DC Power Supply

Discussion in 'Livewell and Bait Tank Review' started by BKS72, Jul 20, 2009.

  1. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    My shad clean-out tank and my bait tank both use 12v livewell pumps for aeration and filtration. I have a regular 120v 100 gallon aquarium filter that I also use while they're in the garage. I wanted a stable DC power supply to be able to use the 12v pumps in the garage or to supply the pumps when they're sitting in the boat or truck in the driveway while I'm getting ready to go fishing.

    I had a couple spare computer power supplies lying around and as I tripped over one I had an idea. Since the supplies I had put out 12v, 5v, and 3.3v DC, I figured they would be just the ticket for what I wanted to do.

    I did a quick Google search and found a couple of articles on how to modify the power supplies over to become basically a bench power supply. A trip to Radio Shack, $5, and an hour later I was in business.

    The attached picture shows the power supply. Lots of different ways to manage your output connections, but I chose to leave the wires so I could add different connectors for different devices down the road. In the pic I'm using it to run my sonar so I can clean up my waypoints and tracks in the garage instead of the boat.

    Some notes of caution should you decide to do this (I am in no way recommending that you do, only explaining what I did:wink:):

    These supplies put out some current - the one in my pic is rated for 45A on the 5v side and 20A on the 12v side.

    Depending on the unit you use there are likely capacitors in the unit that will hold a significant charge after you unplug the power supply. Be very cautious when working inside the unit.

    As you can see from the picture, the cases on these units are very open to allow for cooling. Water and these things could lead to an unpleasant situation.
     

    Attached Files:

  2. catfishinsc

    catfishinsc New Member

    Messages:
    507
    State:
    SC
    I've been thinking about using a relatively inexpensive manual battery charger. Anybody ever tried this before?
     

  3. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    I have, but it's a hassle. The PC power supplies can be had generally a lot cheaper than a battery charger, that's why I went with it. That and it gave me an excuse to play in the garage for awhile:big_smile:
     
  4. catfishinsc

    catfishinsc New Member

    Messages:
    507
    State:
    SC
    Why was it a hassle?

    I'm thinking of putting on a cigarette lighter plug on it, that way I can just plug my 12V aerator into it. There's a 6 amp charger at northern for $30. Not many power supplies for less than that. Aerator only pulls around 2 amps I think. Basically no modification expect adding the plug, plus no extra wires to deal with. I wouldn't use it for anything but the aerator. I'm wanting to use it while we're not fishing when we spend the weekend at the lake so it doesn't drain the battery down. The battery charger would probably be a more portable solution for that.
     
  5. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    The hassle was my fault - I didn't put the cigarette lighter end on it because I still wanted to use it for a battery charger. Or if I had bait in the tank I couldn't take my charger and use it for charging a battery.

    Also, I already had the power supply lying around so the cost for me was just a sandbar resistor and a bit of solder (Tigerdirect has several new 400w supplies for less than $20, though). Another reason for me was the different output voltages and multiple output wires to support several different connectors and devices simultaneously. I think there might be a use down the road for charging something or using the 3.3 or 5v side to operate something that takes batteries as well.

    The battery charger idea should work fine, but I'm not sure what running it continually at 2 amps will do to the charger. I've had crappy luck with low-end chargers in the past so I was looking for a different alternative.

    I'm sure the charger will work fine for you, this was just a simple, quick, and cheap build that I already had 99% of the components lying around for.
     
    Last edited: Jul 20, 2009
  6. catfishinsc

    catfishinsc New Member

    Messages:
    507
    State:
    SC
    I found an even better solution:

    http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200326263_200326263

    I just happened to see them in the store today. I never saw them before because they were in a locked glass cabinet with solar panels. I never saw them on the web because they were under th alternative energy section.

    After scouring the web and finding nothing but items that don't output enough amperage or items that are way too expensive plus would need modification or other parts, I finally found a good solution that's ready to use out of the box. This is also more compact than the charger, plus it's in a more rugged case that doesn't have holes in it. And I'm going to test it tonight, but it's only supposed to output 12V, so I won't have to worry about the aerator overworking with the 14V from the charger.

    I guess now the charger will be a backup, or I'll just convert it back to clips and use it as a charger.
     
  7. catfishinsc

    catfishinsc New Member

    Messages:
    507
    State:
    SC
    After getting it home I realized it does have holes it for ventilation that I didn't notice before. I guess I can put a bucket over it to keep rain out. That was my main concern with the charger. Maybe "rugged" wasn't the right word either. Not sure what I was thinking there, but this will be easier to haul around and use.

    I did put the meter on it and it says it has 15V. I'm kind of disappointed about that but my dad says it probably will decrease under load, though I'm not sure how to test it.
     
  8. simpleokie

    simpleokie New Member

    Messages:
    148
    State:
    Okla.
    I've been hooking my aerator up to a bad battery, then hooking up a charger on 2 amp. It runs for several hours, then the charger kicks off and displays that the battery is bad. ThenI just take it off and put it back on again and the whole process repeats.I don't know if this is good for the charger or not, but I've been keeping 4 bullheads alive in my 5 gal tank for 3 days now all 4 have been on a hook too. Doubt it will work for shad but so far so good.
     
  9. catfishinsc

    catfishinsc New Member

    Messages:
    507
    State:
    SC
    That must be an automatic charger right? I don't know if a manual charger would kick off like that though. I wouldn't think it would since it is manual. I'm going to just use that converter though. I'll find out how it works this weekend.
     
  10. GaryF

    GaryF New Member

    Messages:
    3,649
    State:
    O.P., KS

    I wouldn't sweat the voltage, most devices are made with quite a bit of tolerance, boat electrical systems are all over the place with battery levels fluctuating and alternators causing spikes and increases. And your dad is right on about the voltage sagging under load.

    For what it's worth, that same adapter is available at Walmart for $22, look on the aisle where they have the Igloo coolers and stuff, as they sell it (Vector brand, but no doubt made in the same factory) for powering 12 volt coolers.
     
  11. simpleokie

    simpleokie New Member

    Messages:
    148
    State:
    Okla.
    yes it's an automatic charger, I'll probably use a converter too. I dont want to burn up my charger,I just haven't had a chance to go get one yet.
    These bull heads are tough. I doubt anything else would live like they are.