Series 16/18/160/180-Model C Maintenance Manual, GFZ-62755EN ...

B–62755EN/018.TROUBLESHOOTING8.14ALARM 306 TO 308(ABSOLUTE PULSECODER BATTERY ISLOW)Absolute pulse coderbattery replacementThis alarm is generated when absolute pulse coder battery becomes low.WARNINGWhen replacing the memory backup batteries, keep thepower to the machine (CNC) switched on, and hold themachine at an emergency stop. Because this work must becarried out while the power is kept switched on and thecabinet is open, only the personnel who have been trainedfor safety are allowed to engage in the work. Whenreplacing the batteries, be careful not to touch thehigh–voltage circuit section (marked and shielded witha shock hazard prevention cover). If you touch thehigh–voltage circuit section when it is uncovered, you willget an electric shock.ProcedureReplace the batteries in the battery case on the front surface of the seriesservo amplifier module or in the battery box connected to the JA4Aconnector of the main CPU board or the JA4B connector of the option 2board.CAUTION1 When replacing the batteries for the series servo amplifiermodule, keep the power to the servo amplifier switched on.2 When replacing the batteries in the battery box, keep thepower to the NC switched on.3 Note that we are not supposed to replace the batteries forthe control unit (for memory backup).339