Hardware replacement guidelines Page 21 of 362Hardware replacementDuring replacement procedures:• Turn off the circuit breaker or switch for a module power supply beforethe power supply is removed or inserted.• In AC-powered systems, capacitors in the power supply must discharge.Wait five full minutes between turning off the circuit breaker andremoving the power supply from the module.• Software disable cards, if applicable, before they are removed orinserted.• Hardware disable cards, whenever there is an enable/disable switch,before they are removed or inserted.• Return defective or heavily contaminated cards to a repair center. Do nottry to repair or clean them.Data disksFollow the precautions below to avoid damaging disks:• Handle only the hard surface; never touch the recording surface.• Keep disks away from strong magnetic fields.• Avoid exposing disks to extreme heat, rapid changes in temperature, orhigh humidity.• Store disks in a suitable container.To install a disk, make sure the arrow on the label is pointing up and therounded corner is on the bottom on the right-hand side.CAUTIONThe disk drive can be damaged if an upside-down disk is forced intothe slot. If there is significant resistance when you try to insert a disk,remove the disk and check the position.
