Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: Having problems with my inverter... any ideas?

  1. #1
    Newbie
    Join Date
    Jun 2000
    Posts
    43

    Unhappy Having problems with my inverter... any ideas?

    Ok well I've had my computer in for a while, I put it in early summer. It's a celeron 300 with a 6b hd and 48 mb ram. Now here's the thing. I'm using a 300 watt inverter to power it. It's wired directly to the battery in a relay with the ignition wires. It worked fine this summer but now it rarely works. First it wouldn't start with the car once it got colder so I'd have to wait for the car to warm up and restart the car. It would start fine. Now it rarely starts and when it does it shuts down after a little while, the inverter shuts down and gives the red light like it's not getting enough power. Could it be the battery? I don't have any amps right now, but the battery is 5 years old (car is a 96) so does this sound like the battery is going?

  2. #2
    FLAC
    Join Date
    Aug 1999
    Location
    Upper Marlboro, MD 20772
    Posts
    1,311

    Cool

    I'm 100% it is that inverter and the fact it is cold out side. This is why I and people in here keeps telling you guys to go the DC-DC way. One other thing u could try is to add additional battery to your setup, it might help.



    ------------------
    abcd-1
    Author of CobraI and CobraII.
    For more information on the COBRA Application's please visit the link. For the latest or updated info on CobraII please click on the link. Get new updated files for CobraII here. ftp://pictures[email protected]/d:/newdlls
    You can contact me on AOL instant messenger....nick is Cenwesi
    Webpage comming soon!
    abcd-1
    Author of CobraI,II,III and now CobraIV.
    You can contact me on AOL instant messenger....nick is cenwesi or cenwesi3

  3. #3
    Low Bitrate
    Join Date
    Nov 2000
    Location
    grandeprairie alberta canada
    Posts
    66

    Post

    dc-dc isn't exactly the answer i mean i got the parts i needed to build my converter but then i got reading the parts info and well the maxim ics i have aren't supposed to be used below 0degrees celcius when it's currently about -10 on average and i'll probably see -30 before the winter is over. so if you get the wrong components then there isn't any difference besides if the car is warm and the inverter is warm why would that be any different than the dc-dc converter ?

  4. #4
    FLAC
    Join Date
    Aug 1999
    Location
    Upper Marlboro, MD 20772
    Posts
    1,311

    Post

    gee....if thats the case, why is mine still working????...lol



    ------------------
    abcd-1
    Author of CobraI and CobraII.
    For more information on the COBRA Application's please visit the link. For the latest or updated info on CobraII please click on the link. Get new updated files for CobraII here. ftp://pictures[email protected]/d:/newdlls
    You can contact me on AOL instant messenger....nick is Cenwesi
    Webpage comming soon!
    abcd-1
    Author of CobraI,II,III and now CobraIV.
    You can contact me on AOL instant messenger....nick is cenwesi or cenwesi3

  5. #5
    Retired Admin Aaron Cake's Avatar
    Join Date
    Jan 2000
    Location
    London, Ontario, Canada
    Posts
    2,464

    Cool

    And mine. Actually, mine's an Arise unit....

    Anyway, could it be possible that you have a bad connection somewhere being aggrivated by the cold? Or perhaps your relay is not large enough to handle the load of the inverter, so it't contacts have become burned. How big of a relay are you using?

    ------------------
    Aaron Cake
    London, Ontario, Canada

    Player: Cyrix 200, 32MB RAM, 10.2Gig Quantum HD, Onboard EtherNet/Sound/Video, Custom Lexan Case, Arise DC-DC, Win95 Kernal w/Custom Player
    Car: '86 Mazda RX-7 w/Basic Performance Upgrades
    Player: Pentium 166MMX, Amptron 598LMR MB w/onboard Sound, Video, LAN, 10.2 Gig Fujitsu Laptop HD, Arise 865 DC-DC Converter, Lexan Case, Custom Software w/Voice Interface, MS Access Based Playlists
    Car: 1986 Mazda RX-7 Turbo (highly modded), 1978 RX-7 Beater (Dead, parting out), 2001 Honda Insight
    "If one more body-kitted, cut-spring-lowered, farty-exhausted Civic revs on me at an intersection, I swear I'm going to get out of my car and cram their ridiculous double-decker aluminium wing firmly up their rump."

  6. #6
    Newbie
    Join Date
    Jun 2000
    Posts
    43

    Post

    Ok, so I guess it's time to go DC-DC. Are there plans for building your own or what's the cheapest commercial one?

    chris

  7. #7
    FLAC DodgeCummins's Avatar
    Join Date
    Oct 2000
    Location
    DFW area
    Posts
    1,386

    Lightbulb

    Okay to set a few records straight.

