Glossary

Air Handling Unit - A device used to regulate and circulate air as part of a heating, ventilating, and air-conditioning system.

Building Automation System - A centralized system that controls and monitors building equipment such as HVAC, lighting, and security.

British Thermal Unit - A unit of heat energy equal to the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

A machine that removes heat from a liquid via a vapor-compression or absorption refrigeration cycle, used to cool buildings.

Computer Room Air Conditioning - Precision cooling units designed specifically for data center environments.

Electrical load that must be continuously powered to prevent data loss, equipment damage, or safety hazards.

Data Center - A facility used to house computer systems and associated components, such as telecommunications and storage systems.

A heat exchanger that uses ambient air to cool a fluid, typically water or glycol solution.

Emergency Power Off - A safety mechanism that allows for the immediate shutdown of electrical power in an emergency.

A machine that converts mechanical energy into electrical energy, used as backup power in data centers.

The aisle where hot exhaust air from IT equipment is contained and directed to cooling systems.

Heating, Ventilation, and Air Conditioning - The technology of indoor environmental comfort.

Kilowatt - A unit of power equal to 1,000 watts, commonly used to measure electrical power consumption.

Megawatt - A unit of power equal to 1,000,000 watts or 1,000 kilowatts.

A redundancy configuration where there is one additional component beyond what is required for normal operation.

Power Distribution Unit - A device for distributing electric power to multiple devices, typically rack-mounted in data centers.

Power Usage Effectiveness - A metric used to determine the energy efficiency of a data center, calculated as total facility power divided by IT equipment power.

A standardized frame or enclosure for mounting multiple electronic equipment modules, typically 19 inches wide.

The duplication of critical components or functions of a system to increase reliability and availability.

Service Level Agreement - A contract between a service provider and a customer that defines the level of service expected.

Uninterruptible Power Supply - An electrical apparatus that provides emergency power when the main power source fails.

Variable Air Volume - An HVAC system that varies the airflow at a constant temperature to meet heating and cooling demands.