What do you guys think of these power supplies?
 

Take a gander: http://www.rcgroups.com/forums/showt...light=hyperion

I am picking up a 46amp model. I have 2 610i, a 1210i, 1 5i and a 2 amp hextronic to run off it. I figure 46amps should do for the lot...

As you have probably seen on TV Circuit City is closing, if there is one near you go ask them if they have any of the PS from the car audio displays since they are selling displays too.
I got a 13.8V 37.5A cont with 50A peaks for $30 and it work perfectly:intello:

Those car audio PS units are usually linear, which means big, heavy, and inefficient. But if the price is right...

What do the ones in the link look like to you, BG? Decent, crap??? I have no idea about this stuff...

I agree. I've got a big Astron 57A continuous PS sitting at home. It's only about 46lbs and about 14" x 14" x 8".

Can't really say. Those are definitely switching PS units from the few pics I looked at, and they have decently sized components, but that doesn't necessarily mean a good PS. I'd have to hook it up under different loads and see how it performs to tell for sure. Can't see line/load regulation, ripple voltage, temperature, etc from pics. :wink:

Ok, was not sure if you were familiar with server P/S like that. You seem to be more knowledgeable about computers than I (my dog is more knowledgeable than I actually).

Would this pic help any? I am guessing that depending how it is wired it can provide different voltages?

http://i206.photobucket.com/albums/b...imp/mis885.jpg

I dont like to use computer PSs mostly due to that you are starting with a 12v output and it will drop to around 10vs when in use...I think the Hobby Lobby PSs are the best bang for the buck

i would like to know also because my buddy would like to run a duo and a 989 and prolly a another small charger all at once, and i wouldnt mind having one also

I was wondering the same thing. I somewhat read the details of modding a computer PS a while back. Seemed like you had to do something to them to ensure that they would not drop voltage too much under load.

With the 46amp model I must assume that it holds voltage pretty well under load. I do not usually use more than 1 of my 5 chargers at a time, and if i do it is to slow charge single lipo cells, or multiple small packs...

I may give one a try, the price is decent...

I too have an issue with a computer PS being at exactly 12v. Not only does this not give you much voltage leeway before it dips too far shutting off the charger, but the lower voltage will require more current to charge a specific pack than it would at say, 14v.

However, depending on the design on the PS unit, you can usually do "stuff" to boost the voltage a bit. I've seen one of three ways to do this:

1) Load down one of the other (3.3v or 5v) rails. All three supplies (12, 3.3, 5v) are all fed from a single main transformer. So, if one is loaded down, all three voltages usually drop. But, one of those rails contains a feedback circuit (usually a coil) that tries to compensate and boost the voltage back up. Unfortunately, there is no standard to which one that is, so you have to experiment and see which rail needs to be loaded.

2) Sometimes, there is a little adjustment potentiometer inside the PS where you can make fine adjustments. I've been able to squeeze out ~13.8v adjusting this. But, you can't assume that the presence of a pot does this - it might adjust something totally different. So, again, you have to experiment; put a meter on the output and make small adjustments. If the output doesn't change, set it back.

3) Some units have a smaller gauge feedback wire that attaches to the main wire it's monitoring at the very end of the main wire. The purpose of this is to detect a voltage drop along the wire (due to high currents) and boost the output until this sense wire sees the proper voltage. However, you can sometimes "trick" the sense wire with a simple voltage divider circuit or similar so that it sees ~1-2v lower than there actually is, which causes the regulator to boost the output accordingly. I've done this on an Antec TruePower 330w computer PS with very good results.

No matter what, you have to experiment. And doing so can be dangerous since there are hazardous voltages in there. Most switchers rectify 120v AC into 180vDC and then use a high speed switching circuit to get the output you want. May seem complex, but the size, weight, and efficiency are much better because of the higher frequency (instead of the low 50/60Hz).

Ok, so my best bet is to get some really good pics of the PS internals and post them on here...

Regular PC PSUs can be kinda cheesy sometimes when it comes to output regulation. I would ASSUME that a server PSU would have much better regulation, since a server needs to be very reliable when it is run 24/7 and at higher loads than a PC.

