Large power supply. / General Science and Electronics / Forums

Forums

4hv.org :: Forums :: General Science and Electronics

« Previous topic | Next topic »

Large power supply.

1 2 next

Move Thread

LAN_403

StormInABottle

Mon Feb 11 2013, 09:41PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

So i recently. blowed away all my power supplies. about 300$ into thin air :/ So i heard those atx power supplies are some tough bastards. So today i went to the shop . And for like 10 bucks. Got 3 dell atx power supplies. 2 1200 watts. and 1 1000 watts. Booth the same model. The 1200 watts one has 2 fans. So i figured. I only need the 12 volts rails. For 12 volts while using 1 psu. 24 while using 2. and 36 while using 3. Those babies spit like 50 amps each :) tho in theory. The suppy can supply 50 amps. But how much it actually supplies is how much the devices draws. For this i am using a zvs. But i will use it for many other things. But just for the mean time haha :3 btw those are new and un used. In theory. The black and the yellow wires are what i am after.

this is what i will follow. Also that green wire. that should go to a black wire. Should that black wire actually go with the rest? XD..? and also. i wont make any connectors like he did. just some ugly garbage. That the wires and clip them togeather. XD
So now the questions

1: should the black wire that the green wire gets connected to goes with the rest of the black wires.
2: When i put those in series. it is like. for simplicity sake. Each psu is +__- and a * means to wires are connected so.
+__-*+__-*+__-

So now i end with only 2 cables.
Sorry for these lame questions. I read that if that is done improperly that thing might start smoking and explode.. And i am a little scared :P. also is there a problem if the inputs are connected in parallel. and are all eating on one electric socket also. i wont run it grounded.

Houdini0118

Mon Feb 11 2013, 10:46PM

Registered Member #8558 Joined: Thu Dec 06 2012, 11:38PM
Location: usa
Posts: 57

yup server power supplys are even better for this though as they can have >100Amp 12v rails. Great fun with those. dont require a load to work ither. Although yours might need a 5v load idk it depends.

Shrad

Tue Feb 12 2013, 11:14AM

Registered Member #3215 Joined: Sun Sept 19 2010, 08:42PM
Location:
Posts: 780

get a used blade power supply which will provide 24V or even 48V at 50 amps

or get a VICOR FLATPAK power supply which will give the same performances plus you'll have some control over current for some models

TBJ

Tue Feb 12 2013, 12:01PM

Registered Member #5374 Joined: Mon Jun 18 2012, 06:54PM
Location:
Posts: 10

1) I'm not sure what you mean by "should the black wire go with the rest". The black wires are all commoned together inside the supply anyway, so it doesn't matter.

2) You can't connect the supplies in series. The black (ground) wire will usually be electrically connected to the power supply's case, and therefore to mains ground - so all the supplies will share a common ground and you will only succeed in shorting them out if you try to series them.

StormInABottle

Tue Feb 12 2013, 12:58PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

I will remove the ground then. And those can be expensive. Thats the only thing i found anyway. will post results

TBJ

Tue Feb 12 2013, 01:11PM

Registered Member #5374 Joined: Mon Jun 18 2012, 06:54PM
Location:
Posts: 10

I really wouldn't suggest removing the ground. The outputs can float at a pretty high voltage if you do.

...

Tue Feb 12 2013, 03:44PM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

Like others have said, it works fine to series them, you just need to unground all but one of the supplies. The easiest way to do this is to just break off the ground pin in the power connector, although if you do it this way the casings will all be at different voltages, so you will need to electrically isolate each of them. For a safer/more elegant solution you can take each one apart and remove all of the internal ground connections (there are usually several where the circuit board is bolted to the case, you can use a dremel, etc to cut the ground traces around the screw holes). You can also unground the entire stack to get a floating supply, just make sure that you have a ground somewhere in your circuit if you do this! It should also not be a problem to run all of them from the same electrical outlet, although if you want to run at full power you may overload the breaker (I am not sure what type out outlets you have an Andromeda, but in the US a normal outlet is only good for about 1800w with short runs up to 2500w before the breaker trips).

Just bundle all of the black wires for each supply, and all of the yellow wires for each supply, and then wire them in series. Often times server PSUs will have voltage sense lines that need to be dealt with, just bundle them in with their respective voltages (sometimes it is hard to figure out which is which, but luckly most server power supplies have the voltages labeled on the internal circuit board).

StormInABottle

Tue Feb 12 2013, 05:37PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

In Andromeda we run 2 ovens on one sockets and it is fine. The only limit though is the wire thickness. i have seen a 2300 watt heater. with some thin ass wire. Once i run that. The hell breaks loose. Wires burn the hell. And the usual boom.and the shop paying back meh monies :3 also. I have like 3-4 ungrounded sockets. just a classic 2.so how much would the volts be different. I mean. For the mean time. I will be running it on a zvs. pair of irfp250 half a watt 15 v zenners. 1n4007s. 2 watt 10k ohm resistors. 40 watts 490 ohm resistors. and some lame inductor. and some ceramic capacitors those few seem to not heat at all. the circuit is always cool. And at 12 volts i can melt my nice thick steel wire. alot more better that my past zvs.

Soo anyways. I get those nice un grounded sockets. And connect all inputs in parallel. tho i have a ground wire i made myself :D if grounding is that badly important i can ground the first one. but not the rest... Btw i found some expensive power supply that has plastic casing;. and some thick premium wires. Tho did not buy it.

StormInABottle

Tue Feb 12 2013, 05:43PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

oh i see i did not understand something. You were talking about the cases not the output. Well i am happy to tell you 2 things. in my experience with opening power supplies. THere is a ground wire that goes to a bolt and a nut on the circuit board. I can cut that. and a holy jolly lots of electrical tape :D also the original plan was that the supplies go in a box. also i can hack out the circuit boards. And put them with no chassis. And i remember when i was a child. Touching the psu of the running computer gave me a nice shock :3 there were usually sparks too :3 So current plans are like. Electrical tape on the chassis. And ofcourse cut out holes for the fans. am not a idiot lol. or cut off the ground wire off the actual input of the mains. By the way. for those interested i have booth 120 volts and 220. 2 in 1 :D also thanks for replies

StormInABottle

Tue Feb 12 2013, 08:58PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

I am now running 2. Had lots of fun. The power is so amazing. My zvs was never that strong. will run the 3 soon. Also for anyone thinking about buying some expensive transformers. Then no. Get a pc power supply. It will do all your needs. And more too.

1 2 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob