Best pelt to simulate ~200watt heat load

[stockhatch]

Im wondering what pelt would be good for testing/tuning for a ~200 watt heat load? I dont understand the whole listed rating + some other number thing? Can somebody explain this to me? IOW, I hear a 75watt pelt doesnt simulate a 75watt load, but some other load based on a formula. Help!

[gkiing]

I think a 150W would be about there.. from what I've experienced a pelteir puts out more heat than it's rating (80w is around 130w etc).

[stockhatch]

Hmmmm okie doke, thanks. Ill keep that number in mind. Anyone else? Maybe somebody can supply the magic formula?

Thanks :)

[wdrzal]

there is a company in new jersey that makes these, the owner emailed great information packet,now here's the "BuT" :( my controler failed on my hard drive and I can't retreive that info,If I think of company name I will get them to resend it.anybody have a 60 gig ibm hard drive,I'm pretty sure the data is all their if a can find a controler and swap it. walt

[stockhatch]

So how would I go about hooking something like this up? I read of others using a water block on the cold side of the pelt, is this necessary? I couldn't just take a pelt, bolt it to the evap and crank it up?

[wdrzal]

So how would I go about hooking something like this up? I read of others using a water block on the cold side of the pelt, is this necessary? I couldn't just take a pelt, bolt it to the evap and crank it up?
edit. gave wrong answer fingers were in motion before brain was engaged.

you must never operate a tec without a heatsink on the hot side,a cold evaporator is a heat sink,just be sure evap is cold before applying power to tec.

[crotale]

Measure the amps through it and you'll know how much heat it generates.
It's quite impossible to get 130W of heat from it if you only give it 80W of electric power.
You might reach 130W if you add a GPU of 50W on the cold side, but that's an other story.

[wdrzal]

Note: It is important when purchasing a tec that you buy one the is "edge sealed" not all tec are. moisture (frost) will ruin it.

[stockhatch]

Ok, so if I buy a 170watt pelt, and bolt it directly to the evap thats fine? As long as the evap is cold before I power it up? How much heat would this put through the evap?(assuming max voltage in on a 170watt pelt) And I wouldnt have to put anything on the other side?

[saratoga]

Measure the amps through it and you'll know how much heat it generates.
It's quite impossible to get 130W of heat from it if you only give it 80W of electric power.



:rolleyes: Its a heatpump; it pumps heat. That heat shows up on the hotside after being removed from the cold side. A TEC that only output as much heat as W = V*I calculated would be a resistor.


You might reach 130W if you add a GPU of 50W on the cold side, but that's an other story.

Doesn't have to be a GPU. Any source of potiential energy will work. Including air at room temp. However changing the cold side temp will change the COP, so your load will vary somewhat. However if you're using a TEC, you're probably not too worried about exact dissipation.

[wdrzal]

stockhatch;I can't remember the formula to calculate load,just go to the tec heading I'm sure the calculations are in the stickys,if you are unsure just ask the guys there that use them all the time. walt

[stockhatch]

stockhatch;I can't remember the formula to calculate load,just go to the tec heading I'm sure the calculations are in the stickys,if you are unsure just ask the guys there that use them all the time. walt

LOL! There is a TEC section!!! I had no idea :D The phase change forum is where I have been living for the most part, so I have been ignoring the other parts of XS :D Ill go check that out.

[stockhatch]

Ok, I have found a calculator that spits out an overclocked wattage of ~150 for my prescott. Why everyone suggests 180-200watts I have no idea. Maybe they are correct, I dont know. My question is, should I go through the hassle of setting up my DD, or will it fail to keep up at all? I am using a 600btu Embraco. If it will definitely work I can avoid this whole load testing hassle :D

[wdrzal]

Ok, I have found a calculator that spits out an overclocked wattage of ~150 for my prescott. Why everyone suggests 180-200watts I have no idea. Maybe they are correct, I dont know. My question is, should I go through the hassle of setting up my DD, or will it fail to keep up at all? I am using a 600btu Embraco. If it will definitely work I can avoid this whole load testing hassle :D

Always ask Why,why,why if some gives you a answer to a
question,get a explanation of how they got that answer.Remember how the "engineers" do it,if dosn't work on paper it won't work in real life!!!
Besides, paper is cheap :) parts are not :( walt

[saratoga]

CPU wattage calculators are extremely rough estimates. They're just scaling for the voltage and CPU speed according to EE rules of thumb. For this reason, its a good idea to error on the side of caution.

[wdrzal]

CPU wattage calculators are extremely rough estimates. They're just scaling for the voltage and CPU speed according to EE rules of thumb. For this reason, its a good idea to error on the side of caution.

