present my list of the sinks and their
respective thermal resistance numbers. Toward the bottom it lists the
wattage for a 30 deg C rise on a single side and the number of TO3-P
type packages it is drilled for.
heat sinks for various projects, and since I have tested and documented
most of them here, I am happy to present my list of the sinks and their
respective thermal resistance numbers. Toward the bottom it lists the
wattage for a 30 deg C rise on a single side and the number of TO3-P
type packages it is drilled for.
30 above make them dangerous in Summer
OK, everyone would say - AC in Summer
I don't have and I don't need AC in house, in fact avoiding it as long I can ( until Ozone and age prevail)
in workshop I must use AC but even there no more than few degs down from outer temp, that and decreased humidity enough to keep my forehead ( thus spectacles) free of sweat
more than few degs means more care while mingling in-out-in-out, no good
that combined with my cap OCD, means +25 and Babysitter(s) active in Summer
heck, I'm not in Ca, my Whales are more up in Clouds ...... which means they're even more visible than ones moving through SR shores
You mean CDO?.... Letters MUST be in order alphabeticallythat combined with my cap OCD
Well, the listed 5U is the 400mm deep version. Still , it does seem a bit high compare with the others.
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What can I say? I mounted some power resistors on the sinks just sitting there vertically on the bench.
Even if the figures are approximate, it gives a feel for what they can do, and YMMV.
Same, here in USA, NY. But then, we don't get >30C as often here.
But really? This is DIY.
- Change to a bigger heatsink.
- Or piggyback another heatsink.
- Or dive into making a quieter fan.
- Or figure out how to live with lower power. "The first watt is the most important watt."
Kind regards,
Drew
Not necessarily. A Class AB amp wouldn't dissipate the full power except when you really crank it. Planning for 30 ºC rise is perfectly reasonable.
Now Class A amps on the other hand would get quite hot if the room is hot. Perhaps dial down the bias during the summer.
Thanks to Nelson for taking and making these data available. It's good with some real-world data.
Tom
I have tested the 5U400 with my BA-3 3 deep biased pretty high. @ 130-ish watts the sinks were approximately 65 degrees measured close to the output devices. That meant approximately 60-62 degrees celsius at the top of the sinks, 35-ish above ambient. I used Kheraterm, that might have had something to do with it. But most importantly the amp was positioned in a non optimally ventilated location, OK but not optimal.What can I say? I mounted some power resistors on the sinks just sitting there on the bench.
Even if the figures are approximate, it gives a feel for what they can do, and YMMV.
I did use it like that for quite a while, and loved every milliamp of extra Iq on my Fynes. But Mighty did give me fair warning, and so I biased it lower during the summer months. I am both fearless greedy boy and a sissy at the same time, FSGB for short
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I have tested the 5U400 with my BA-3 3 deep biased pretty high. @ 130-ish watts the sinks were approximately 65 degrees measured close to the output devices....
.... and so I biased it lower during the summer months. I am both fearless greedy boy and a sissy at the same time, FSGB for short
Interesting idea... either add a knob to dial the bias or put in a switch circuit marked Summer / Winter with a red switch (and RED LED) on the front panel.
My living room gets hot in the summer, around 84F without running the AC. And the A2s (5U400s) run hot all the time, pretty much out on the open. so it becomes a feedback circuit with the amps acting as heaters in a hot room. The AC here in Coastal SoCal is affordable only by politicians and Hollywood Royalty. So, when it gets pretty hot, I switch to a tube amp.... or just don't listen.
Running the AC is not only expensive, but the flow of air does make some noise.
We have two units, four zones already. The units are 20 years old and work fine but are no longer maintainable because in Calimexistan they changed the rules. And for 1KwH of monthly power our bill is $380 per month -winter. When we ran the AC in August and September, we ran 1500 KwH and our bill was almost 600 bucks ( this is near the coast, just keeping the house at 78F! ).
We looked at solar.... got into a contract, around $55K for 12 Kw latest design solar cells and solar battery. Pulled out because their design won't do what we want (off grid in suburbia).
