KEYPOWER DCDC restarting pc when cranking

Mp3Goose_Your King · 06-07-2003, 12:29 AM

Anyone using a keypower dc-dc that doesnt' doesn't restart the pc when you crank without doing anything special.

cproaudio · 06-09-2003, 12:07 AM

Not sure if this is the one you have http://www.keypower.com/proddetail.a...&linenumber=15 From the looks of it, the spec is not that great for car use. The min voltage is 9V. some older battery will dip down to 8 volts during crank. You may have to get a tank circuit. It's only 60% efficient. 40% of the power intake turns into heat. Teamperture range is not that great for car use either. Those are pretty important to me when I look at DC to DC PSU. Where I live, the car interior can get to 130F-140F in just 15 minutes after parking in the sun during summer time. I have a bad battery that barely starts my truck but my PSU doesnt reboot the PC when I start. my PSU is over 90% efficient so I can run my PC at least 2 hours before it kills my dying battery. All those are really important to me ya know.

SuperMatty · 06-09-2003, 01:14 AM

Mine restarts as well. But really, what other kind of DC-DCpower supply could you use in a car that will power an AMD Athlon XP 1700+ and 7200 RPM drive?

ODYSSEY · 06-09-2003, 01:43 AM

I have one and so does BrentP4. Mine did restart during the time I had it installed in my car. I'm currently upgrading my system, so it is not in the car. I'm pretty sure mine was do to sub-par grounding.

Brent's system sometimes reboots. During our 4 day trip to Florida, it only rebooted once. We also were able to leave the computer running while dining, fueling and visiting some friends (30mins - 2 hours). The computer never rebooted. The one time it did reboot was the morning we left, really early and humid. Humidity can kill batteries.

Get out your multimeter, check the volts before crank and after. Check directly at the battery and then at the PSU connection. Both should be about the same. If not check your wiring, must importantly your ground. You need a good path for the volts to flow.

Edit: You might want to have a load test done to your battery. It would rule out the battery being bad.

Telek · 06-09-2003, 02:24 AM

The type of computer that you are powering has very little to do with wether or not it will reboot during cranking.

Computer = 5A
Starter Motor = 60-200A

Which one do you think will have a larger effect?

A simple capacitor and diode can stop the computer from rebooting. It's < $10 and very easy to assemble.