CAUTION:Never remove the cover on a power supply or any part that has the followinglabel attached.Hazardous voltage, current, and energy levels arepresent inside any component that has this labelattached. There are no serviceable parts inside thesecomponents. If you suspect a problem with one of theseparts, contact a service technician.Statement 31:DANGERElectrical current from power, telephone, and communication cablesis hazardous.To avoid a shock hazard:To Disconnect:1. Turn OFF all power sources and equipment that is tobe attached to this product.For ac systems, remove all power cords from thechassis power receptacles for interrupt power at theac power distribution unit.For dc systems, disconnect dc power sources at thebreaker panel or by turning off the power source.Then, remove the dc cables.2. Remove the signal cables from the connectors.3. Remove all cables from the devices.To Connect:1. Turn OFF all power sources and equipment that is tobe attached to this product.2. Attach signal cables to the product.3. Attach power cords to the product.For ac systems, use appliance inlets.For dc systems, ensure correct polarity of -48 V dcconnections: RTN is + and -48 V dc is -. Earthground should use a two-hole lug for safety.4. Attach signal cables to other devices.5. Connect power cords to their sources.6. Turn ON all the power sources.Do not connect or disconnect any cables or perform installation,maintenance, or reconfiguration of this product during an electrical storm.Connect all power cords to a properly wired and grounded power source.Connect to properly wired power sources any equipment that will be attached to this product.When possible, use one hand only to connect or disconnect signal cables.Never turn on any equipment when there is evidence of fire, water, or structural damage.Disconnect the attached ac power cords, dc power sources, network connections,telecommunications systems, and serial cables before you open the device covers,unless you are instructed otherwise in the installation and configuration procedures.Connect and disconnect cables as described in the following table whenyou install, move, or open covers on this product or attached devices.To remove a 750-watt -48 V to -60 V dc power supply, complete the followingsteps:Procedure1. Read the safety information and installation guidelines, see “Safety” on pagevii and “Installation guidelines” on page 45.2. Turn off the server (see “Turning off the server” on page 41) and remove theperipheral devices cables, excluding the power supply cable. Disconnect allexternal cables from the server.Attention: When you handle static-sensitive devices, take precautions toavoid damage from static electricity. For details about handling these devices,see “Handling static-sensitive devices” on page 46.288 System x3850 X6 and x3950 X6 Types 3837 and 3839: Installation and Service Guide
