How do I start a SURT10000XLI with low batteries(<50V) ??

[BillP]

This question was originally posted by Ole on APC forums on 3/11/2013

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I have a number of SURT10000XLI, where the batteries are lower than 50V, some are even below 40V. The UPS does not seem to start, unless you have 4 batteries, with at least 80V each. Are there any tricks to get the UPS charger working if your batteries are lower than 40 - 50V ???

Kind regards

Olebenny

[BillP · Accepted solution]

This reply was originally posted by Angela on APC forums on 3/11/2013

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i don't think so and then you wouldn't want to necessarily try and charge those batteries that have been sitting at low voltage and cause more problems (i.e. overcharge, thermal runaway in extreme circumstances). my best recommendation is to get some fresh batteries for this UPS and if they are stored for a long time, adhere to battery storage recommendations outlined in the knowledge base @ http://www.apc.com/site/support/index.cfm/faq/ , article ID FA156516 (Battery Discharge During Storage) & FA157446 (Battery Damage When Battery Is Left Discharged)

[BillP]

This reply was originally posted by Ole on APC forums on 3/12/2013

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Hello Angela

Thanks for replying.

So the answer is no ??

Which means you need a set of new batteries, if your UPS runs on  battery until the batteries are flat.

After this, you can't start the UPS without a set of new batteries ???

Kind regards

Ole

[BillP]

This reply was originally posted by Angela on APC forums on 3/12/2013

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No - when the UPS runs on battery, it does not discharge them below a certain voltage where then it knows it can charge them back up.

If your batteries are below that level (improperly stored or not periodically charged), they cannot charge back up and are beyond the point of return. As batteries get older over time, I think they become more sensitive to that voltage point and after the more number of deep discharges, the higher the risk over the years to not be able to charge back up, thermal runaway, etc. Batteries consists of chemicals as you may know so after time, the chemical reactions don't work so well anymore.