IBM 7133 Series Service Manual

AC and DC Input-Voltage Requirements| Environment (Models 010 and 020)Fan-and-Power-SupplyAssembly TypeVoltage Frequency220 V 90 to 260 V acor240 to 375 V dc47 to 64 Hz–| −48 V| −43 to −60 V dc| –OperatingEnvironmentNonoperatingEnvironmentStoringEnvironmentShippingEnvironmentAir temperature 10°C to 40°C(50°F to 104°F)10°C to 52°C(50°F to 125°F)1°C to 60°C(34°F to 140°F)–40°C to 60°C(–40°F to 140°F)RelativeHumidity8% to 80%noncondensing8% to 80%noncondensing5% to 80%noncondensing5% to 100%condensing butnot precipitatingMaximum wet bulb 27°C (80°F) 27°C (80°F) 29°C (84°F) 29°C (84°F)| Notes:| 1. Each 7133 rack-mounted unit requires an airflow of 1.56 cubic meters/minute (55 CFM). When racks| containing many 7133 units are to be installed together, the following requirements must be met to| ensure that the 7133 units are adequately cooled:| The airflow enters at the front of the rack and leaves at the back. To prevent the air that is| leaving the rack from entering the intake of another piece of equipment, racks should be| positioned in alternate rows, back-to-back and front-to-front.| The front of racks should be positioned on floor-tile seams, with a full line of perforated tiles| immediately in front of the racks. Each perforated tile should have an air flow of at least| 11.34 m/min (400 CFM). The underfloor temperature must be at most 15°C (60°F).| Where racks are in rows front-to-front or back-to-back, there should be a gap of at least 1220 mm| (48 in) separating the rows.| To ensure proper air flow within each rack, the rack filler plates must be installed in unused| positions. Also, all the gaps in the front of the racks must be sealed, including the gaps between| the 7133 units.| 2. The recommended operating temperature is 22°C (72°F) or lower. At lower temperatures, the risk of| failure in the unit is reduced. If the operating temperature is above 22°C (72°F) for long periods of| time, the unit is exposed to a greater risk of failure from external causes.Chapter 1. Reference Information 1-33