HP Superdome SX2000 Generic Site Preparation Guide, Fourth Edition - Page 38

maximum input current NEBS The operating current of the product equal to the maximum load divided by the minimum input voltage. Network Equipment Building Standards. A set of safety guidelines. All electronic equipment has the potential to interfere with other electronic equipment. Interference can be caused by electromagnetic radiation, the grounding system, the electrical power connection, excessive heat or blocking the natural airflow, and connecting wires or cables. The Federal Communications Commission (FCC) regulates a portion of this problem through Part 15 of its rules and regulations. Even more stringent than the FCC Part 15 requirements, NEBS covers a large range of requirements, including criteria for personnel safety, protection of property, and operational continuity. The documents cover such physical requirements as space planning, temperature, humidity, fire, earthquake, vibration, transportation, acoustics, air quality, and illumination. The documents also cover such electrical criteria as electrostatic discharge (ESD), electromagnetic interference (EMI), lightning and AC power fault, steady state power induction, corrosion, DC potential difference, electrical safety and bonding, and grounding. O-R PCA PCI PICMG power factor RMS Printed Circuit Assembly, also referred to as a printed circuit board (PCB). Currently, the most popular local I/O bus, the Peripheral Component Interconnect (PCI) bus was developed by Intel® and introduced in 1993. A consortium of companies involved in utilizing PCI for embedded applications. The PCI Industrial Computer Manufacturers Group (PICMG) controls the PICMG specification. The ratio of true power to apparent power in an AC circuit. In power conversion technology, power factor is used in conjunction with describing the AC input current to the power supply. Root mean square. Term that refers to the most common mathematical method of defining the effective voltage or current of an AC wave. To determine RMS value, three mathematical operations are carried out on the function representing the AC waveform: (1) The square of the waveform function (usually a sine wave) is determined. (2) The function resulting from step 1 is averaged over time. (3) The square root of the function resulting from step 2 is found. S-T theoretical maximum power consumption tonnage true power typical input current typical power consumption Maximum wattage of a given configuration, assuming worst-case conditions (thermal tolerances, work loads, and so forth) on all system components. It is extremely unlikely that any customer will experience this level of power consumption. The unit of measure used in air-conditioning to describe the heating or cooling capacity of a system. One ton of heat represents the amount of heat needed to melt 1 ton (2,000 lb) of ice in 1 hour and 12,000 Btu/h equals 1 ton of heat. In an AC circuit, true power is the actual power consumed. It is distinguished from apparent power by eliminating the reactive power component that may be present. The operating current of the product measured using a typical load and target voltage. Represents the expected power consumption of a given configuration. The typical value is the approximate power consumption that a customer will most likely experience and can use for power budgeting purposes. U-Z vapor seal A vapor seal is an essential part of preventing moisture infiltration into or migration out of a critical space, such as a data processing center or other room that contains sensitive electronic instrumentation. Essentially, a vapor seal is a barrier that prevents air, moisture, and contaminants from migrating through tiny cracks or pores in the walls, floor, and ceiling into the critical space. Vapor barriers can be created using plastic film, vapor-retardant paint, vinyl wall coverings, and vinyl floor systems, in combination with careful sealing of all openings (doors and windows) into the room. 38 Glossary