4: Powering-On The Subsystem; Power System; Ac Power Distribution Units; Chapter 4, Powering-On The Subsystem - StorageTek L180 Installation Manual

Powering-On the Subsystem
This chapter contains the procedures for connecting the power cable and
powering-on the library and tape drives.
CAUTION:
Potential equipment damage: Do not connect the library's power cable to
the power source until you are told to do so in this manual. Make sure
that the circuit breakers at the library power supply and for the power
source are turned off.

Power System

The library power system consists of:
• One or two AC power distribution units (PDUs)
• One or two DC power supplies that provide voltage to the library
• An optional uninterruptible power supply

AC Power Distribution Units

Each power distribution unit (PDU):
• Operates within 100 to 127 VAC or 200 to 240 VAC at 50/60 Hz
• Distributes AC voltage to a library DC power supply
• Protects the library from overcurrent by circuit breakers
The standard PDU supplies AC voltage to the robotics and drive column.
An optional PDU can supply power for redundancy.
Be aware that each PDU in a newer library supplies power to the robotics and
half of the drives. So when the library has two PDUs (and a drive column with
two power cords), connect each PDU to a separate, branch AC circuit.
If you are installing multiple drives in the library—and the library is a newer
model with two power cords to the drive column—StorageTek recommends
that you place some drives in the upper five slots and some drives in the lower
five slots in the drive column.
With this configuration and with each PDU connected to a separate AC circuit,
if one PDU loses power, then the customer still has some operational drives as
well as operational library robotics.
95896 Eleventh Edition
StorageTek Proprietary
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