dpaton

Switching power supplies generally run very near the edge of the safe operating area of the capacitors used in them. If the specs are off, or the cap is a bum part, they'll fry. Not always immediately either. Same thing if the temp rating of the cap is too low, when the cap starts dissipating heat under load, it'll overheat and outgass, then short, and POP. Sometimes it takes a while for a bum part to show it's stripes. ICs are famous for it. They'll get zapped with static, and still work under normal circumstances, but as soon as you try to use them near the edge of their performance, they malfunction or break or both.

Off the top of my head, I'm guessing the failure chain went like this:

1. Marginal cap gets installed
2. PS passes power-on and short term light load tests
3. Unit ships
4. End user tried it out, it works
5. PS actually gets USED, and cap becomes more marginal
6. Repeat (5) until failure.

I've seen it before in power supplies, amplifiers, computers, and stuff I've built myself. Like death and taxes, it's an unfortunate side effect of life in the real world. :-(

-dave

True R/C Racing

if i get a new one. should i put a Fan? is it needed?

True R/C Racing

what voltage setting do you guys have it? Im charging one charger right now 6 amps and i am gettin a new one so will be 2 charger 6 amp Soon. Do you change the voltage setting if You have one or two Chargers? Need Tips

JusBox

iTrader: (1)

A fan wouldn't hurt but i don't think it's necessary. I wouldn't mess with the voltage, it should be fine the way it is but you can always check with a voltmeter and adjust if you need to.

dpaton

he votage should be fine without any adjustment as long as you keep your power leads nice and fat. The regulation on those supplies should be good for something like +/-0.05V up to their rated output.

Also, if you do adjustthe volatge of the supply, I'd stay away form cranking it all the way up to get 14.5 or anything like that. It'll work, but the stress on the supply will be increased, and from what I've been seeing, these supplies aren't designed with a ton of headroom for things like that.

A fan is probably a good idea if you're running it at more than 75% of it'srated capacity, ie, more than ~7A on a 10A supply.

As always, my $0.0125 ($0.02 minus taxes, etc)

-dave

etzkev

Dpaton, this is directed toward you, but if anyone else has the answer, please let me know!

How can I wire my two Cosel power supplies together to combine the Amp Outputs, but not raise the voltage? I just want to keep the voltage at around 13.8, but instead of having two power supplies that each put out 13 amps, I want to combine them (somehow ) to get a total of a 26 amp output.

Thanks in advance,
Kevin

True R/C Racing

13.6 /2= 6.8 So put at 6.8 and Put together will add up to 12.6 Be smart Etzkev

Super Steve

iTrader: (9)

er... what are you talking about?

etzkev,
Put the + outputs together and the - outputs together.

This should give you the same voltage but will give you combined amp...

This may not be recommended though...

rough512

iTrader: (12)

do you really need the combined amperage?

If you're using only 13 amps at any time then use just one. It's more efficient.

I'm not familiar with your power supplies. Usually if you put two supplies in parallel, do not expect to use the total output at all. Care must be taken to prevent either power supply from exceeding its maximum rating. Differences in component tolerance, internal resistances etc will always cause one of the supplies to work harder than the other.

If you really need the combined amperage, I recommend you insert current dividing resistors to distribute the load on the two PS. You will need high pwer, low ohm resistors preferably with attached heatsinks. Connect one resistor end to the + side of one pwr supply. Do the same with the other resistor and pwer supply. Connect the two ends of the resistors together. You may now use this as your new + terminal. Connect the two - PS terminals and use it as the Negative terminal.

etzkev

What are you talking about?! Be smart Ariel! Each power supply is 13 Amps, and combining them will make a 26 Amp power supply.

etzkev

Yeah, I went ahead and put them together before with my electrical knowledge, and luckily, I did everything right! Now I have a 26 Amp power supply. I just connected the outputs together and connected the inputs together, and everything is great!

Scrad

iTrader: (16)

You can adjust the voltage screw and take some of the voltage out if you are still worried about having to many volts.

etzkev

Haha, I knew that! I just wanted to make sure I didn't wire them together so I wouldn't get a combined voltage.