IBM Storage Networking SAN256B-7 Installation, Service And User Manual page 71

6. Attach the cable restraint cover under the power cord connector using its two torx head screws (see
Step "4" on page 46).
Note: This retainer cover protects the power cord from being accidentally unlatched and
disconnected from the power supply.
7. If connecting to an AC power source, use the following steps. (If connecting to a DC power source, go
on to Step "8" on page 47.)
a) Make sure that you observe the electrical caution and danger statements in "Safety precautions"
on page 7 when connecting this power supply.
b) Make sure that the AC power plug is attached to the power-source end of the HVAC/HVDC power
cord that meets your facility and local code requirements.
For more information on the HVAC/HVDC power cord available for these power supplies, see
"Using HVAC/HVDC power cords" on page 48.
DANGER: Make sure that the power source circuits are properly grounded, and then use
the power cord supplied with the device to connect it to the power source.
c) If connecting to an AC power source, connect to a power source with voltage of 200–277 VAC,
50/60 Hz (recommended).
Note: Use of a high-voltage line (200–277 VAC) is highly recommended because of better power-
conversion efficiency. For a "fully-loaded" chassis with maximum supported blades and optics,
two power supplies connected to 200–277 VAC are required for full N+N redundancy. For details
on power supplies required for operation and high availability, see "Power Supply Requirements"
and "Power Consumption" tables in the Appendix A, "Product specifications," on page 191.
DANGER: High Touch Current. Earth connection essential before connecting supply.
CAUTION: Use a separate branch circuit for each power cord, which provides redundancy
in case one of the circuits fails.
8. If connecting to an DC power source, use the following steps. (If connecting to a AC power source, go
to Step 7.)
a) Make sure that you observe applicable electrical caution and danger statements in "Safety
precautions" on page 7 when connecting this power supply.
Chapter 4. Initial setup and verification 47