Causes of electrical faults
A fault is not a natural occurrence. it is an unplanned event which occurs unexpectedly. Electrical faults in an electrical installation or piece of equipment may be caused byNegligence - that is lack of proper care and attention
Misuse - that is not using the equipment properly or correctly
Abuse - that is deliberate ill treatment of the equipment
By picture presentation we describe
7 Possible points where electrical faults occur
Point 1- Fault occur in wiring system
All cable connections must be made mechanically and electrically secure . They must also remain accessible for future inspection , testing and maintenance
The only three exception to this rule are when
1. Underground cables are connected in a compound filled or encapsulated joint.
2. Floor warming or ceiling warming heating system are connected to a cold tail.
3. A joint is made by brazing , soldering or compression tool.
Since they are accessible , cable inter connections are an obvious point of investigation when searching out the cause of a fault.
Point 2- Electrical faults also occur at cable termination
Flexible cords are delicate - has the terminal screw been over tightened , thus breaking the connection as the conductors flex or vibrate ?
Point 3-. Electrical faults also occur at accessories such as switches , sockets, control gear, motor contactors or motor contactors or at the point of connection with electronic equipment.
Socket outlets that have been used extensively and loaded to capacity in say kitchens, are another source of fault due to overheating or loose connections.
Point 4 - Fault occur on instrumentation panels either as a result of a faulty instrument or as a result of a faulty monitoring probe connected to the instrument . Many panel instruments are standard sizes connected to CTs or VTs and this is another source of possible faults of the types decribed in points 1 through 3.
Point 5 - Fault occur in protective devices for the reasons given in points 1 through 3 above, but also because they may have been badly selected for the job in hand and do not offer adequate protection or discrimination.
Point 6 - Faults often occur in luminaires (light fittings) because the lamp has expired.
Discharge lighting also require a starter to be in good condition, although many fluorescent luminaires these days use starter less electronic control gear.
Point 7 - Electrical faults occur in electrical components , equipment and accessories because these all have points at which electrical connections are made . These are
- Motors
- Stators
- Panels
- Switch gear
- Controlgear
- Distribution panel