SAFE Regulated Power Supply

[BlueJello]

I'm looking at an 800W power supply that outputs 12 DC. I've found that you can convert computer PSUs to fit this purpose. My question is what is the difference between these two products? They both look very different, and one seems to be a Chinese knockoff PSU.

http://www.ebay.com/itm/HP-XW8400-C...991037?hash=item35faccc73d:g:8KkAAOSwDuJWukB8

http://www.ebay.com/itm/Fujitsu-A3C...212015?hash=item2a7546f92f:g:kOcAAOSwt5hYZDbV

My overall question is, which of these is safer to modify into a 12VDC 800W Power Supply. And if both of these are bad, are there better models than these, keeping within a $30-$40 range?

 

[Herschel Peeler]

I'm looking at an 800W power supply that outputs 12 DC. I've found that you can convert computer PSUs to fit this purpose. My question is what is the difference between these two products? They both look very different, and one seems to be a Chinese knockoff PSU.

http://www.ebay.com/itm/HP-XW8400-C...991037?hash=item35faccc73d:g:8KkAAOSwDuJWukB8

http://www.ebay.com/itm/Fujitsu-A3C...212015?hash=item2a7546f92f:g:kOcAAOSwt5hYZDbV

My overall question is, which of these is safer to modify into a 12VDC 800W Power Supply. And if both of these are bad, are there better models than these, keeping within a $30-$40 range?

I don't see any that look like 800 Watts. That is about 67 Amps at 12 V. Googling, they run about $200.

 

[BlueJello]

I don't see any that look like 800 Watts. That is about 67 Amps at 12 V.

The first one, when all the 12V positives and grounds are soldered together, it outputs the full 800W at 12V through those connections.

 

[Harald Kapp]

The first one, when all the 12V positives and grounds are soldered together, it outputs the full 800W at 12V through those connections.

800 W is the total power of the PSU. This doesn't necessarily mean that the full 800 W are available on one single rail (12 V). Typically this kind of PSU is designed to deliver the output power split among the several rails (12 V, 5 V). Drawing full power from only one rail may overload this rail, regardless of the number of wires you connect: within the PSU these all go to the same single output circuit.
You'll have to look up the specs of the PSU and check the max. current on the 12 V rail. Unfortunately this information is missing on the ebay offers (at least I can't find it easily).

 

[hevans1944]

Read the label on the power supply. There are four outputs, each with different current ratings. And the current ratings depend on the power rating from 800 watts to 1000 watts.

 

[BlueJello]

Read the label on the power supply. There are four outputs, each with different current ratings. And the current ratings depend on the power rating from 800 watts to 1000 watts.

This looks like it should work, can anybody confirm that this will function as an 800W 12V DC Power Supply?

 

[hevans1944]

Looks like it puts out 65.8 A at 12 V and 800 watts dissipation. That works out to 789,6 watts. Is that good enough for you?

 

[Colin Mitchell]

Buy a 12v car battery.

 

[Harald Kapp]

Buy a 12v car battery.

At 66 A the battery will be drained with ~ 1 hour, depending on capacity.

 

[BlueJello]

Buy a 12v car battery.

This is being used to power sensitive equipment and circuitry, not for running off of decaying voltage and temporary power.

 

[BlueJello]

Looks like it puts out 65.8 A at 12 V and 800 watts dissipation. That works out to 789,6 watts. Is that good enough for you?

Yes, I don't have much experience in regulated power supplies, I usually use much lower wattage or unregulated transformers. I just wanted to make sure before buying it.

 

[tedstruk]

first year electronics lesson 1.
There is no such thing as safe electricity.

 

[Harald Kapp]

There is no such thing as safe electricity.

... still most people die in their sleep...

That's no excuse.
Electricity has its risks, but you can minimize them by handling it as safe as possible. Or increase the risk by handling it in stupid ways.