HHR Ed Posted June 22, 2012 Report Share Posted June 22, 2012 Alternators are designed around the battery setup, not the wattage, You cannot supply total system wattage from an alternator. So the question is, can a 270A alt charge 4 D3100s and a D6500. Answer, yes How long will that charge take is the question that should be asked. So lets try and figure that out. 4 D3100 and a D6500 will have a combined aH rating of 515ah So we see a factor of 1.9. That means that with ever 1 minute of discharge, it will take 1.9 minutes of charge to top the batteries off. Now how long will it take to totally deplete those batteries with 15,000w? If calculating dropping to 10v thats about 1500a of current. According to the amperage capabilities of the D3100s over time, that will be about 10 minutes of a constant tone at 100% amplifier power. Now playing music with breaks can extend that over twice as much. And of course a higher amp alternator can extend that even further. But lets say that he plays a solid full power tone for 10 minutes, it will then take 19 minutes to charge back up. Or we can figure that with the car running and charging during that full power tone, it will take a about 15 minutes to drop the batteries to 10v. For every 1 second of a bass beat, the alt will need 1.9 seconds to keep the batts fully charged. If there is only 1 second pause per 1 second bass beat, he can still play a constant full 15,000w bass beat for over half an hour. Quote Ed Lester ShowtimeSPL Host Showtime Electronics Video MarketingMy old Build Loghttp://www.stevemead...08/#entry511451http://www.youtube.com/showtimespl 5 time dB Drag Finalist Last ride 2007 HHR, current dB 153.5 and bass race 149.4 dB. 153.0 dB on music New Ride, 2008 HHR SS. Build under way. Loudest score ever = 171dB 2009 dB Drag Racing, North American Points Champion Link to comment Share on other sites More sharing options...
HHR Ed Posted June 22, 2012 Report Share Posted June 22, 2012 BTW, if you want to run 9000w for headroom, that is great, it'll run much longer and more efficient. That battery setup will supply a 9000w solid tone for over 15 minutes. With the alternator running it'll be over 20 minutes. I dont think anyone will play a 20 minute tone at full power on 9000w for 20 minutes. On common music and playing habits of the common person, you will have no problem playing for a few hours. Quote Ed Lester ShowtimeSPL Host Showtime Electronics Video MarketingMy old Build Loghttp://www.stevemead...08/#entry511451http://www.youtube.com/showtimespl 5 time dB Drag Finalist Last ride 2007 HHR, current dB 153.5 and bass race 149.4 dB. 153.0 dB on music New Ride, 2008 HHR SS. Build under way. Loudest score ever = 171dB 2009 dB Drag Racing, North American Points Champion Link to comment Share on other sites More sharing options...
HHR Ed Posted June 22, 2012 Report Share Posted June 22, 2012 Quote Ed Lester ShowtimeSPL Host Showtime Electronics Video MarketingMy old Build Loghttp://www.stevemead...08/#entry511451http://www.youtube.com/showtimespl 5 time dB Drag Finalist Last ride 2007 HHR, current dB 153.5 and bass race 149.4 dB. 153.0 dB on music New Ride, 2008 HHR SS. Build under way. Loudest score ever = 171dB 2009 dB Drag Racing, North American Points Champion Link to comment Share on other sites More sharing options...
