• Remove any jewelry or metal objects from your body because they are excellent metal conductorsthat can create short circuits and harm you if they come into contact with printed circuit boards orareas where power is present.• Do not lift a expansion enclosure chassis by the handles of the power supply units (PSUs). They arenot designed to hold the weight of the entire chassis, and the chassis cover may become bent.• Before moving a expansion enclosure chassis, remove the PSUs to minimize weight.• Do not remove drives until you are ready to replace them.NOTE: To ensure proper expansion enclosure cooling, hard drive blanks must be installed in anyhard drive slot that is not occupied.Pre-Replacement ProceduresPerform the procedures described in this section before replacing a component of an SC180 expansionenclosure.Sending Diagnostic Data Using Dell SupportAssistUse Dell SupportAssist to send diagnostic data to Dell Technical Support Services.1. Click Send SupportAssist Data Now. The Send Support Assist Data Now dialog box appears.2. Select Storage Center Configuration and Detailed Logs.3. Click OK.Contacting Dell Technical Support ServicesContact Dell Technical Support Services to let them know that you are performing a repair.Request that Dell Technical Support Services suspend alerts for the expansion enclosure and ask for apre‐installation system check.Shutting Down the Storage System and Expansion EnclosuresIf the replacement component is not hot-swappable, use the Dell Storage Client to shut down thestorage system and expansion enclosures. Shutting down the storage system and expansion enclosuresresults in a system outage, so plan to perform these procedures during a maintenance window.1. Before shutting down the storage system and expansion enclosures, make sure you identify thefailed part.2. From the Actions menu, select System→ Shutdown/Restart. The Shutdown/Restart dialog boxappears.3. Select Shutdown and click OK.4. When the storage system and expansion enclosures are shut down, switch off both power switchesand unplug the power cables from the expansion enclosure.16 Replacing SC180 Components