Can you find a data sheet for that PSU? It should specify what the output tolerance is.

Another question, I am guessing it does not matter which way a PS sits... I plan to mount the thing to the wall with the fan pointing down to keep the dust out of it...

Nope. Doesn't matter. That's a good idea, actually. :yes:

I've got the 30 amp model and it won't quite do 25 amps. I paid $20 for it.

Interesting, I found the larger model cheaper than he sells them. I may give it a try... If it only does 30 amps it will still be more potent than what I have now...

Ok, so I just won the 46amp unit on ebay for 23.99 shipped... Saved a few bucks. I will get some pics of it up here when I receive it.

That's ridiculous. How did you test it? At that price I'd think it was defective.

I have 2 computer ps that I made 1 is 8amp and the other is 9amp. The large one will only do my 4 and 5s packs..it sends an error on smaller packs. The 8amp one will do it all no sweat. I am looking into a larger one so I can do 2 5s packs at once.

I actually bought one from a co...I won't mention who, it was a 35a 500w supply...perfect, right! There was an error at the warehouse as far as the stock # goes and after sending 3 BACK I basically told them to **** off. I went so far as to take a picture of the one I wanted w/all the technical info on it...I sent it in and they still got it wrong!

Here is one I was considering
http://www.newegg.com/Product/Produc...82E16817339024

http://www.newegg.com/Product/ShowIm...Power%20Supply


Not bad 30a and 650w

An even bigger one..52 a and 650w

http://www.newegg.com/Product/Produc...82E16817139005

I used my cba to pull current thru it increasing until it finally kicked off. Backed it down and then increased. I thik it was 25 amps or so. I know I wrote it down, would have to go look it up.

I think it was supposed to be a 360 watt, but wrote 300 useable watts on the box. It did a nice job of maintaining voltage. I figured for $20 it was still a decent deal.

I would say so, 20 bucks sounds good to me. Hopefully the unit I just bought will work. I can sell my other power supply, and free up some room on the bench...

This one is SWEET
http://www.newegg.com/Product/Produc...82E16817153070

I used an earlier revision of this unit to build a supply a while ago. Preformed well. steady 12v due to the usage for the higher end video cards. This ones a little much but its like a 60a total output on this power supply.

That one has two 12v rails, so each one probably has around half the total. I kinda like the 52A model posted above by magman (http://www.newegg.com/Product/Produc...82E16817139005) because it is a single rail supply. In either case, I would definitely open it up and replace the small wire bundles with 12GA or 10GA wire soldered directly to the PCB. I wonder what kind of tricks can be done to these to boost the 12v to something closer to 14v?

Years ago I had a Rivergate 30 amp power supply. At that time it was said they were the best for our use in the hobby. They're a bit pricey compared to others you can find on the web but I have never heard of anyone who used them not absolutely love them.

http://www.rivergatedist.com/PowerSupply.htm

BrianG maybe you can chime in on them if you know about them.

So they mislabeled the box?

I don't personally have experience with them, but they look really nice. And the capability to set them to 14.2v is really nice too. As you know, a little extra voltage reduces the current required for a given power draw (10A @ 12v is the same as 8.45A @ 14.2v).

If I was gonna get one, I'd get the 90A model: http://www.rivergatedist.com/bulldog_90.htm It would be nice to have one supply at the track to feed several chargers at once. One large PS is gonna be more efficient than several smaller ones usually. Actually, it would be nice for the larger tracks to have a couple of these on-hand.

This comment in that linked page is funny: "if you need more power than this buy a welder". :yes:

Looks aren't everything, but you can get a pretty good indication of whether the supply will handle what it is spec'd at from looking at the guts. Large capacity filter caps, large gauge wire on the transformer/coils, large heatsink (even at 80% eff, the heatsink will need to dissipate some power and you can extrapolate some data merely by size), and transistors/FETs that will deliver (according to datasheet). Of course, a company could use adequate looking parts and not deliver the performance, but it wouldn't make much sense to go to the expense of using beefy parts and cheap out at the end.