We've looked at ductless splits... will require some work since the house is spread out... giving us likely 10 zones, nice, but about $50K with three locations for the outside compressors.
We've looked at updating our current systems, up to five zones... have had a contract signed to update, plus do some more work to the roof, eaves, some additional electrical, but the contractor -I guy who did our house- is having issues getting his subs. The HVAC will run about $40K.
In the meantime, we got class D Nuforce DDA100/120 amps in our offices, so we run the AC in those rooms during the day time in the heat of the summer on only kick in the main house and upstairs at around 3PM to "chill" that down to 78F.
Maybe, I ought to put some 100U, 1000mm heat sinks on the North Wall of the house?
Good grief. I thought my area was bad. 1KwH here in central VT is around $230 which I thought was bad since my parents in Austin TX pay around $100-$120 for 1.6KwH.
I didn't realize the solar panel pricing was so high. That option makes some sense as I don't expect the situation to get much better any time soon. Resources in CA seem to be depleting which means more demand. It sounds like you have done your diligence, but if you look up Matt Risinger with the build show, he builds houses that are fairly efficient and provides a lot of insight on air sealing, insulation etc. He is also in a mainly dry mainly cooling climate so a lot of the info should apply to you.
I invested in a cheapish thermal camera and it was pretty eye-opening. Here in VT, the key is to trap the heat in. I heat with a wood stove and have noticed the wood usage go down every time I do a few things here and there. If you can get your house to use less electricity, then you won't need as large of a solar panel setup. Maybe 9Kw instead of 12 for instance.
Mini splits are used in studios due to their lack of noise. Having spent time with them, I can confirm that. Also, they are more efficient. A lot of the air going through your ducts in an unconditioned attic space leaks out into that space. I believe the thought is around 20% of your cooling. Not to mention the low seer ratings etc. I used to live in FL and a couple had a mini split that was rigged so that they could plug their briefcase (honda) generator into directly during a power outage, hurricane etc.
Sorry for derailing the topic.
I didn't realize the solar panel pricing was so high. That option makes some sense as I don't expect the situation to get much better any time soon. Resources in CA seem to be depleting which means more demand. It sounds like you have done your diligence, but if you look up Matt Risinger with the build show, he builds houses that are fairly efficient and provides a lot of insight on air sealing, insulation etc. He is also in a mainly dry mainly cooling climate so a lot of the info should apply to you.
I invested in a cheapish thermal camera and it was pretty eye-opening. Here in VT, the key is to trap the heat in. I heat with a wood stove and have noticed the wood usage go down every time I do a few things here and there. If you can get your house to use less electricity, then you won't need as large of a solar panel setup. Maybe 9Kw instead of 12 for instance.
Mini splits are used in studios due to their lack of noise. Having spent time with them, I can confirm that. Also, they are more efficient. A lot of the air going through your ducts in an unconditioned attic space leaks out into that space. I believe the thought is around 20% of your cooling. Not to mention the low seer ratings etc. I used to live in FL and a couple had a mini split that was rigged so that they could plug their briefcase (honda) generator into directly during a power outage, hurricane etc.
Sorry for derailing the topic.
We rebuilt the house in 2000. It is insulated quite well. Our building codes are strict. I'm pretty sure the amps in the 5U chassis will surpass all our codes for sure, they look heavily braced to withstand the Big One.
Here in Calimexistan we are NOT running out of resources, we are floating on seas of oil and natural gas. We have an artificial shortage, you see.
Our rates are based on tiers... in winter, I have a 3rd baseline above 1500 KwH where our KwH are charged at ~45 cents.... figure that out. I think there's another tier above it... there they come to your door at 3AM and take you away for reeducation...
The HVAC we've contracted to install is a dual variable air flow systems, also we are putting in a "cool" roof which reflects 20% of the solar energy, that should also cool down the house.
Maybe we could build our house into an "Aleph House" with heatsinks on the East, North and West walls!