IBM DS4700 EXPRESS, Installation, User'S, And Maintenance Manual

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Table 15. Temperature and humidity requirements for storage subsystem in a Telco/NEBS-3
compliant environment (continued)
Condition Parameter Requirement
Relative humidity
1
(no
condensation)
Operating range 5% to 85%
Short-term
2
5% to 90% (not to exceed
0.024 kg water/kg of dry air)
Notes:
1. In a Telco/NEBS-3 compliant environment, conditions are measured at a location 1.5 m
(59 in.) above the floor and 400 mm (15.8 in.) in front of the equipment.
2. Short-term refers to a period of not more than 96 consecutive hours and a total of not
more than 15 days in one year. (This refers to a total of 360 hours in any given year, but
no more than 15 occurrences during that one-year period.)
Altitude
Table 16 lists the acceptable altitudes for operating, storing, and shipping the
DS4700 Express.
Table 16. DS4700 Express altitude ranges
Environment Altitude
Operating 30.5 m (100 ft.) below sea level to 3000 m
(9842 ft.) above sea level
Storage 30.5 m (100 ft.) below sea level to 3000 m
(9842 ft.) above sea level
Transit 30.5 m (100 ft.) below sea level to 12,000 m
(40,000 ft.) above sea level
Airflow and heat dissipation
Figure 15 shows the intended airflow for the DS4700 Express. Allow at least 30
inches in front of the storage subsystem and at least 24 inches behind the storage
subsystem for service clearance, proper ventilation, and heat dissipation.
Table 17 on page 26 lists the KVA, watts, and Btu calculations. These values
assume the power supplies have a 73 percent efficiency and a power factor of 0.99.
77027-02
Figure 15. DS4700 Express airflow
Chapter 1. Introduction
25