HHR Ed Posted June 22, 2012 Report Share Posted June 22, 2012 I think its just a great misunderstanding that people have about alternators. You cannot simply multiply the alternator amperage by your voltage and figure how powerful of a system it can run. What that will tell you is how much power the alt can supply to your system. As I stated before, "Time is the forgotten factor when discussing power" The sole purpose of a battery is to store power over time. We use batteries because there is no way an alternator can supply your total system wattage. If you are under the assumption that this is how it is figured, I invite you to start your car and then unplug the batteries, then drive around with headlights and just the head unit turned on. So we must figure system wattage based on the batteries we put in our system. Then we can figure the alternator needed to properly charge those batteries, Ideally we do want the lowest charge factor we can get. I mentioned earlier that the above system will have a factor of 1-1.9. A factor of 1-1 is ideal but it is very difficult. You can have 2 alternators supply a total of 515A to the above setup for that 1-1. But this does not limit wattage to 5-6k. This just ensures that those batteries are kept charged at 1 minute of charge for every minute of play. But the batteries alone can supply up to 15,000w. My example is my old setup with 10 batteries off of my stock alternator. I would bass race 10,000w and drop to 12.9v DC after 30 seconds. I would demo for 5 minutes on 10,000w and drop to 12.2v. I would then turn off or turn down my system and charge up for 10 minutes and do it all again. When I drove around, Id play maybe 80% volume and would play my full 1 hour drive and never drop below 12.2v Quote Ed Lester ShowtimeSPL Host Showtime Electronics Video MarketingMy old Build Loghttp://www.stevemead...08/#entry511451http://www.youtube.com/showtimespl 5 time dB Drag Finalist Last ride 2007 HHR, current dB 153.5 and bass race 149.4 dB. 153.0 dB on music New Ride, 2008 HHR SS. Build under way. Loudest score ever = 171dB 2009 dB Drag Racing, North American Points Champion Link to comment Share on other sites More sharing options...
Emmet Posted June 22, 2012 Report Share Posted June 22, 2012 Well... this has been informative. Cheers Ed. Quote i shook this one kids hand and it just folded in mine. long story short i fucked his girlfriendso.. yeah.. You want this to happen to you? Give decent handshakes people. I was gifted with an innate ability to distribute wholesale ass beatings in a timely and orderly fashion. Link to comment Share on other sites More sharing options...
98GCLimited Posted June 22, 2012 Report Share Posted June 22, 2012 Wow, that's quite abit more then I was expecting... I was thinking 5k tops.... lol.... Guess I better expand my horizons! (and bank account) lol Id say the mechman 270 and 2 d3100 would be good for 5k if not more. Quote Link to comment Share on other sites More sharing options...
volvowith18psi Posted June 22, 2012 Author Report Share Posted June 22, 2012 Great info! Thank you!! Quote Link to comment Share on other sites More sharing options...
zack_e89 Posted June 22, 2012 Report Share Posted June 22, 2012 Great info! Thank you!! Definitely...thanks ed Quote 97 Suburban 8 custom PSI Platform 3 18's Link to comment Share on other sites More sharing options...
ch0sen Posted June 22, 2012 Report Share Posted June 22, 2012 I read all of that and i was like, wow, i have watched this somewhere Quote My current 95 Jetta Build w/ pioneer h/u 2 RD Sonance 10's with flatwind coils 2 Audiopipe apsm 1500.1s 1 Hifonics Brutus Elite 60x4 1 XS d925 1 Stinger spv35 1 1000 amp lead acid 50 ft of 0/1 ofc from Audiotechnix all powerbass components, and coaxils, 4 sets buildlog = http://www.stevemead...2-rd-10s-build/ My build for my wife. http://www.stevemead...01-f-150-build/ Link to comment Share on other sites More sharing options...
XX7R Posted June 22, 2012 Report Share Posted June 22, 2012 Holy crap that was a lot of info. If you had 4 d3100s fully charged and played 15,000 watts rms clamped, your voltage wouldn't stay up for very long with a mechman 270. Your feeding the batteries approximately 225-250 amps depending on what rpm your at. And your pulling around 1500 amps of power depending on the amp(s) . That wouldn't work out so well for daily for the op if he could only listen to his system for a little bit and then have to turn it down to let the batteries recharge. Just saying Quote 1990 Nissan 300zx Twin Turbo - Summer Ride(No system yet, lookin to get it up to 450-500 horse first!)2006 Chevy Malibu - Daily DriverDC Level 5 15", 2 APSM-1500's, 3.88 cu. ft. tuned to 32hz1992 Honda Prelude - SOLD2 18" TC 3hp Woofers on a Crescendo BC3500.1d, 12.7 cu. ft. tuned to 35hz Link to comment Share on other sites More sharing options...
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