Extra Power Supply Needed????

[arcsecant]

I was just wondering why an most peltier setups use an extra powersupply.
I am thinking about doing a peltier setup, and I wish to keep the entire setup inside the case. However, I do not wish to have to PS's in my case (it definently will not fit). Is it possible to run a 156 Watt Peltier, and the other system compenents (2 hard drives, 1 dvd, 1 burner, and a few fans) off a Enermax EG651P-VE (651 Watt max)? The reason I'm asking is that a friend of mine has this PS, and would he would like to sell it to me for a good price. Looking at the max current and power ratings, it seems that the Enermax should be able to support this. The max output current rating for the Enermax's 12 V is 24A. I say the Peltier uses a max of 15 or 16A. So, that leaves 8A left on the 12V, is that enough to power the rest of the system? Am I calculating this correctly?

Thanks a lot!

 

[nmos]

FWIW I just looked at a Sparkle 250W PS and it supplies 8A on the 12V line.

 

[WarCon]

You would probably be ok.......24 amps should be able to supply all your 12volt needs and the peltier and have room to spare. Just make sure its not a lower rating on the nominal 12volts current and the max is 24 amps. If you run it over the nominal for long it....well you get the picture.....

Another suggestion......make sure you have adequate input airflow so enough air can move through the powersupply and isn't being drawn through other output fans. That kind of current will build significant heat in your supply.

 

[WarCon]

Sorry I forgot to add that your 156Watt peltier is most likely rated at 15volts. So if you figure your current at 12volts its really only around 10amps. Most supplies put out more voltage on the 12volt line so figure it at 12.5 for a good average and you will be using almost 11amps. So there should be plenty left.