Question How many amps can I draw with a 400 watt PSU?

[wildjake4]

I'm currently trying to repurpose a 400-watt PSU into a power supply for this Peltier cloud chamber I'm creating, and was concerned as the Peltier coolers draw a maximum of 6 amps. I know one 12v+ cable can supply this with ease, but if I plan to use three coolers, that's well over what a wire can handle. I guess my primary question is, does each wire supply up to 12 amps, or is it the total amount of amps every single wire can produce?

I hope this makes sense, I'm not very good at wording it, but any help would be much appreciated!

 

[JeffreyP55]

I'm currently trying to repurpose a 400-watt PSU into a power supply for this Peltier cloud chamber I'm creating, and was concerned as the Peltier coolers draw a maximum of 6 amps. I know one 12v+ cable can supply this with ease, but if I plan to use three coolers, that's well over what a wire can handle. I guess my primary question is, does each wire supply up to 12 amps, or is it the total amount of amps every single wire can produce?

I hope this makes sense, I'm not very good at wording it, but any help would be much appreciated!

Ohms law I=W/E. What voltage(e) are you looking at? Or since you hsve 2 varibles of E and I, (E)I.

 

[kanewolf]

I'm currently trying to repurpose a 400-watt PSU into a power supply for this Peltier cloud chamber I'm creating, and was concerned as the Peltier coolers draw a maximum of 6 amps. I know one 12v+ cable can supply this with ease, but if I plan to use three coolers, that's well over what a wire can handle. I guess my primary question is, does each wire supply up to 12 amps, or is it the total amount of amps every single wire can produce?

I hope this makes sense, I'm not very good at wording it, but any help would be much appreciated!

Every power supply has a sticker identifying how many amps a particular feed can provide.
Your "400 watt" power supply might be a $15 piece of junk which will catch fire with 10A. Or it could be a quality power supply and provide 20A.
After that it is a question of wire gauge and distance.

 

[JeffreyP55]

Every power supply has a sticker identifying how many amps a particular feed can provide.
Your "400 watt" power supply might be a $15 piece of junk which will catch fire with 10A. Or it could be a quality power supply and provide 20A.
After that it is a question of wire gauge and distance.

Most newer supplies do but not all. Especially if they are ancient in computer years. Thought maybe the OP would like to tinker a bit.

 

[USAFRet]

Most newer supplies do but not all. Especially if they are ancient in computer years. Thought maybe the OP would like to tinker a bit.

If they are ancient enough or crappy enough to NOT have a sticker (even if a falsified sticker), then it absolutely should not be used. For anything.

Thought maybe the OP would like to tinker a bit.

sniff sniff...I smell smoke.

 

[hotaru.hino]

Most newer supplies do but not all. Especially if they are ancient in computer years. Thought maybe the OP would like to tinker a bit.

Looked up a few labels for "ancient" computer's power supplies, such as the IBM 5150 and Commodore 64.

They state their output characteristics. Heck I'm pretty sure it's been a requirement since forever for discrete power supplies to state their characteristics so that the average person doesn't, you know, blow something up.

 

[JeffreyP55]

Looked up a few labels for "ancient" computer's power supplies, such as the IBM 5150 and Commodore 64.

They state their output characteristics. Heck I'm pretty sure it's been a requirement since forever for discrete power supplies to state their characteristics so that the average person doesn't, you know, blow something up.

I said computer years not people years. Would it fill your need to run a 5th gen i5 and GTX 980?

 

[JeffreyP55]

If they are ancient enough or crappy enough to NOT have a sticker (even if a falsified sticker), then it absolutely should not be used. For anything.


sniff sniff...I smell smoke.

Since the OP never specified the brand or year of manufacturing, We don't know if it is a gem or piece of crap. People love removing stickers to make things look purdy..

 

[CountMike]

For projects like that it's better to make own, all you need is a transformer and a rectifier bridge (and eventually large capacitor). A bit fancier would be a battery charger

 

[geofelt]

Post a photo of the psu data plate.
Some old 400w units delivered most of the power ar 3.3 and 5.5v, not at 12v which is what you seem to be wanting.

Also, cheap units may only deliver advertised power at room temperatures.