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IEEE 1584-2018 Electrode Configuration in Equipment

Electrical and Electronics Design and Engineering

IEEE 1584-2018 Electrode Configuration in Equipment

The equipment conductor and enclosure arrangement that most closely resembles the actual electrode configuration(s) must be identified to complete Arc Flash Design Calculations. The equipment such as switchgear, panelboards, and motor control centers may contain conductors arranged in similar manner as the test setup electrode configurations presented in the table below. Locations within a piece of equipment may contain conductor arrangements similar to more than one electrode configuration. As an example, a panelboard may contain both VCB and VCBB electrode configurations. Other types of equipment such as switchgear, disconnect switches, and switchboards may have other electrode configurations such as HCB depending on the bus and conductor arrangement.


Arc Flash Hazard Calculations Procedure and Considerations For Medium Voltage System 

Additional guidance regarding the selection of VCB, VCCB, HCB, HOA, and VOA is available in IEEE 1584-2018 Annex C and G.2.

Electrode Configuration
VCB -Vertical conductors/electrodes in a metal box/enclosure (also in 2002 Edition). With the original vertical electrode configuration, when an arc flash occurs in an enclosure, the arc is driven away from the source, down the electrodes, toward the bottom of the enclosure and out of the front.
VCBB - Vertical conductors/electrodes terminated in a metal box/enclosure's insulating barrier. If vertical electrodes are terminated into an insulating barrier, research has demonstrated the arc hits the barrier, and the plasma cloud is directed more toward the enclosure opening.
HCB - Horizontal conductors/electrodes in a metal box/enclosure. When the electrodes are placed horizontally, the arc plasma is directed from the electrode ends outward.
VOA - Vertical conductors/electrodes in open air (also in 2002 Edition). Tests were conducted in open air using the original vertical configuration in open air.
HOA - Horizontal conductors/electrodes in open air. Tests were conducted in open air using a new configuration with horizontal electrodes in open air.

IEEE 1584-2018

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