SoSo CAD
Technical guideFree to read2020

5 Areas of UPS Failure to Look Out For (Michael Fluegeman, Antonio Tan III)

FacilitiesNet / Building Operating Management · Michael Fluegeman, Antonio Tan III

Part 3 of a four-part series on preventing critical facility downtime; it explains that UPS failures coinciding with utility outages are the costly ones and lists five warning areas.

Go to the original source
On this page

Overview

This 2020 article in FacilitiesNet / Building Operating Management is part 3 of a four-part series on preventing critical facility downtime. Its authors are Michael Fluegeman and Antonio Tan III. The core message is that the costly UPS failures are those that coincide with utility outages.

A UPS bridges the gap between utility failure and generator pickup, sometimes needing 10 minutes or more of autonomy. The article lists five warning areas: bypass operation, weak battery alarms, lead-acid end-of-life, dirty filters and room temperature. A UPS on bypass provides no protection against utility failure, and bypass alarms are frequently ignored until the load drops.

A battery rated 8 minutes when new may degrade to 5-6 minutes, or fail to zero with little warning. Lead-acid battery end-of-life and premature failure are a major cause of UPS failures, and batteries should be effectively tested every year. Dirty air filters can overheat internal components without triggering over-temperature alarms, and high room temperature can force transfer to bypass. The text is qualitative and experience-based; related standards are IEEE 450 and IEEE 1188.

Key points

  1. A UPS bridges the gap between utility failure and generator pickup, sometimes needing 10 minutes or more of autonomy.
  2. A UPS on bypass provides no protection against utility failure; bypass alarms are frequently ignored until the load drops.
  3. A battery rated 8 minutes when new may degrade to 5-6 minutes, or fail to zero with little warning.
  4. Lead-acid battery end-of-life and premature failure are a major cause of UPS failures; batteries should be effectively tested every year.
  5. Dirty air filters can overheat internal components without triggering over-temperature alarms.
  6. High room temperature can force transfer to bypass.
  7. The five warning areas: bypass operation, weak battery alarms, lead-acid end-of-life, dirty filters, room temperature.

Using it in design

  • Size UPS autonomy with an end-of-life derating (for example 8 min new, 5-6 min aged) and show both values.
  • Add operational alarms and checks to the O&M export: bypass status, battery health, annual battery test, filter maintenance and UPS room temperature limits.
  • Define bypass status as a high-priority alarm in the monitoring system.

Monthly newsletter · free

Keep your reading list current

Once a month: new library sources, changes to Turkish regulations and upcoming data centre events.

SoSo CAD

Review your power design in SoSo CAD

Inspect supply paths, equipment loads and UPS failure scenarios in one model.

Request a demo
Single-line diagram in the SoSo CAD power and capacity workspace

Who should read it

Facility teams responsible for UPS maintenance and operation, and electrical designers sizing autonomy.

Related standards

  • IEEE 450
  • IEEE 1188

Publication details

Authors
Michael Fluegeman; Antonio Tan III
Publisher
FacilitiesNet / Building Operating Management
Year
2020
Document language
English
Source type
Expert / community
Access
Free to read
Licence
Copyright retained; citation only — the publisher’s terms apply to the original document

Citation

Michael Fluegeman; Antonio Tan III (2020). 5 Areas of UPS Failure to Look Out For (Michael Fluegeman, Antonio Tan III). FacilitiesNet / Building Operating Management. https://www.facilitiesnet.com/datacenters/article/5-Areas-of-UPS-Failure-to-Look-Out-For--18999

UPSOperationsReliability

Events on this subject

Browse the events calendar

All content and rights belong to the respective authors and publishers. SoSo CAD provides only the citation, its own summary and a link to the source, and is not responsible for the sources' content.