Duration: 5-8 Hours | |
Schedule: Online | |
Level: Beginner | |
Rs: 64,000 |
Electrical Hazards with examples: electric shock, arc flash events, working at heights, working in confined spaces, fire and explosion, mechanical hazards
Common electrical equipment and hazards posed
Arc Flash and its Effects
Reasons for arc flash events
What really happens in an arc flash event?
Insulation failure/violation of clearances
Arc flash mechanism
Impact on equipment
Hazards to personnel in the vicinity
Burns
Organ damage due to pressure wave
Hearing damage
Shrapnel effects
Fundamentals of Power Systems
Configurations
Equipment used
System earthing and its role
Protective earthing and its role
Faults and types of faults
Bolted faults and arc faults
Calculation of Fault Currents
Fundamentals of short circuit calculations
Simplifying assumptions
Ohmic impedance and per unit impedance
Infinite bus
Base KVA of a system and its use in calculations
Network theorems commonly used
Equivalent diagrams
Fault calculation approach for a simple system
Earth faults and the importance of system earthing
Mitigation of fault levels in a system
Protection in Power Systems
Fundamentals of power system protection
Protection attributes
Protective devices (fuses, built-in release and relays)
Time-current characteristics
Impact of bolted faults on tripping time
I2t: the important factor in deciding the hazards of faults
Commonly used protection approaches
Arc Flash Studies – Codes and Standards
OSHA 29 C FR – part 1910
National Electrical Code N FPA 70E – standard for electrical safety in the workplac
IEEE Standard 158
Definitions used in arc flash study
Arc Flash Study Detailed Procedure
Flash protection approach boundar
Detailed arc flash stud
Calculation of working distance and flash boundary as per IEEE Standard 1584
Data Collection and System Modeling
Data for calculation of fault currents
Modes of operation
Lower short circuit conditions with long tripping times
Determining Arc Flash Hazard Risk Category
Detailed examples and exercises simplified tables approach
Matrix table
Single line diagram approach
Short circuit study report coordination
Hazard risk category for metal-clad switchgear 1kv and above
NFPA 70E table 130
Reducing Arc-Flash Hazard
Mitigation of energy by reduced short circuit current and faster protection
Overvoltage protection to reduce insulation failure risk
Reducing the risk of arc flash by better equipment design (clearances, creepage, insulation)
Providing arc vents to direct arc away from operator
Containing internal arc flash by switchgear that is arc resistance
Avoid local operations and live work
Better maintenance practices
Insulation status and PD monitoring
Contacts and joint status-monitoring through thermography
Personal Protective Equipment Made of FR Clothing
The evolution of Flame Resistant (FR) fabrics
The various types of FR fabrics that are available in the marketplace
FR fabrics and the effects of undergarments
Limitations of FR fabrics
Test method ASTM F 1959
Garment construction standard ASTM F 1506-02a
Project Work
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