Question about UPS

Razero · December 12, 2019

First off, i wanna say that this is my first time dealing with a ups so please bear with me

So I got my apc back ups(https://www.apc.com/shop/in/en/products/APC-Back-UPS-1100VA-230V-without-auto-shutdown-software-India/P-BX1100C-IN) today and before using it on some costly equipment i wanted to test it, So far no sparks like the last one i returned, but the occasional brrrt sound while changing between battery and mains which (i think) is normal, but one thing i noticed is when the ups isnt connected to anything and i have the main supply on with ups power off and switch it off after sometimes without
touching the ups power button the fan starts running for a short while, So is this normal? i thought it was supposed to switch on fans during the charging process to cool down the battery or something? not after disconnecting it?

Also, is inverting a ups upside down harmful?