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PC UPS maintenance advice needed, for better battery life.

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Junior Member level 3
Sep 30, 2009
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Some basic questions with reference to normal domestic PC UPS units and maintaining their good battery life and performance.

1. Is it better to always leave the UPS connected to power. Which means the wall power socket switch is always on, but the ups button is off until we need to use the system OR...... is it better to switch off the wall socket when not using the PC and the UPS is off. Which of this will ensure better battery life ?

2. Is it good to (maybe once a month) completely discharge the UPS by switching off the wall socket. Letting it beep till final warning stage and then powering the wall socket back on so that it gets charged again for about 5 hrs. Then repeating the same process again. So totally 2 to 3 discharge & charge cycles. Doing this process is this good for the battery ?


Re: PC UPS maintenance advice needed, for better battery lif

1) It should be better if the UPS is always connected to the mains socket, charging the battries. But it depends on your UPS: some of them when turned off are in a "standby" state in which the battery charger is on; some others turns off the battery charger. I prefer the first one devices, those with the battery charger active even when turned off.
2) NO, it is not good. If you take a look to Pb batteries characteristics, you will find that a deep discharge is not good for the battery life!
3) Even worst for battery life (than a deep discharge) is the batteries temperature: their operating life can be almost halved if you keep them to 40°C instead of 25°C!

They always run in an aircon room. So the temperature part is not an issue i assume.

So its better to leave the power wall socket on (thereby supplying power to the UPS 24/7) but the ups output/operation switch can be off. I think my ups should be in charging state even of the output power switch is off because when the battery is getting charged (maybe after a power failure) even if i switch off the operation switch it still shows the under charge in progress light and so is presumably drawing power from the wall socket and charging. After about 10 mins it switches off the under charge light.

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