Load on battery during AVR boost

[eeolson_apc]

When a UPS is indicating AVR boost for undervoltage, is it drawing from the battery to make up for it? We have a UPS which stays in AVR boost state for extended periods, and would like to know if the battery is being hit during these times.

Also, if anyone can point to an APC white paper or something on how the AVR works, let me know...

thanks!

[BillP · Accepted solution]

hi-

the boost and trim functions do not use the battery. they use an internal transformer. if your UPS is in constant boost, even though it doesnt draw from the battery, you probably want to see if you can figure out what the issue is. constant use of the transformer heats up the UPS and in the long term, could shorten the life of the battery or the UPS. boost or trim isnt meant to be on 24/7. check your incoming voltage to see whats going on.

in regards to more info on AVR, check this thread: https://community.exchange.se.com/t5/Datacenter-Forum/bd-p/datacenter-forum

there are some helpful posts.

[this link|http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=715] is from our knowledge base and can tell you when the AVR boost or trim will kick in (at which voltages).

i cant find any white papers or anything but essentually, the UPS boosts or trims the voltage accordingly for undervoltages or overvoltages by percentage. i believe the percentage is 12% and some have a double boost of 24%. it takes this percentage from the input voltage.

hope this helps. if i find anything else, i'll post it as well.