IBM System Storage Subsystem DS5020 - Manual (Page 53)

These levels are measured in controlled acoustical environments according to ISO
7779 and are reported in accordance with ISO 9296. The declared sound power
levels indicate an upper limit, below which a large portion of machines operate.
Sound pressure levels in your location might exceed the average 1-meter values
stated because of room reflections and other nearby noise.
Electrical requirements
This section provides information regarding site power and wiring, storage
subsystem power requirements, and power cord routing instructions.
Consider the following information when preparing the installation site:
v Protective ground – Site wiring must include a protective ground connection to
the ac power source.
Note: Protective ground is also known as safety ground or chassis ground.
v Circuit overloading – Power circuits and associated circuit breakers must provide
sufficient power and overload protection. To prevent possible damage to the unit,
isolate its power source from large switching loads (such as air conditioning
motors, elevator motors, and factory loads).
v Power failures – If a total power failure occurs, the unit automatically performs a
power-up recovery sequence without operator intervention after power is
restored.
Table 11. DS5020 ac power requirements
Low Range High Range
Nominal Voltage 90 to 136 VAC 198 to 264 VAC
Frequency (Hertz) 50 to 60 Hz 50 to 60 Hz
Idle Current 3.53 A a 2.08 A b
Maximum Operating Current 3.71 A a 2.04 A b
Maximum Surge Current 5.04 A a 2.67 A b
a. Typical voltage: 120 V ac, 60 Hz, assumes 72% power-supply efficiency and 0.99 power
factor
b. Typical voltage: 240 V ac, 60 Hz, assumes 72% power-supply efficiency and 0.99 power
factor
Power and site wiring requirements
The storage subsystem uses wide-ranging redundant power supplies that
automatically accommodate voltages to the ac power source. The ac power
supplies operate within the ranges specified in Table 11. The ac power supplies
meet standard voltage requirements for both domestic (inside USA) and
international (outside USA) operation. They use standard industrial wiring with
line-to-neutral or line-to-line power connections.
The agency ratings for the DS5020 storage subsystem are 6 amps at 100 VAC and
2.5 amps at 240 VAC. These are the overall maximum operating currents for the
DS5020 storage subsystem with ac power supply and fan unit CRUs.
AC power recovery: After a total ac power failure, after normal power is restored,
the storage subsystem performs power-up recovery procedures automatically
without operator intervention.
Chapter 1. Introduction 23