Connecting a larger external battery to a UPS: forum comments:

Small UPS are usually made to run only half an hour to 1 hour depending on the load and the internal components heat up after that time and also charger is made to charge small battery.

Better go for a sinewave inverter which can run computers with large battery.

i am using it presently my ups bty died got myself a external bty my laptop runs for 5 hrs on it.

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last updated 14 Apr 2008