Peltier Chip Damaged????

Hi, you all know me, im the one that had the power supply blow on him. Well after sending it to the manufacturer I recieved the same unit repaired. After powing my pelt for 5 min it blew out AGAIN!!!!! I thought it must be the petlier, but it was functioning normally. . . I took my multmeter to it and it had a reading of 1.0-.9 ohms. Is this normal for a peltier chip? I just want to know if I am *******g at teh manufacturer with good reasons, or if my peltier was a dud all along.

My 120 watter reads 3.4 ohms.
Don't know if that makes much difference, but if it helps, then I'm glad to chip in.

hmm. . . well my chip is 226 watt. . . I'll see if I can come up with a good mathmatical model for it, [edit: found out that Volts/Amps=Ohms]. BTW if you are looking for a good peltier power supply, check this deal out
http://www.buypcdirect.com/product.asp?pf_id=PM400W
25A on the 12v rail. And its only 19.25 w/ shipping
If anyone knows if my resistance is good, plz tell me. thnx

226 Watt TEC right?

A 0.9 to 1 Ohm reading is fairly believable.

As long as the TEC didn't overheat, it is probably fine.

Sounds like the power supply is a POS that is not meeting its specs. (And even if it can't meet its specs it should still have better protection that keeps it from blowing.)

I don't know if I've seen the specs for the supply you are using. Got a link?

I think I'd try to get my money back if the supply is not meeting its specs.

Then buy this supply.

Re: Re: Peltier Chip Damaged????

Since87 said:

Then buy this supply.

Click to expand...

Yeah, that seems to be a nice supply. Nice price, nice size and ok output. The best deal in the states (aside from garagesales/sweet ebay deals)

I'm so sorry for myself, being so stupid to be wanting 2pcs of 0-15 volt/25A supplys... That deal would save me loads of dollars.... or Swedish Kronor where I live..... I... just.. must know.... if.. 3 more volts... will do.. me good.. or bad... Curiosity costs/kills

when it comes to peltiers, 12 is pretty much the limit. Anything above that basically ruins the efficiency of the pelt, and if you don't have an uber cooling system, it will most likely just increase the hot side temp, and the cold side could just stay the same 12 volts should be enough.
P.S. I still need some info about my pelt. Is the 1 ohm correct? Can someone just take a multimeter to their 226 watt pelt and tell me what they get???

edit: hey, I happen to be 25% sweedish

Just taking an ohmmeter to a pelt doesn't work that well. They don't act like pure resistors. See this thread for much more information. (Particularly doc's posts.)

hmm... i don't think the peltier is damaged. Try using another psu on it to test it out.

ookabooka said:

when it comes to peltiers, 12 is pretty much the limit. Anything above that basically ruins the efficiency of the pelt, and if you don't have an uber cooling system, it will most likely just increase the hot side temp, and the cold side could just stay the same 12 volts should be enough.
P.S. I still need some info about my pelt. Is the 1 ohm correct? Can someone just take a multimeter to their 226 watt pelt and tell me what they get???

edit: hey, I happen to be 25% sweedish

Click to expand...

Yeah, most probably will 12 volts(and around) be the best voltage.

Today I was about to post correct OHM of an 226 W TEC. It would have been measured using AC current. But.... I didn't find the damn TEC this mornin, and I was so sure it'd be at the shelf!
I'll have to turn the house upside down tonite to find them !!!
I'll be back with thoose Ohms at saturday. I have to bike to work(a comfortable 9 miles in freezing weather) tomorrow and do the testing instead. HA !! I'll be milling some copper wb's aswell !!

Okay, you're 25% Swedish, cool! Then you probably know where Iraq is!! It seems like about 87% of the US ppl don't know where it is. Source: http://www.cnn.com/2002/EDUCATION/11/20/geography.quiz/index.html
I hope you all can live with me pulling your leg a bit

ookabooka said:

hmm. . . well my chip is 226 watt. . . I'll see if I can come up with a good mathmatical model for it, [edit: found out that Volts/Amps=Ohms].
If anyone knows if my resistance is good, plz tell me. thnx

Click to expand...

I have just recently found out that there can be a pretty big difference between OHM meter measurements and AC amps/AC Volt measurements.

I tried four different currents and all voltages pointed at a pretty fixed calculated ohm number. But this is for 80W TEC = 1,46 ohm.
When I used my Fluke 23 multimeter (a $100 instrument) I got 6 ohms... 5 ohms.... 11 ohms.... well.. I was holding the tec in the air by it's leads. If I barely touched the tec's surface with my hands it skyrocketed to 60+ ohms !!! and touching the other side gave -45 ohms ! and thats a really really light touch!
The accuracy will vary alot depending on the instument. I think that a cruder multimeter will do better, it might use higher voltage to measure hence making it less suceptible to TEC influencing the meter.

As for ookabookas measurements: If they are pretty steady no matter what you do to the surfaces I think the TEC is busted or atleast something fishy is going on. Also try to touch the tec with a finger on each side and on different spots, see if it affects the measurements and by how much.

Do check in here later today, I'll be off to work now and complete my ohm/seebeck measurements.

Well, by now I have measured the darn TECs resistance.

However... I was so damn dumb I forgot the papers at work !!!
I was so stressed to finish some Seebeck coefficient measurements, a pal was going to give me a lift home.

LOL! I made one seebeck measurement, in real haste, so it's not all that valid.

Anyway, I think (THINK!) I got about 5,5 mV volts from 10mA current = 0,55 Ohms.

226 W TEC has around 0,55 ohms... but this is just from the top of my head, so don't take it for 100% correct.