Eaton says that alarm error #191 comes from a battery test, where batteries are put under load for 25 seconds. (If the alarm is unexpected, you might have enabled the automatic battery test.)
# 191 is test failure for battery internal resistance. So, need to locate and replace the bad battery, then run the battery test again manually. If batteries are good, make sure no connector is corroded or loose.
Answers & Comments
Eaton says that alarm error #191 comes from a battery test, where batteries are put under load for 25 seconds. (If the alarm is unexpected, you might have enabled the automatic battery test.)
# 191 is test failure for battery internal resistance. So, need to locate and replace the bad battery, then run the battery test again manually. If batteries are good, make sure no connector is corroded or loose.
Shut down the UPS and replace the batteries.