CajunWon
join:2005-12-30
Cary, NC
 ·ViaTalk
| reply to shortckt
Re: Home UPS powered by car battery: failed
apcupsd software is interesting, but appearantly not applicable to my setup.
Following a little more research, and to aid others considering this DIY approach to extended UPS protection:
The APC350 cannot know the battery reserve capacity unless using the PowerChutePro software for recalibration. That process would require the APC to fully charge a drained battery -not good for the battery and likely not good for the APC charger. Also the Powerchute software, if running, would perform a shutdown within 3-5 minutes -therefore the software cannot be used with an oversized battery.
Since the APC doesn't know the battery capacity it will begin the 1 second sound warning within 3-5 minutes of power outage, but will continue to output proper current until depletion. If turned Off, the APC will not restart without Utility power present (therefore mine didn't actually fail).
The oversized battery must be externally charged every 6 months and recommended to 'shake' the battery every 6 months.
Use this calculator to estimate reserve time on your chosen battery. Simply input the battery amp our rating and your total equipment hourly usage in amps. »www.smartgauge.co.uk/calcs/peukert3.xls
Amps = Watts/Volts
e.g. 15" monitor 40 Watts; basic desktop PC 85Watts
125 total Watts divided by 120 US Utility Volts = 1 amp/hour
I believe I read the APC350 peaks at 2.5amps but will overheat if sustaining that current.
(again, I'm no EE -just regurgitating what little I've read. YMMV) |
