What is Load Study and Why it is required ?
An Arc Flash Hazard Study is an analysis and assessment of the arc flash and shock hazards at a facility. The purpose of the study is to calculate the Incident Energy and identify the appropriate level of Personal Protective Equipment (PPE) for the personnel at various locations throughout the facility. These locations include switchgear, switchboards, substation, panel-boards, motor control centers, and industrial control panels. The arc flash study is a combination of a short circuit study and protective device coordination study. Both these studies must be completed before an Arc Flash Hazard Study can be done. The bolted three-phase current (short circuit current) is needed at each location as well as the upstream device operating time (protective device coordination study) for the reduced arcing fault current. The arc flash study will determine energy levels, boundary distances, and assists the owner in complying with the NFPA guidelines that are enforced by OSHA inspectors.
The result of the Arc Flash Study will include the following:
1) Short Circuit Current Values
2) Protective Device Settings (Protective Device Coordination Study)
3) Arc Flash Incident Energy Levels
4) Boundary Distances for
a) Arc Flash Protection
b) Limited Approach
c) Restricted Approachd) Prohibited Approach
5) Personal Protective Equipment (PPE)
6) Arc Flash and Shock Hazard Warning Labels (listing items #3 and #4a-d) for select equipment.
7) Complete report including
b) Executive Summary
c) Short Circuit Study
d) Short Circuit Equipment Summary Sheets
e) Protective Device Coordination Study
f) Protective Device Setting Sheets
g) Time Current Curves
h) Arc Flash and Shock Hazard Study
i) Arc Flash Calculations