This thread is where general discussions can be held about electrode configurations.

HOA ?

The IEEE 1584-2018 provides limited examples of the application of the HOA, VOA, VCB, VCBB, and HCB electrode configurations to medium voltage (>1kV and <15 kV) equipment. There are a couple follow up questions that could help clarify the application of the standard.

• Can the IEEE committee provide videos of the HOA, VOA, VCB, VCBB, and HCB tests on medium voltage (>1kV and <15 kV) equipment?
• If the arc is created on the VCB, could a HCB event occur?
• If the fault occurs in the middle of the vertical terminals (as circled in blue below in Figure G.40), would the arc go to the end of the conductive material (representing a VCB arc) or stay at the location that the arc was started (producing a HCB arc)?
• If the fault occurs in the middle of the vertical terminals (as circled in blue below in Figure G.40), would the arc go to the end of the conductive material (representing a VCB arc) if the terminals were longer in length?


• Based on the description and figures within G.4 of the IEEE 1584-2018, would the application of the standard for HOA and VOA arcs be based on the relative electrode direction (Horizontal electrode configurations – HOA, and Vertical electrode configurations – VOA)? For example in the picture, would a Horizontal electrode configuration be assume as the direction of the energized material is pointing towards the worker/sensor?
o Is it reasonable to assume both HOA and VOA are present if the electrode has a bend or has a variety of protrusions/shapes?
o How would the equipment manufactures modify the equipment to ensure the arc would go vertical away from the worker?