Power Supply for a Hobby Charger

[dlong]

Does anyone know if you can use a PC power supply for a Hobby Chargers? Something like of of these:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139026&Tpk=N82E16817139026

?

Assuming, of course, the hobby charger takes 12V as input.

Thanks,

-d

 

[spencer]

Yes you can but you need to modify it first.

This is mine right now. Full size.

I took it apart, and soldered the corresponding wires to the binding posts. There is a power switch on the side (you can see it by the power cord). The + jack is either 5V or 3.3V depending on where the top switch is. This setup allows for a connection between 12V and 3.3V to give 8.7V and similarly for 5V, 7V. There are several guides on the internet on how to accomplish this conversion.

I recommend trying to find a used power supply locally as you can usually get more for your money. I paid $10 for this charger. It will do 32A @ 12V for 385W. Doing this conversion to a new charger will certainly void the warranty.

 

[dlong]

Why open it up and solder? Couldn't you just connect the wires to the 12V molex (/pins/plugs/or whatever they are) and use that?

 

[spencer]

Putting the binding posts on allows for the use of more power. You can't pull very much current through the 20 gauge (or whatever they are) wires.

Also, this setup is extremely modular now. The binding posts use a standard 4mm connector. I can plug almost anything into them. When ever I hook anything up it is extremely easy and SAFE. I don't know what you had planned but trying to tie into one of those connectors sounds like a pain in the *** and potentially dangerous if you don't have the female adapter.

In my opinion, hobby chargers should be hooked up properly using wire that can handle the current, as well as appropriate connectors. Almost every hobby power supply has these connectors on it. If you are going to do something do it right. Don't compromise safety to save a few dollars. If you don't feel you are technically capable of a conversion project like this, buy something pre-made.

 

[dlong]

I was going to cut the head off the connector, solder the wires to banana binding posts, shrink wrap the wires and use it that way.

BTW, the current price of the listed PS is $20/AR with shoprunner's free shipping. So it's not too bad (32A, 12V up to 430W) and with Active PFC. Although, I'm not sure it really makes that much of a difference or if it has any effect when used as a PS for a hobby charger.

I also have a few DELL laptop bricks except the voltage out of them are all 19.5V, 4.2A, 90W .... I don't think any of the chargers takes 19.5V and I'm not totally sure if 4.2A is enough ...

-d

 

[spencer]

Well it at least sounds like you are going to be doing it properly. Having said that, if you are going to be putting binding posts anyway, it isn't that much harder to go the extra mile.

Some power supplies will not stay on unless there is a load attached. I got lucky and mine works without a load. I think the new ones need a load to stay on. The advantages of doing it the way I did is that it facilitates a power switch, and if you need a resistor, it fits inside (see this guide).

 

[spencer]

Looking around it appears you can buy breakout boards for a non destructive alternative.

Here.

 

[sunny_nites]

I've been using the power supply from a HP laptop PC that had the correct voltage and current capacity. Works great. I have never gotten around to matching up the jacks, I just use the alligator clips and jack adapter that came with the charger to connect to the power supply.

 

[N8N]

Rather than that I would probably look on Craigslist or something for a power supply intended for use by a CB or Ham hobbyist. I have one and it is useful for so many things. I *used* to have a regulated adjustable electronics lab power supply salvaged from the trash at college, but it was too big to keep moving around :/ But I don't see why the PC supply wouldn't work until you find one cheap.

 

[m4a1usr]

Get a server power supply off Ebay. You can get a 12v 45 amp (or more!) power supply for less than $30. There are herds of them. Just do a little research using google and with some simple mod's you will have a power supply far more than you will ever need.

 

[BVH]

Get a server power supply off Ebay. You can get a 12v 45 amp (or more!) power supply for less than $30. There are herds of them. Just do a little research using google and with some simple mod's you will have a power supply far more than you will ever need.

These are great and work well and many can be serial'd or parallel'd for higher output. But many don't have the 5V and 3V outputs so if you need that Voltage, many of these wont work.