Definitions cont'd - hdbk10920298

DOE-HDBK-1092-98

Unstable material--The term means earth material, other than running, that because of its nature or

the influence of related conditions, cannot be depended upon to remain in place without extra support,

such as would be furnished by a system of shoring.

Vault--The term means an enclosure above or below ground which personnel may enter and is used

for the purpose of installing, operating, and/or maintaining equipment and/or cable.

Voltage--The term means the effective (rms) potential difference between any two conductors or

between a conductor and ground. Voltages are expressed in nominal values. The nominal voltage of

a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose

of convenient designation. The operating voltage of the system may vary above or below this value.

Voltage of an effectively grounded circuit--The term means the voltage between any conductor and

ground unless otherwise indicated.

Voltage of a circuit not effectively grounded--The term means the voltage between any two

conductors. If one circuit is directly connected to and supplied from another circuit of higher voltage

(as in the case of an autotransformer), both are considered as of the higher voltage, unless the circuit

of lower voltage is effectively grounded, in which case its voltage is not determined by the circuit

of higher voltage. Direct connection implies electric connection as distinguished from connection

merely through electromagnetic or electrostatic induction.

DEFINITIONS APPLICABLE TO SECTIONS 1 THROUGH 10

Bay--One vertical 19" wide segment of a rack cabinet. Several bays can be joined together to form

a large rack cabinet.

Code of record--The code in effect at the time of design or installation. Unless required to correct

a known hazard or a major modification is being performed, installations in compliance with the code

of record, do not need to be upgrade to a later edition of the code unless so stated in the code.

Controlled access--If the chassis are screwed into the rack cabinet. Doors having latches can be

taken to mean the circuitry is controlled. Control of the access to the area in which the tester is located

is also a means of control. In this case the area must be identified.

Electroexplosive device--An explosive device detonated by an integral electrical component upon

application of a specified voltage/current pulse to that component.

Electromagnetic (EMR) field--Time varying distribution in some medium of electric and magnetic

forces.

Electromagnetic radiation--Emission of electromagnetic energy from an electrical source in a

portion of the radio frequency spectrum which may pose a threat to electroexplosive devices.

Emergency-shutdown pushbutton (E-stop)--A control device provided to automatically stop electrical

energy to devices in the area during an emergency.

B-38