Results 1 to 10 of 10

Thread: Simple M1-ATX question

  1. #1
    Newbie
    Join Date
    Mar 2005
    Posts
    46

    Simple M1-ATX question

    Ok just a quick question about my m1 atx. I'm trying to find a good source for my + wire to go to without running wire to my battery. Between drilling and ripping my interior apart to cover wires and the freezing cold weather it just doesnt seem worth it, though i may be wrong

    I know its probably not a good idea to wire it to a cigarette lighter due to the fluctuation in power (i did my searching ) so i was contemplating wiring it to the same power line that my headunit hooks up to. Is this a bad idea? if so where else would be good? my ignition line will be going to the ignition fuse and ground will be about 6 inches from the psu

    thanks

  2. #2
    Newbie
    Join Date
    Mar 2005
    Posts
    46
    to the top

  3. #3
    Maximum Bitrate crooper's Avatar
    Join Date
    Nov 2006
    Location
    Everett, WA
    Posts
    467
    I definitely understand the cold part... I've put off working on my CarPC for that exact reason (20 degrees tonight... brrr).

    You shouldn't have to drill for an 8 gauge wire, there are usually places in the firewall that it'll fit through (search around a bit). I don't believe there are any other wires in the car that are thick enough to carry that kind of amp load. Am I right guys? The stock +12v lead to my car stereo was like 24 gauge.

  4. #4
    Fusion Brain Creator 2k1Toaster's Avatar
    Join Date
    Mar 2006
    Location
    Colorado, but Canadian!
    Posts
    10,053
    Quote Originally Posted by crooper View Post
    I definitely understand the cold part... I've put off working on my CarPC for that exact reason (20 degrees tonight... brrr).

    You shouldn't have to drill for an 8 gauge wire, there are usually places in the firewall that it'll fit through (search around a bit). I don't believe there are any other wires in the car that are thick enough to carry that kind of amp load. Am I right guys? The stock +12v lead to my car stereo was like 24 gauge.
    You are correct. The HU wire harness is puny, and the cig lighter is a bad idea not because of power fluctuations, but because again it is really tiny wire and not made to handle that kind of amperage.

    I was in my garage in -5F weather 2 weeks ago drilling a hole for a second 4awg wire to the battery. Damn it was cold, but butter to freeze my *** of and do it right, then do it wrong and light my car on fire.

    And yes for 8awg wire there should be ample room in the firewall already so simple procedure. Or to be ghetto run it through your door frame. j/k. Don't do that!

    Make sure to fuse it.
    Fusion Brain Version 6 Released!
    1.9in x 2.9in -- 47mm x 73mm
    30 Digital Outputs -- Directly drive a relay
    15 Analogue Inputs -- Read sensors like temperature, light, distance, acceleration, and more
    Buy now in the MP3Car.com Store

  5. #5
    Newbie
    Join Date
    Mar 2005
    Posts
    46
    well i bought my psu used from a member on here and the + - and ignition wires to it are only 18 gauge, should that be right or what? i guess ill run 8 gauge to the battery and fuse that, run the - to a bare metal piece somewhere close to the psu and run the ignition to a fuse...another question about the ignition. any suggestion as to what fuse to link it to? on my old car i had it linked to a 7 amp blinker fuse but i dont think that something that small will be powerful enough to handle the engine cranks and stuff...let me know

  6. #6
    Fusion Brain Creator 2k1Toaster's Avatar
    Join Date
    Mar 2006
    Location
    Colorado, but Canadian!
    Posts
    10,053
    the small guage wire is fine for small distances. so yes.

    the ignition wire draws almost nothing. milliamps. it is just an indicato rof whether your car is on or off. the actual power comes from the wire you are running to he battery.
    Fusion Brain Version 6 Released!
    1.9in x 2.9in -- 47mm x 73mm
    30 Digital Outputs -- Directly drive a relay
    15 Analogue Inputs -- Read sensors like temperature, light, distance, acceleration, and more
    Buy now in the MP3Car.com Store

  7. #7
    Newbie
    Join Date
    Mar 2005
    Posts
    46
    so as opposed to running the ignition wire to a fuse could i wire that to a cigarette lighter line? they only get power when the car is on and since the ignition source only draws a few milliamps it should be able to handle that correct?

