Arc Flash Causes
Two most common arc flash causes are carelessness as human error and existing circuit-breaker failed to interrupt a short-circuit within electrical system. However, there are still several causes of arc flash and arc blast hazard that have the potential to cause disability and even death. Also we will discus in brief about arc flash location source, origin, place or point position where does arc flash event or incident may occur. In the previous article entitled Arc Flash: Definition, Hazards and Risks have been briefly reviewed understanding, danger and the level of risk associated with arc flash. This article will discuss more in depth the analysis of what common root cause for arc flash sources event. In short, arc flash is caused by simple matter and sometimes even trivial things within electrical power system in live condition.
The following are the factors that cause arc flash:
- Failed to interrupt the short-circuit due to poor circuit-breaker maintenance
- Accidental contact due to carelessness
- Objects or animals accidentally hit or pass through over open conductors
- Moisture due to condensation
- Corrosion
- Excessive dust
- Bad or loose connections or joints
- Water or liquid enters into electrical equipment
- Static electricity or electrostatic
- Component material failure such as aging or insulation damage
- Damaged working tools
The various causes of arc flash above can be categorized as technical causes and non-technical causes. This article will analyze several things which according to facts and data are the most common causes of arc flash.
———————————————
Arc Flash Location
As we know, arc flash events are closely related to short circuit fault. The magnitude of the short circuit current depends on various factors, including system voltage, source and component impedance, and fault location. Likewise with arc flash, incident energy is also determined by the location of an arc flash event.
There are several point sources locations or positions for or place where arc flash events may occur. They are:
- Electrical panels
- Switchboard
- Fused switch
- Metal clad switchgear (MCS)
- Motor control center (MCC)
- Transformer
- Damaged cable
———————————————
Carelessness –The Most Dominant Cause
Carelessness that led to accidental contact is most common cause of arc flash event when working in live condition. Even the senior electric technicians sometimes make unintentional carelessness. For example, technicians working on live electric panels accidentally drop work tools such as insulated screwdrivers or wrenches into bus-bar of the panels. This may cause a short-circuit between the live conductor or between the conductor and the body of panel that connected to the ground. The cause of arcs with high energy incidents is when carelessness causes a bolted short-circuit, a condition in which all three conductors in a 3-phase system are accidentally connected.
Other most common causes of arc flash are:
- Fail to break short-circuit
- Water or liquid enters into live electrical equipment
- Animals are accidentally passing on open conductors
———————————————
Contact Omazaki Consultant if you need a consultant to analyze the root causes of arc flash and arc blast, or arc flash location and position point, arc flash source or origin, that might occurred within in your electrical system throughout Indonesia.
———————————————
Related Articles
- Arc Flash: Definition, Hazards and Risks
- Arc Flash Calculation Methods
- Arc Flash Boundary and Requirements of Personal Protective Equipment (PPE)
- Arc Flash Study & Assessment
- Electric Shock Protection Study
- Power System Study and Analysis
- Short Circuit Study and Analysis
———————————————
References
———————————————