IBM DS4700 manual Altitude, Airflow and heat dissipation, Environment

Table 15. Temperature and humidity requirements for storage subsystem in a Telco/NEBS-3 compliant environment (continued)

Condition	Parameter	Requirement
Relative humidity1 (no	Operating range	5% to 85%
condensation)
	Short-term2	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

Operating

Storage

Transit

Altitude

30.5m (100 ft.) below sea level to 3000 m (9842 ft.) above sea level

30.5m (100 ft.) below sea level to 3000 m (9842 ft.) above sea level

30.5m (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.

Figure 15. DS4700 Express airflow

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.

Chapter 1. Introduction 25