Apc UPS

[videohalp]

My small (cereal box size) APC UPS' battery died after 3-4 years. I was wondering if the bigger (small tower size) APC UPS have a better service life.

[aedipuss]

they use lead/acid batteries also, and all need replacement batteries every 3-5 years.

[rallynavvie]

they use lead/acid batteries also, and all need replacement batteries every 3-5 years.

Agreed. I've owned many different brands and sizes of UPS over the years and generally I replace them every 3 years. The longest I've seen one last is my current APC that's coming up on 4 years, but it has rarely ever come on since a new utility company started servicing the local lines so it is still holding a decent charge. It'll probably still need to go by this fall.

[Nelson37]

Other than unusual power conditions, the biggest cause of early failure is overloading the unit. A 450 watt unit should only be supplying about 400 watts, you want to keep power draw about 10% below the rated number. Bigger is better. Three to five years is about average lifetime.

Interesting tidbit, I always thought Watts + Volts * Amps, but apparently with Battery Back-ups, that is not true. There is some kind of "conversion factor", kind of like the rounding issue with hard drive storage numbers. They advertise whatever number is higher, but the actual figure is somewhat lower. Roughly 10%, apparently all the manufacturers use the same numbers so comparisons are equal.

These units are NOT "UPS" units, they are battery back-ups. There is a big difference.

[rallynavvie]

These units are NOT "UPS" units, they are battery back-ups. There is a big difference.

How are you differentiating them?

[Bjs]

One would be "mains" power fail ... the other via inverter (remote locations)

Battery's last longer if maintained properly and drain never falls below 70% of total battery charge ... this is for each individual battery, not as a whole.

Its rare to see either use 9 plate cells which is why my batteries can last for 8+ years.

[SLK001]

Interesting tidbit, I always thought Watts + Volts * Amps, but apparently with Battery Back-ups, that is not true. There is some kind of "conversion factor", kind of like the rounding issue with hard drive storage numbers. They advertise whatever number is higher, but the actual figure is somewhat lower. Roughly 10%, apparently all the manufacturers use the same numbers so comparisons are equal.

Watts does equal Volts x Amps. However, this formula applies to DC and AC when the volts and the amps are in phase. For a switching power supply (RE: computer usage), the demand of the SPS is NOT in phase, so you can't use 10-40% of the UPS's capacity.

[Nelson37]

A true UPS is ALWAYS on battery, there is never any "switching" that takes place. A battery back-up switches to battery power when there is a power failure.