Hey Guys have a look

MpGa · 09-26-2002, 08:46 PM

Hey guys this is my basic car setup (in theory).lpease tel lme what you guys think.. the relay for the atx switch is called a "one shot" it completes the circuit on for a sec or two.. perfect for the signal to turn on and off the motherboard. Im also looking at a relay that when power is off it switches.

MpGa · 09-26-2002, 08:48 PM

there is supposed to be a box in upper left rpresenting the battery, for some reason it got messed up

Mad Jad · 09-27-2002, 01:14 AM

Good start. May I recommend one thing: a DC-DC ATX power supply. I was getting fed up with the noise (electronic and audible) being generated by the power inverter I had and finally bought a ready-made ATX DC-DC power supply (PC Power & Cooling's). It completely changed my setup. The computer doesn't care whether my engine is on, off, or starting. The computer stays on at all times unless I shut it off -- no interruptions. Ignition switch relay is an option, but I don't always like to have the keys in the car while the computer is on.

Making a drawing is very very useful. Don't do anything to your car without planning it out first. Especially wiring. You can cut down on your installation sessions significantly. I must've taken my seats out about 5 times now to run more cables. And I'm going to have to do it at least once more.

Anyway, good luck to you and let us all know how it turns out.

DON'T FORGET A FUSE if you connect anything directly to battery!

Just curious.. what kind of car are you planning on putting this setup into?

Thanks,
Jad

hijinks21 · 09-27-2002, 08:31 AM

I'd make one change. Go from the battery to the inverter. And put a 30 amp inline fuse in-between.

MpGa · 09-27-2002, 10:05 AM

oh.. yea i did forget the fuse.. ikinda drew this in a little haste.. im getin very antsy

well i was going to put my setup in a Neon put i have to sell it and im moving so it puts things on hold again...Im rally Really hoping in geting a VW jetta, Another option for power (and you guys are gonna laugh) is to get one of those cheap ups at Best BUy (where i work so i get it really cheap) and use the on board shut down option, it would also clean up the signal a little, and you dont have to point out size. .....also i have a 4aug wireing system goint o my R Fosgate amp (700s and He2 10") and speakers, do you guys think i could tap t into that before or after the 1 farod capasitor and get my power to inverter or dc to dc? Thanx again in advance

CrazyLittle · 09-27-2002, 11:35 AM

a UPS is guaranteed to destroy any invertor you plug it into. Not to mention that anything you spend on said invertor and UPS -could- just be put towards a more final solution, like one of ZootJeff's supplies

pigseye · 09-27-2002, 12:56 PM

CrazyL,
Could you please explain why a UPS would destroy an inverter? It's not that I doubt you, I'm just curious.

Thanks,
Pigseye

MpGa · 09-27-2002, 02:23 PM

i was gonna ask the same thing..also about the Itx power supplys, they sell them with a 12v dc input, wouldnt all you need is a regulator to get them to run right off your battery.. or how about a laptop car adapter withe the right volatage and amps? they would be a lot cheaper than a dc-dc..all opinions count thanx

ODYSSEY · 09-27-2002, 02:50 PM

I think it is because an UPS pulls more power when trying to charge the battery. It might send the invertor into over-load.

CrazyLittle · 09-27-2002, 03:27 PM

Quote:

Originally posted by ODYSSEY
I think it is because an UPS pulls more power when trying to charge the battery. It might send the invertor into over-load.

Exactly. Add the power of the charging circuit (let's say, 150w, but I almost guarantee it's more) plus the power rating of your PSU (more like the power consumption of all your parts, but I digress) And if that number's anywhere NEAR the rating of your invertor, you're guaranteed a nice fireworks show.

Re: ITX boards - there's a whole thread on finding a suitable 12v transformer for the ITX DC-DC PSU. The big problem you're faced with is supplying 5Amps at 12v from a plug-in transformer.

MpGa · 09-27-2002, 07:13 PM

what if you have like a 400w inverter?

Gutter · 09-27-2002, 07:15 PM

I saw a tiny UPS for sale the other day that said it would last 18 minutes on battery. Real world numbers: 5-6 minutes.

I'll see if I can find it. Maybe it sucks down less power than those 80lbs bohemoths.

It's the APC Back-UPS ES 350. But these mickey mouse UPS' may still make your inverter go kaput.

MpGa · 09-27-2002, 09:29 PM

yea i was tlking baout using the really low end 100w cyberpower ups
from best buy (i can get it for about $30)

CrazyLittle · 09-27-2002, 09:47 PM

yeah, you'll cook that thing if you've got any PSU over 150w... Heck you might even cook it with an E-Machines PSU

Electronicsuk · 09-28-2002, 03:14 AM

Are you sure the charger inside a UPS really draws that much current? In many UPS systems they will try and use a small lead acid battery. For example a 100w UPS would take around 10A from the internal battery at full current (an inverter usually draws 1A for every 10w). They can get away with using a 5A lead acid (maybe even less) because you can still draw more than the batteries maximum capacity.

So, most lead acid battery manufacturers recommend a maximum charging current of C/5. So in the case of a 5A battery that is a charging current of 1A (12w) maximum the UPS should provide to it's internal battery. There will be a transformer somewhere inside the UPS to get the 12v needed for charging the battery. You are only drawing around 12w from that transformer, and hence 12w from your inverter. When using a transformer the wattage on the primary/secondary will always be the same, although current/voltage will differ. Any other current will be the power you are drawing from the UPS. Say you are drawing 100w, that equals a total of 112w drain from your inverter.

I can't guarantee i'm right here, i'm sure someone will know a little more about this stuff and prove me wrong!

Best regards,
Matthew