294 Determine the operational mode using the [RAID]switch.S: Single mode (Default)R5: RAID 5 modeR6: RAID 6 mode5 Turn on the power of the recorder by pressing the[POWER] switch while holding down the [USE] but-ton until the buzzer starts sounding.The recorder will start up in the selected operational mode.Important:• Do not change the operational mode after starting the sys-tem operation. If the operational mode is changed afterstarting the system operation, accessing the recorded datamay fail.* When using a recorder (not a network disk recorder), refer tothe manuals provided with the recorder for how to operate.[USE] button [RAID] switch10 Close the front cover and lock it by pushing andturning the key to the left.Keep the key in a safe place.11 Check the disk information.The following can be checked on the "Disk information"page on the setup menu of the recorder. Refer to the man-uals provided with the recorder for further information.• Total capacity of the hard disk drive• Available (remaining) capacity of the hard disk drive• Hour meter• Operational mode of the hard disk drive• Time and date range of the images recorded on thehard disk drive.Note:• It is impossible to remove all the HDD units in the exten-sion unit using the buttons and the LCD on the front panelwhen running in the RAID 5 or RAID 6 mode. Refer topage 31 for information on how to replace a faulty harddisk drive.* When using a recorder (not a network disk recorder), refer tothe manuals provided with the recorder for how to operate.● Determine the operational modeThe default operational mode is "Single". To run the system inthe single mode, the following procedures are not necessary.1 Turn off the power of the extension unit and therecorder.Turn off the power of the power of the extension unit byfollowing the instructions in the "Turn off the power of theextension unit (page 18)" section.2 Turn on the power of the extension unit.The following operations are to be performed on the net-work disk recorder.*3 After inserting the key provided with the networkdisk recorder into the key hole on the front cover ofthe network disk recorder, push and turn it to theright to open the front cover.(2)(1)(1)(2)