Results 1 to 4 of 4

Thread: Q regarding 12V DC-DC adapters

  1. #1
    Newbie jaytyn's Avatar
    Join Date
    Oct 2005
    Location
    Melbourne Australia
    Posts
    30

    Q regarding 12V DC-DC adapters

    Hi

    I am using the power supply below:


    This power supply will work OK when connected to the internal car ciggy lighter,

    But I also have a cig lighter output in the boot that I wired directly to the battery (+ terminal) and the negative to ground. (Fused of course). When plugged into the boot cig lighter, the adapter power light comes on, but will not power the laptop. It eventually blew the adapters fuse.
    here are the specs of the adapter:

    Vibration Input Voltage Range
    DC11V-16V

    Input Rated Current 7AMP

    Input Min. Current 100mA
    Input Power 88W

    Efficiency
    >88%(TYP)

    Output voltage:16V/18V/19V/20V(-0.4/+0.5V@4A LOAD)

    Output current:
    DC16V-20V 4AMP(max)

    Why would it work OK on the car cig lighter, but not work and blow fuses from the boot cig lighter?

    THanks
    Jayt

  2. #2
    Admin. Linux loser.
    Auto Apps:loading...
    Bugbyte's Avatar
    Join Date
    Sep 2004
    Location
    Corning, NY
    Posts
    7,364
    Blog Entries
    2
    There is a voltage drop that can be an issue with longer wires. What gauge wire did you run to the back and what is the total wattage you are drawing on your system?
    Quote Originally Posted by ghettocruzer View Post
    I was gung ho on building a PC [until] just recently. However, between my new phone having internet and GPS and all...and this kit...Im starting to have trouble justfiying it haha.
    Want to:
    -Find out about the new iBug iPad install?
    -Find out about carPC's in just 5 minutes? View the Car PC 101 video

  3. #3
    Newbie jaytyn's Avatar
    Join Date
    Oct 2005
    Location
    Melbourne Australia
    Posts
    30
    Thanks for your reply...

    I was starting to get suspicion it may be due to current/voltage loss from the cable length.

    I am not entirely sure on the gauge of the wire. Its medium grade automotive figure-8 cable.

    The voltage with engine OFF is 12.52 V
    With the engine OFF it is 14.45 V

    I am not really draining much current, the laptop adaptor only draws a MAX of 7A, and has a 5A fuse in it...

  4. #4
    Admin. Linux loser.
    Auto Apps:loading...
    Bugbyte's Avatar
    Join Date
    Sep 2004
    Location
    Corning, NY
    Posts
    7,364
    Blog Entries
    2
    Are you certain that you haven't reversed thepolarity of your wire? Check it again with a multimeter to confirm that it is the same as the lighter in the front.

    Otherwise, I'd think it was due to voltage loss.

    BTW, you meant that your voltage with the engine ON was 14.45, right?

    Have you tried booting the laptop with the engine on?
    Quote Originally Posted by ghettocruzer View Post
    I was gung ho on building a PC [until] just recently. However, between my new phone having internet and GPS and all...and this kit...Im starting to have trouble justfiying it haha.
    Want to:
    -Find out about the new iBug iPad install?
    -Find out about carPC's in just 5 minutes? View the Car PC 101 video

Similar Threads

  1. Pinout Color Codes / Tables
    By gummybear in forum General Hardware Discussion
    Replies: 4
    Last Post: 05-12-2005, 03:05 AM
  2. 12v DC to 5v DC @1.5 amp converter-Hardwire
    By DirtyDieselPhil in forum Power Supplies
    Replies: 1
    Last Post: 04-12-2005, 10:17 AM
  3. Power Supply 12v Dc regulator Help
    By niralthegreat in forum Power Supplies
    Replies: 9
    Last Post: 02-26-2005, 06:04 AM
  4. How to change 12V DC to 6?
    By Skipjacks in forum Power Supplies
    Replies: 6
    Last Post: 12-12-2004, 11:35 PM
  5. Replies: 5
    Last Post: 08-20-2002, 08:32 PM

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
  •