Front

central processing unit (CPU)

Back

A computer that receives sensor data, analyzes that data and sends out orders to actuators to do the work. A CPU executes a program that directs the functions of the control system by semiconductor switching.

Front

commissioning

Back

The process of confirming, testing and starting up new devices.

Front

corrective maintenance

Back

The process of repairing a device after a failure has already occurred.

Front

direct current (dc)

Back

Current flow in only one direction.

Front

Electrically erasable programmable read-only memory (EEPROM)

Back

A type of memory that can be erased and reprogrammed. An EEPROM chip on a computer board is read-only memory (ROM).

Front

Electromechanical device

Back

A mechanical device that is electrically operated.

Front

Energy utilization index (EUI)

Back

An energy usage comparison for buildings, expressed in British thermal unit (Btu) per gross square foot. It compares energy consumption from one building to another.

Front

Ethernet

Back

A system for managing computer networks.

Front

Feedback

Back

A measurement of the result of an action performed by the controller.

Front

Light-emitting diode (LED)

Back

An LED display provides the operator with error codes and other information about the condition of the control system.