Battery, 1uF, and M3-ATX wiring problem

AIR-V · 08-04-2008, 04:06 PM

Hi All,
I need a technical help to clarify my installation.
I've got a Santa Fé 4WD 2.0CRDI with a 100Ah battery

Actually my Pc with M3-ATX is connected to the smoke Light plug and working (fine) only if i turn on the key or running my car.

Starting Sequence :
I need to wait the sparke plug warming up the fuel and after i can running the engine, but the PC is starting due to power on car.

In this case the autostart from M3-ATX is not efficient, why ?
Because the CRDI is a power hungry machine, and the motor ignition provoke a voltage shutdown (lights, clim and other are shutingdown during), results : the PC is down too.

To solve this problem: i'm starting the car and after , starting myself the PC by using a power switch connected on POWERSW connector of my motherboard.

I would like to connect my PC directly on the battery and use the S3 standby mode on PC (the goal is running it in less than 10sec

).
My questions are :

When the ignition power, is my pc still power enough or the ignition will "pump" all power ?
Is the standby mode will discharged my battery if i don't turn on the motor during few days?
I've seen a KBD power on on motherboard , i presume i need to turn off this b
ecause it will "pump" for nothing ?

I've already got some part but i didn't know how to wiring all ?
1uF condenser, working fine but i don't know how to wire it in car.
Old battery (Spare solution because i don't know if it's working)
can we connect 2 batteries in 1 car without problem? and how?

AIR-V · 08-05-2008, 03:22 AM

up

DarquePervert · 08-05-2008, 07:11 AM

1. I don't know about the M3ATX, but the better power supplies will survive engine cranking. (I believe that's what you're asking)

2. Yes, standby mode will drain your battery. How quickly depends on the power draw of the PC when in standby and your battery.

3. This is an option to have a keypress boot up the PC. I would disable that option.

SPElectronics · 08-05-2008, 10:08 PM

Most vehicles have a power wire that stays ON even during cranking, but of course if the voltage drops too much it will still cause your supply to drop out, so it may or may not work for you. Your best bet is to wire the main power wire directly to the battery, so there is less chance of the voltage dropping out to the power supply, and find the one ignition wire that is on even during crank and wire your power supply ignition wire to that one. If you STILL have a problem with voltage, you can either upgrade your battery, or add a small 12v backup battery.

AIR-V · 08-06-2008, 11:41 AM

Quote: Originally Posted by SPElectronics

Most vehicles have a power wire that stays ON even during cranking, but of course if the voltage drops too much it will still cause your supply to drop out, so it may or may not work for you. Your best bet is to wire the main power wire directly to the battery, so there is less chance of the voltage dropping out to the power supply, and find the one ignition wire that is on even during crank and wire your power supply ignition wire to that one. If you STILL have a problem with voltage, you can either upgrade your battery, or add a small 12v backup battery.

Is it a good way to test the voltage drops with a light connected on the battery when crancking ????
I would not burn my power supply too fast

How to connect a backup battery ?

Thanks for all

billmee · 08-07-2008, 07:33 PM

AIR-V My motor is also a diesel and very power hungry during startup.

I'm using the signal to my tail light to turn the PC on, this way I can wait until after the engine has cranked to start it.

I connect the tail light wire to my Carnetix ACC connection and also to one pin of the serial port for automatic UPS shut down.

I do not regulate it, protect it, or have any troubles.