Hell mhlb This issue can be caused by old firmware, loose connection, faulty battery, or a faulty UPS. I would suggest that you clear the error, update the firmware if a newer version is available, and swap the battery with the one from your other UPS. If the error returns then parts will need to be replaced. If it returns on the other UPS that you moved the battery to then it would appear to be the battery. If it returns on the original UPS the error was on with a different battery then I would suspect a faulty UPS. Thanks
I have alarm #149 showing on my Dell Rack 1000W UPS. The user manual says this alarm is "A faulted battery string has been detected and as a result, the charger is disabled." Reseating the battery did not resolve the error. I switched the battery with another similar UPS, and no error appeared, so the problem might be in the UPS and not related to the battery. What could have gone wrong if not the battery? Any further tests I can do? Can I simply re-enable the charging?  Appreciate your help...
UPS Alarm #149