Im running a 6 axis Hanhwa screw machine and the upc battery died completely. The zero return alarms are apearing. In the manuals it doesnt show how to zero return and theres no zero return when you start the machine because the battery stores it. The controller is a Fanuc 18i. Also is there any tips for recharging the batteries because it says to use lithiium D batteries that are not rechargeable so they have to be replaced once a year.