Results 1 to 5 of 5

Thread: laptop PSU for garage power

  1. #1
    Variable Bitrate Grrrmachine's Avatar
    Join Date
    Sep 2005
    Location
    Warsaw, Poland
    Posts
    346

    laptop PSU for garage power

    I'll be stripping out my system to fit into a new car next month, and I'm toying with the idea of fitting a barrel connector to the wiring so that I can run it with a 12V 10A laptop-style power brick whilst in the garage.

    The current system uses an Opus 150W in the standard wiring config (ground, hot 12V and IGN from the ignition), and I'd like to save the battery whilst doing installs. I've got two dilemmas though:

    1) if I just make a parallel wire from the hot 12V and ground to make a barrel connector plug, will I damage the car's battery?

    2) can anyone figure out the wiring so that it also feeds the IGN line? I don't really want to add any more switches (flicking between power sources), but on the other hand I'm worried that leaving the car with the ignition on (engine not running) could also drain the battery.

    Anyone else tried this, or see the problems, before I shell out 25 quid for the power block?

  2. #2
    Maximum Bitrate FusionFanatic's Avatar
    Join Date
    May 2007
    Location
    Boston
    Posts
    791
    Quote Originally Posted by Grrrmachine View Post
    I'll be stripping out my system to fit into a new car next month, and I'm toying with the idea of fitting a barrel connector to the wiring so that I can run it with a 12V 10A laptop-style power brick whilst in the garage.
    good luck finding a 12vdc@10A power brick. 5A is usually the most you'll find.

    Quote Originally Posted by Grrrmachine View Post
    The current system uses an Opus 150W in the standard wiring config (ground, hot 12V and IGN from the ignition)
    a 150W PSU will draw ~13A at full load, so even if you could find a 10A "laptop style" power brick, it may not be able to provide enough "juice" for your system.

    Quote Originally Posted by Grrrmachine View Post
    if I just make a parallel wire from the hot 12V and ground to make a barrel connector plug, will I damage the car's battery?
    it won't damage the car battery, but it will try to charge it. it may try to pull too much power from it which could create a fire hazard. so I wouldn't recommend it.

    your barrel plug idea will work fine for powering the carputer (as long as the barrel plug/jack can handle the current), but it should not be wired parallel to the car battery. you should disconnect the car battery wires or wire a switch to select between power sources.

    Quote Originally Posted by Grrrmachine View Post
    can anyone figure out the wiring so that it also feeds the IGN line? I don't really want to add any more switches (flicking between power sources)
    if you don't want to add a switch, then you'll have to manually disconnect/reconnect your power wires when switching between power sources.

    another option is to wire a relay (or relays) to automatically switch to the "power brick" input when power is connected to your barrel plug.

    the bottom line is; it's more work then necessary... if you plan on running your carPC for a couple hours while the engine is off, then hook up a battery charger to your car battery.

  3. #3
    Variable Bitrate billmee's Avatar
    Join Date
    May 2005
    Location
    USA
    Posts
    299
    Quote Originally Posted by Grrrmachine View Post
    I'll be stripping out my system to fit into a new car next month, and I'm toying with the idea of fitting a barrel connector to the wiring so that I can run it with a 12V 10A laptop-style power brick whilst in the garage.
    Another option is to put a battery charger on the car's battery while using the pc.

    Just measure the current going to the pc and get a charger rated to more than that value.

    Example : my pc uses ~6 amps at 12 volts and my charger can supply 10 amps ( at 14.?volts ) so my battery never sees the load.

  4. #4
    ptk
    ptk is offline
    Variable Bitrate
    Join Date
    Apr 2004
    Location
    Singapore
    Posts
    333
    using car batter charger is a good idea.
    i use bench 12v supply at home.
    ***
    CarPC Ver 4 completed. Aopen i45GMT-HD, C2D mobile 2GHz. Photofast 64GB SSD. Novatel EU-850D

  5. #5
    Variable Bitrate Grrrmachine's Avatar
    Join Date
    Sep 2005
    Location
    Warsaw, Poland
    Posts
    346
    Thanks for the above suggestions, it seems that it might just be simpler tu use the car battery charger because of the thickness of the cables.

    As for the wattage, I run the PC on a 10A fuse at the moment, so it definitely draws less than that. For anyone else wanting to try the powerbrick option, they're certainly available:

    Sorry though, it's in Polish

Similar Threads

  1. FAQ: How do I power my DC-DC PSU on my workbench?
    By DarquePervert in forum The FAQ Emporium
    Replies: 57
    Last Post: 12-14-2011, 06:55 PM
  2. FAQ: Will <insert PSU model> Power Supply work with my system?
    By DarquePervert in forum The FAQ Emporium
    Replies: 9
    Last Post: 10-10-2006, 12:38 PM
  3. Power up front (laptop in back)
    By pshadwick in forum Laptops, Netbooks, Tablets, UMPCs, etc.
    Replies: 6
    Last Post: 02-09-2006, 04:25 PM
  4. Wanna power this laptop since I fried my system today.
    By MikeHunt79 in forum Power Supplies
    Replies: 6
    Last Post: 07-07-2003, 11:24 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •