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### IEEE 1584-2018 Arc Flash Procedure Equations and Calculations

Electrical and Electronics Design and Engineering

IEEE 1584-2018 Arc Flash Equations and Calculations

Arc Flash Hazard Calculations Procedure and Considerations For Medium Voltage System

Arc flash is defined as the sudden release of energy due to uncontrolled electric arc which is the product of short circuit current and arc duration. Typically there is a plasma cloud created when metals vaporize and gas temperatures can reach 35,000°F.

Note that this webpage is an overview and only qualified professionals should approve design and analysis of Arc Flash Equations and Calculations per. IEEE 1584-2018.

Arc Flash Causes:

• Human error (the #1 cause)
• Accidental contact by person or tool (engineers are not exempt)
• Incorrect assembly/repair
• Incorrect tool use
• Mechanical failure
• Lack of maintenance
• Material defect
• Foreign object intrusion
• Dust/debris
• Water
• Animals
• Stressed/weakened components

Standards of consideration

• OSHA 29 CFR 1910 (revised 2014)
• Effective April 1, 2015
• NEC - NFPA 70-2017 (revised every 3 years)
• NFPA 70E-2018 (revised every 3 years)
• IEEE 1584-2018 superceding IEEE 1584-2002

IEEE 1584-2018

Please note there there are several possible paths in an analysis of Arc-Flash Incident Energy of a voltage system. Consult IEEE-1584-2018 for details and procedures.

The following is the general procedure/steps for an incident energy and arc-flash boundary calculation for a medium-voltage system:

Step 1)

Define system and input parameters:

Step 1:

Calculate: Intermediate Arcing Current Iarc_600, Iarc_2400, or Iarc_14300 (kA)

Step 2:

Calculate Final Arcing Current Iarc (kA) and determine arc duration T ( ms ) from fuse, etc. data.

Step 3:

Enclosure Size Equivalent Height and Width Correction Factor CF, ESS

Step 4:

Intermediate Value of Incident Energy Earc_600, Earc_2400, or Earc_14300 (J / cm2)

Step 5:

Final Value of Incident Energy E E600, E2700, E14300 and E≤600 (J / cm2)

Step 6:

Intermediate Value of Arc-Flash Boundary AFB600, AFB2400, or AFB14300(mm)

Step 7:

Final Arc-Flash Boundary AFB1, AFB2 AFB3, and AFB (mm)

Step 8: (To account for the arcing current variations)

Arcing Current Variation Correct Factor ( 1 - 0.5 VarCf )

Step 9:

Final Values of Arcing Current using the Correction Factor Iarc (kA) and T (ms)

Step 10:

Repeat Step 4 using Reduced Arcing Current Earc_600, Earc_2400, or Earc_14300 (J / cm2)

Intermediate Value of Incident Energy

Step 11

Repeat Step 4, Reduced Intermediate Currents

Intermediate Value of Incident Energy Earc_600, Earc_2400, or Earc_14300 (J / cm2)

Step 12

Repeat Step 5 using the reduced arcing currents.

Final Value of Incident Energy E E600, E2700, E14300 and E≤600 (J / cm2)

Step 13

Repeat Step 6 using the reduced arcing currents.

Intermediate Value of Arc-Flash Boundary AFB600, AFB2400, or AFB14300(mm)

IEEE 1584-2018

Verify results and send feedback if a discrepancy is found.