Purpose of runtime calibration

[lunadesign_apc]

This was originally posted on APC forums on 7/6/2014

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I have two questions about runtime calibration:

1) Is the only benefit of runtime calibration that the "runtime remaining" figure displayed in PowerChute will be more accurate?

2) Is the result of the runtime calibration stored in the UPS itself or in the PowerChute software?  (I ask because I only have PowerChute installed on a single laptop that I sporadically connect to different UPSes for diagnostic reasons.)

Thanks!

[BillP]

This reply was originally posted by Angela on APC forums on 7/6/2014

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Hi,

Yes, a runtime calibration for UPSs at a minimum helps re-calculate the available on battery runtime a UPS has.When a UPS is online, this runtime value is a really good estimate and can sometimes be inaccurate, especially if the UPS does not operate on battery often (in such cases where the environment does not have many power disruptions) or your load has changed drastically. It is also helpful to do after you replace the battery and if the value does not update at that point after doing a self test. Runtime calibration can also help detect a bad battery but that is also what the UPS self tests helps do in a quicker time frame typically than a runtime calibration though. We usually recommend the runtime calibration after the battery has been replaced and depending on the situation, no more than once to twice a year tops since it will discharge your UPS battery and the more times you do that, the quicker the useful life of the battery declines.

Runtime values and any calibration information is all on the UPS itself.

[lunadesign_apc]

This was originally posted on APC forums on 7/7/2014

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Angela - Thanks for your helpful answers.  So just to confirm, if a UPS isn't connected to a computer and being continuously monitored with PowerChute, there's really no benefit and it's probably better to not have the batteries go through a discharge cycle at all, right?

[BillP]

This reply was originally posted by Angela on APC forums on 7/7/2014

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Yes, I'd agree. If you never need to look at or use the available runtime value for any function (like planning a graceful shutdown), then I wouldn't do it. You can likely just monitor the available runtime you receive (knowing what the "norm" is and when it starts to decline" and go by the audible indicates for any other issues. Depending on your UPS model, you'd see the runtime value on the UPS LCD (if applicable).

Let me know if you have any other questions.

[lunadesign_apc · Accepted solution]

This was originally posted on APC forums on 7/12/2014

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Thank you very much for your helpful answers!  I really appreciate it.