Mac min sleep solution

**MikeH** · 04-12-2005, 04:40 PM

Guys,

I think we've got a reasonable way to let the mac sleep when the ignition is turned off. Take a look at THIS. Let me know your thoughts. 100mA seems like a reasonable amount of current....if your battery is in relatively good shape.

Are any of you guys car audio/alarm system installers? How much current do these systems draw when the ingition is off? Anything we can compare to?

**anthropod** · 04-12-2005, 04:49 PM

100ma sounds good. I would be very comfortable with that. Reading on other forums it looks like a radio draws about 30ma with it off.

I might not want it to be asleep for a month, but I would have it off if i was vacationing a month in the Fiji islands, and not driving.

**Bugbyte** · 04-14-2005, 01:49 AM

Mike, this is an OUTSTANDING solution! No tank battery, no significant power drain, and nearly instant on upon starting the car.

The Mini is looking better and better for a Car PC. Can't wait for the P1900.

**sdashiki** · 04-14-2005, 11:37 AM

id still go with a second battery with an isolator. if you run a nice sound system with a high draw amp, like me, you might as well. you can sit with the car off (not in florida in the summah tho lemme tell ya) and not worry, and plus it gives your sound system its own battery so the car can keep its own and not be drained during "loud" music.

im waiting on the PSU myself, but im waiting on alot more $ first

**MikeH** · 04-14-2005, 11:45 AM

sdashiki,

I tend you agree with you. The standard car battery is designed to supply a very large "gulp" of current when you crank your engine, and then become fully recharge while you are driving. It does not tolerate long periods of deep discharge (ie, sitting with your CarPC playing musing thru your "high draw" amp). However, if you have a secondary battery that IS designed for "deep discharge", AND you keep it charged thru a battery isolator of some sort, this is the best solution for those who want to "sit and listen". It also really helps the Mac mini sleep current drain issue.

Perhaps you could give us some suggestions on good deep discharge batteries and reasonably priced battery isolators...?

**sdashiki** · 04-14-2005, 11:53 AM

Umm id have to say :SEARCH: the forums for that

but Optima Yellow Top is always on my list of batteries

**MikeH** · 04-20-2005, 10:50 AM

Good news/Bad news:

The Bad News:
I'm sorry to inform everyone that there seems to be a problem with this proposed sleep solution. It seems that after several hours of sleeping with +12V as the input power, the Mac will not successfully resume from sleep. Thanks for Matt Turner (http://www.tunertricks.com/blog/) for his expert installation skills and technical help in discovering this problem. We are still testing this configuration since it would make life very simple for the Mac mini sleep mode. But it appears that the Mac will sleep for "a while" and resume properly, but if left for >3 hours (testing so far) it will not resume properly. The Mac APPEARS to be resuming (HDD spins up, USB powered), but there is no video output. We'll let you know if we find a solution to this.

Good News:
The P1900 can be jumpered to provide +18.5V output for sleep mode. So far this sleep configuration works 100% of the time. The only downfall is that it takes about twice the current that the "sleep diode" method takes (200mA vs 100mA during sleep). We are testing the longevity of the car battery's ability to provide this current, but initial indications are that, if your battery is in reasonable shape, this current drain will be acceptable for "days" of sleep. We will continue to report on this as the tests continue.

**sdashiki** · 04-20-2005, 11:09 AM

IF ya wanna sleep.
Ya gotta gets another batterreeep.

**Qbancash** · 04-20-2005, 11:27 AM

Thats actually a MAC PROBLEM.. IT happens to my Desktop, my cousins G5 and other machines I've had on the past....

The Bad News:...........

Find out qith apple because I think there's a fix and it might still work

**sdashiki** · 04-20-2005, 01:43 PM

my G5 had that problem of no video on wake before.

solved it by moving the graphics card away from the PCI card slots because it was sandwiched by a PCIx card I have and was overheating. And on startup and from wake all G5s are "pushed" to their limit in terms of work. Check yer Activity monitor and watch it spike when you startup and you hear all the fans turn on and whirr very fast for about 10-60s depending.

The whole voltage drop may be correct, but i think its a moot point im working thru on this and another thread. A second battery in a serious carputer/caraudio situation is a definite MUST to me. Saves hassles, time and money in the long run.