Where you buy yer pelts from?

[Cablepro]

I'm sorry to keep buggin ya, but I really need the help, and I really appreciate it...

ok...i'm thinking of selling this 172W 24V peltier, because I just can't afford the power supply necessary...

however, i think i'll get a peltier that is rated at 16V... a 156W 16V 16A peltier...the manufacturer says I need a 12V 25A power supply for this(does this make sense?)...will this peltier produce the 120-140W i'm looking for with the 12V supply? or is this too strong of a peltier?

thanks

[Rich W]

No prob.. just busy here.... circuits homework again.

When you say this:
"as far as the capacitor is concerned, I don't see any numbers or anything anywhere...it's a big blue thing about the size of a soda can, and connected to the terminals is a little square block that says 5000W(i believe to aid in getting rid of the juice when it's turned off?)..."

That little square black thing... how is it (if it is at all) connected to the transformer? Are there 2 or 4 leads on it?Are there any other things in the power supply? As for the capacitor size, I have caps that are almost the size of a half gallon of milk and are almost 10,000uF and 75 Volt... but I also have some that are the size of a chap stick holder that are 2,300uF and 50 Volt.. just depends on the technology used and the voltage they are capable of.

As for selling the peltier, don't yet... lemme know what that black thing says. And who is the 'manufacturer' of this other peltier?

[Cablepro]

looks like it says 5W 500 (Ohm sign omega?) then J
it's grey and it's connected with 2 leads...one to each terminal

The manufacturers of both peltiers are Tedist...

I talked to Tedist today, and they told me to power the 172W 24V pelt, I need a 24V power supply that can do minimum 14amps...
and he said that the 156W 15.8V pelt, I would need a 12V power supply that can do 25amps....does any of this make sense?..

heh, i'm getting dizzy

[Rich W]

Hmm.... any new news?

BTW, that little black thing is a resistor, and put there to discharge the capacitor (just like you said...) so that there are no harmful charges anywhere.. otherwise, that could hurt!

I was thinking it might be a halfwave bridge rectifier... if it was, then you could replace it with a full wave for more power, but...

Anyway, lemme know what's up.

[Cablepro]

well, seeing as a 24V power supply good for 12+amps was a bit more than I could afford, I sold the 172W, and bought a 156W 15V peltier...I'm scouring the auctions, but i'm going to buy a 12V 25A power supply...I've got a few ebay auctions I'm watching...but they're going for under $100...

Now I've just about got delivery of all my components, except my waterblock(Swiftech) and my radiators(OCWC)...

But i'm trying to figure out a way to get rid of the heat from the peltier...I was planning to use an aircooled radiator just after the waterblock, and then another radiator submerged in liquid inside a little dorm fridge...I figured the first radiator might pull about 100W of heat away, and then the radiator in the fridge would do the rest...

I thought it would be a good plan, but people are telling me that it will still be too much heat for the dorm fridge(would be about 120W for the peltier, +80W for the cpu, -100W from the first radiator = about 100W of heat)...they say the fridge MIGHT pull the heat off, but it will be running 24/7, and will destroy itself quickly...

so I don't konw what to do now...I"m searching for lab chillers and stuff, but they're really expensive...I probably have MAYBE another $200 I can spend for chilling the water....any suggestions?

[Rich W]

Well, I think they are right about the fridge running all the time + destroying itself (wear out quickly, etc)... but you can cool the water to damn near room temp if the radiator is big enough, that way the heat load for the dorm fridge is about 0 watts, but since the water is being cycled through it it will always be on.. it won't be over powered, but it will harm it from being on so long...

As for the lab chillers, what university do you attend? I'm sure they have surplus auctions.. mine had an auction and I got a helluva lab chiller that chills to like -40 deg C for $9... it was made in 1979, and it draws 15 amps, but it works like a charm... just damned heavy and draws too much.. I keep telling myself I'll hook it up to my current setup (just for a test...) but I haven't yet.

So, the biggest problems you'll face with having a secondary cooler (like a fridge, lab chiller, etc) is that it'll draw a lot of electricity from the wall (a consideration you'll have to deal with), it might detroy it from continuous use (not all equipment is made for continuous duty, etc), and if it is mechanical (ie, a compressor, etc.. I have seen peltier lab chillers.. but that leads to the next problem) it will break eventually. Period. The next problem is how much heat it can handle.... a dorm fridge, as discussed, isn't designed to handle much heat. The same problem arises with other small compressor setups and peltier based lab/medical chillers (although they can control the temperautre much better than compressors...). If they get 'overpowered' by the heat of the load, then they will not work very well and weird things will happen. The last problem is that if you do succeed in cooling down the water/antifreeze mix to below ambient, then you'll need to insulate every part of the hose... unless the output of the waterblock is warmer than ambient... and might as well insulate the rest if for some reason it does go below ambient. If you don't, you'll get condensation.

So, really.... I don't think I'd mess with a second cooler... just more to go wrong, more to haul around, more expense, more noise, more heat generated, more electricity used (and hence more cost).... all for just (in reality) most likely 5 or 10 degrees? I think I'd just keep the money, or spend it on a really good radiator + fan setup (quiet fans).. that'll get you close enough to room temp, and you won't have condenstation issues all over the tubes, excess power draw, excess heat, mechanical failure, etc.

Good luck!
Rich w.

[Cablepro]

thank you so much for your input...that gives me some very good food for thought...so you believe just using those 2 radiators, maybe one before the pump, one after the pump would be good enough? I guess I could always try it, and if they aren't enough, I could add yet another radiator inline...

as long as the water is near ambient, it will keep pumping heat from the peltier, thus chilling the cpu well? Or is the cold side temperature a function of the hotside temp?

[Cablepro]

I'm hyped...Chip at OCWC (the guy who sold me the Big Mamma radiator) told me he's got one on the bench with 400W of heat running through it, and the coolant temp is 4.2C over ambient...but his 120mm fans are running 160cfm at 17V...but perhaps my second radiator will compensate for that...Gabe at Swiftech screwed my order up for my waterblock (lost it), so I cancelled it(2 weeks later), and i'm ordering from Chip...I"ll be sure to let you know how this setup works ...thank you for everything...I appreciate the input bigtime

[Alives]

i decided to use smaller fans and more radiators...less noise