  8. #8
    Fusion Brain Creator 2k1Toaster's Avatar
    Join Date
    Mar 2006
    Location
    Colorado, but Canadian!
    Posts
    10,053
    Quote Originally Posted by timdastis View Post
    so as opposed to running the ignition wire to a fuse could i wire that to a cigarette lighter line? they only get power when the car is on and since the ignition source only draws a few milliamps it should be able to handle that correct?
    Yes that should be fine. The ignition wire on the cig lighter is fine.

    The main power however must be on a good power line, and on cars you are going to have to make a good line by running a wire to your battery. I was hesitant at first, but believe me It was worth it in the end.
    Fusion Brain Version 6 Released!
    1.9in x 2.9in -- 47mm x 73mm
    30 Digital Outputs -- Directly drive a relay
    15 Analogue Inputs -- Read sensors like temperature, light, distance, acceleration, and more
    Buy now in the MP3Car.com Store

  9. #9
    Fusion Brain Creator 2k1Toaster's Avatar
    Join Date
    Mar 2006
    Location
    Colorado, but Canadian!
    Posts
    10,053
    And I don't know what kind of car you have, but on my honda, the center console had a nice area to hide wires along with the trim panels on either side.
    Fusion Brain Version 6 Released!
    1.9in x 2.9in -- 47mm x 73mm
    30 Digital Outputs -- Directly drive a relay
    15 Analogue Inputs -- Read sensors like temperature, light, distance, acceleration, and more
    Buy now in the MP3Car.com Store

  10. #10
    Low Bitrate
    Join Date
    Aug 2006
    Location
    Nottingham, UK
    Posts
    98

    Post

    An additional note, some PSUs don't just use the ignition line as a turn-on signal.

    My M1-ATX needs a decent amount of current on the igniton input.

    If yours is the same its not much more work...

    • Run a thin(ish) wire back from the cigar lighter as you plan
    • Split your 8gauge cable from the battery (with a distro bock or something) into two feeds (say 16gauge).
    • One feed can be the 'always on' PC terminal
    • The other can go to the PC's ignition terminal. Then cut this wire in half and stick a relay inbetween it (automotive relays are cheap and easy!)
    • Finally the cigar lighter wire needs to be connected to the low input of the relay. You'll also need a simiarly thin wire to ground the relay.

    This way. You turn your ignition. A tiny current from the cigar lighter flicks the relay on. Your PC gets all the current it needs from the battery feed.

    Also, if you are going to add audio amps etc you can use the distroblock to provide always-on feeds for them. Might need to use lower gauge cable though.

    Andy

    PS - Its a good idea to ground all your things to the same ground point.[/LIST]

    Then just fix the cigar lighter wire to the relay aswell.
    -------------------------
    What's that burning smell?
    -------------------------

Similar Threads

  1. do oi need an m1 atx
    By McGinty in forum Power Supplies
    Replies: 5
    Last Post: 04-27-2007, 10:10 PM
  2. Probably a simple question...... Sorry!
    By dsj1979 in forum Centrafuse
    Replies: 1
    Last Post: 12-01-2006, 10:07 AM
  3. m1 atx is killing my battery on taxi mode
    By cass944 in forum Power Supplies
    Replies: 4
    Last Post: 11-23-2005, 09:54 AM
  4. M1 ATX, hangs. Help a swede in need.
    By Biograph1001 in forum Power Supplies
    Replies: 12
    Last Post: 11-18-2005, 09:01 PM
  5. OPUS simple question
    By Frankino in forum Power Supplies
    Replies: 9
    Last Post: 06-08-2005, 03:56 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
  •