On Wed, Nov 16, 2005 at 11:58:34PM +0000, Anthony Anson wrote:
The message <200511161930.35244.bdi-emc@ntlworld.com> from Paul <bdi-emc@ntlworld.com> contains these words:
A quick look at the battery in a 500VA APC UPS - 12v 7AH. At full load, this gives me a 2 minutes, or 14 minutes at half load. A typical car (or motorcycle) battery would extend these times considerably.. Car batteries can deliver in excess of 350A for very short periods.
But you'd have to be sure the charging circuit can without burning out deliver the current the larger accumulator will draw.
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery. -- Chris Green (chris@areti.co.uk) "Never ascribe to malice that which can be explained by incompetence."