    DC-DC is more efficient, so it requires less juice than the inverter route. But in itelf is is just as prone to low voltage problems and the cold, as the inverter.

    Your inverter sucks a lot of amps through the system. 300/12=~25 amps. If you are lucky you probably have a 40-60 amp alternator (if stock).

    Your alternator is recharging the battery, powering the stereo, and the usual car stuff like running the ignition and lights.

    If your battery is about to die, then it never gets fully charged, and especially with the cold probably doesn't get half charged.

    So your alternator is spending most of its free time recharging the battery. and you are getting a low voltage warning from the inverter (check it with a voltmeter)

    Five years is good for a battery, mine only seem to last 4 or so. (OEM battery)

    The other thing you can do is pull the pull the wires from the battery terminals and give them a good cleaning, that is worth a couple of amps.

    The best bet is to buy a new BIG battery, and a bigger alternator. I have a big truck with dual batteries and 150amp alternator. Even so when it is cold, the voltage is low for a while.

    ------------------
    http://www.geocities.com/mr_bubba_zanetti/

  8. #8
    Newbie
    Join Date
    Jun 2000
    Posts
    43

    Post

    I really think it's the battery. I have a pretty big alternator (115 amps!!) it's a 96 Maxima. But like I said it's still the OEM battery so it's 4-5 yrs old. I bet that's it. What battery should I look at? Optima? They're like $150 - anything cheaper?

    Chris

  9. #9
    FLAC DodgeCummins's Avatar
    Join Date
    Oct 2000
    Location
    DFW area
    Posts
    1,386

    Post

    You are lucky to have such a large alternator.

    Like I said, I can't get an OEM battery to last more than 4 years, so yours is about due.

    If your car takes an odd sized battery then you are screwed, but go to Sears etc.

    I believe the top of the line gell batteries (I can't think of the name) are only $150.

    Surely you can do better than that (not at the dealer)

  10. #10
    Newbie
    Join Date
    Sep 2005
    Location
    Fort Myers, FL
    Posts
    1

    Exclamation

    This is an old post, but I ran across it doing some other research on Google, so I'll address the points I find here:

    First of all, just because you have a 115 amp alternator, does not mean that it is constantly putting out 115 amps. That means the peak output of the alternator under a full load is rated at 115 amps. The alternator I have in my '97 Mustang is a 130 amp alternator (stock), but at 1500 RPM, it only puts out ~65 amps. And even less when idling (at 750 RPM). So alternator output varies with engine rotation speed.

    Second, DC-DC conversion is more efficient, but subject to the same pitfalls as DC-AC inversion. The more extreme the temperature (either hot OR cold), the less efficient the conversion process will be. Also, as with any kind of conversion, there is not 100% efficiency. So if you are pulling 300 watts AC out of an inverter, the actual current drain on the inverter's input line would be more than 25 (300/12) amps. There is overhead. Assuming a 90% efficiency (which may be giving your inverter more credit than is due), this would mean that you would actually be pulling 27.5 amps on the input line for a steady output of 300 watts.

    Most automotive relays are rated for 20, 25, or 30 amps. Check the ratings on yours to make sure you're not overtaxing it. Also, make sure your wire gauge is thick enough to allow the passage of current. If you are using thin wires, it is entirely possible that when the wires are hot (regardless of inverter and CPU temp), they will pass the current more efficiently and allow your computer to run. But, in the extreme cold, they cannot pass enough current to allow operation.

    Optima is a good cel battery, but if you're going to spend the money, you should go for a Yellow Top. This is Optima's deep cycle industrial battery. It will take a beating and last you for many years to come. It can be completely 100% drained, and then be brought back to full charge without damaging the battery (unlike a normal car battery). However, you should be careful not to do this while the battery is in your car, because the increased charge requirement will overheat your alternator. Charge your battery to a minimum of 12.6 volts (tested under load) before you charge it using the alternator--at least that's what the alternator's manual suggests.

    cenwesi: There is not enough information available in this post to determine that the problem is 100% with the inverter. It could be with the alternator (output from alternator could be falling as the alternator starts to fail), wires (I've explained why the wires could be to blame), perhaps the computer itself (at such an extreme temperature, could be taking more than the 300 watts to power it), or any other number of components.

    I hope I have addressed all the issues in this post, so that if (like me) somebody runs across some useful information in it despite it being 6 years old now, everybody is better informed. As always, any questions, feel free to e-mail me: eslindsey {at} gmail [dot] com.

    -Eric

Page 1 of 2 12 LastLast

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
  •