Silicon Graphics SGI Altix 450, User Manual

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8 007-4857-002
1: System Installation
Power Receptacle Verification
Ensure that a qualified technician installs the correct power receptacles. Your Altix 450 system
uses one or two single-phase power receptacles. For North American sites, the single-phase
receptacle is a 30-amp, 200- to 240-volt receptacle that has two phase sockets and one ground
socket. For international sites, the single-phase receptacle is a 32-amp, 200-volt receptacle that has
one phase socket, one neutral socket, and one ground socket. Note that the ground pin is slightly
longer than the other two pins on the North American plug.
Optional three-phase power distribution is available in systems mounted in 42U (tall) racks.
For North American sites, follow these steps to ensure that a single-phase power receptacle is
properly wired:
1. Set the voltmeter to a high AC voltage range.
2. Check the voltage between socket X and socket Y (see Figure 1-1). The meter should read
between 200 and 240 VAC.
3. Check the voltage between socket X and the ground socket. The meter should read
approximately 120 VAC.
4. Check the voltage between socket Y and the ground socket. The meter should read
approximately 120 VAC.
5. Check the voltage between the ground socket and an earth-ground location. The meter
should read 0 VAC.
6. Change the voltmeter to a low-resistance setting.
7. Measure between the ground socket and an appropriate earth-ground location and ensure that
resistance is less than 1 ohm.
8. Repeat steps 1 through 7 for any additional single-phase power receptacles.
Caution: If a voltage reading is incorrect, or if the resistance measured in step 7 is more than 1
ohm, contact a site-approved electrician. Do not proceed with the installation.
!