I thought we were talking about tec's wattage walt

[saratoga]

^^ I read it as him asking how to simulate a 200w heatload with a TEC, which is the estimated load of the prescott he wants to cool. If he meant the TEC, then just ignore me.

[wdrzal]

^^ I read it as him asking how to simulate a 200w heatload with a TEC, which is the estimated load of the prescott he wants to cool. If he meant the TEC, then just ignore me.

you got it right,but "simulating" the load of the presott means having a "tec " put out the same load as the chip would,200 watts

[WindStorm]

Don’t you have to reach 18 volt to get full penitential of a pelt. If your running it off of a 12 volts power supply it should be around 80 percent. So if I am running 80-wattage pelt at 12v it put out 64 wattage and 200-wattage pelt at 12 volts it would be 160 wattage of power correct me if this is incorrect

[kayl]

Measure the amps through it and you'll know how much heat it generates.
It's quite impossible to get 130W of heat from it if you only give it 80W of electric power.
You might reach 130W if you add a GPU of 50W on the cold side, but that's an other story.


a tec is a heat pump, so its got electrical heat then heat added pumped through the tec.
ya need to insulate it or its a larger load.
either way its gonna be more heat than rated as its drawing heat from the copper plate on the hot side so can get a good contact to ensure its got load, and use heatcompound.
i have used a 130w tec before, 80w as well. 226 would be over kill.
ya cant beat a real load though, when better to tune than when surfing xs :pimp:

[crotale]

:rolleyes: Its a heatpump; it pumps heat. That heat shows up on the hotside after being removed from the cold side. A TEC that only output as much heat as W = V*I calculated would be a resistor.

Doesn't have to be a GPU. Any source of potiential energy will work. Including air at room temp. However changing the cold side temp will change the COP, so your load will vary somewhat. However if you're using a TEC, you're probably not too worried about exact dissipation.


Yes, right, but what I meant was that you can't say a 80W TEC automaticly put out 130W, continuously, on the hot side. If you isolate the TEC's cold side (ideally), it would only put out as many W as you put into it.

I would recommend anyone serious in building a power load to go with power resistors. Just bolt them to a copper plate and isolate it as good as possible from ambient air. Just meassure the amps you send through it and what voltage you have over it and you'll have pretty much the exact heat output from it.

[wdrzal]

Yes, right, but what I meant was that you can't say a 80W TEC automaticly put out 130W, continuously, on the hot side. If you isolate the TEC's cold side (ideally), it would only put out as many W as you put into it.

I would recommend anyone serious in building a power load to go with power resistors. Just bolt them to a copper plate and isolate it as good as possible from ambient air. Just meassure the amps you send through it and what voltage you have over it and you'll have pretty much the exact heat output from it.

I agree, resistors are infinatly variable up to their rated capicity.cheap to buy and can be regulated easily. this way one set up should be all that is needed to do all your testing. walt

[stockhatch]

Ok so back to my other question, do you think I should even bother hooking this thing up to my prescott@4Ghz? Or would it not handle the load at all?

[kayl]

yeah hook it and charge according.
it should hold at least -20c.
i got -30c load at 130w cpu.
but the 180w and newer cpus take more heat.
if you run about say 8psig it should hold load well.
just shorten the capillary line also for more capacity.
it can be done.
put probe on evap and on suction line and tune it.

[stockhatch]

Great. Thanks. I also just got word back from Americold on my mystery compressor and it is a 700 BTU unit. Looks like I have the makings of another setup :)

[DGeNeRaT3]

I got an unrelated question to the topic. I have 2 rather large compressors but i can't find the horsepower rateing on them all the other information is listed but the horsepower rating is missing. The only thing i can find listed on it is "1 PH" does this mean "one power horse?" if anyone can enlighten me please let me know.

Thanks

[kayl]

nar ph1 just means normal voltage.
ie ph3 if its 3 phase. that gets everyone.

[stockhatch]

I got an unrelated question to the topic. I have 2 rather large compressors but i can't find the horsepower rateing on them all the other information is listed but the horsepower rating is missing. The only thing i can find listed on it is "1 PH" does this mean "one power horse?" if anyone can enlighten me please let me know.

Thanks

Do what I did and contact the manufacturer directly. I got an email back within an hour.

[DGeNeRaT3]

These came in SEARS air conditioners and they were very unspecific in the description of the compressors used. The information provided are things like hz and BTU's and stuff like that i can't even find a name on them. No big deal i'll make a thread later on and maybe post pics of the name plates and stuff.

[stockhatch]

Ah I see. Well good luck with that.

[reject]

yeh man, hook it onto your presscot. if it doesnt handle the laod, your doing somthing wrong :)

[stockhatch]

Alot of people have used compressors that were too small with negative results...That was my main concern, not my ability to put a system together(though that may turn out to be an issue too :D )