| Terms | Term Description |
|---|---|
| Arc | Short-circuit inside the ASSEMBLY, resulting in a free burning arc within an ASSEMBLY. |
| Arc Free Zone | Zone within the ASSEMBLY where it is not possible to apply an ignition wire without destroying the insulation on the conductors. |
| Arc Proof Zone | Zone where an ignition wire can be applied and fulfilling all relevant criteria for the assessment of the test. |
| Arc Proof ASSEMBLY | Assembly consisting of arc free zones and/or arc proof zones. |
| Ip Arc | Permissible current under arcing conditions |
| t Arc | Permissible ac duration |
| Ipc Arc | Permissible conditional short circuit current under arcing conditions |
| Personal Protection | Ability of ASSEMBLY to provide Personal protection there by limiting risk of personal injury, which may be caused due to mechnical and thermal effects of Internal Arcing fault of ASSEMBLY. |
| 1st condition for personal Protection | Personal Protection due to Arcing fault inside ASSEMBLY, applies when doors and covers are closed and correctly secured. |
| ASSEMBLY Protection | ASSEMBLY Protection from Arcing fault is ability of Assembly to limit effects of Internal Arcing fault to the zone/Compartment where the Arc fault began, there by ensuring protection to other healthy Assembly zones. |
| Incident Energy Arc Flash Energy | The amount of thermal energy impressed on a surface, at certain distance from the source, generated during an electrical arc event |
| Arc Flash boundary | The distance from the source of the arc flash blast where the incident energy equals 1.2 cal/cm2 |
What is Symmetrical components – Sequence Components ?
Unbalanced 3 phase system can be resolved into 3 balanced systems – Positive, Negative and Zero Sequence Symmetrical components.