Problem and Consequences in Electrical System and their Correction

Introduction to Electrical Faults

Fault in electrical equipment or apparatus is defined as an imperfection in the electrical circuit due to which current is deflected from the intended path. In other words, the fault is the abnormal condition of the electrical system which damages the electrical equipment and disturbs the normal flow of the electric current.

Types of Faults

There are several types of faults that 

1. Short-circuit fault:  A short circuit is when there is a low resistance connection between two conductors supplying electrical power to a circuit. This would generate an excess of voltage streaming and cause an excessive current flow in the power source. The electricity will flow through a ‘short’ route and cause an electrical short circuit.                                  This occurs when two or more conductors in a circuit come into contact with each other, causing a sudden surge of current. 

There are two types of Electrical Short Circuits:

Normal Short Circuit

This is when a hot wire carrying current touches a neutral wire. When that happens, the resistance will go down instantly and a large volume of current will flow through an unexpected pathway.

Ground Fault Short Circuit

Ground fault short circuit occurs when the hot wire carrying current comes into contact with some grounded portion of the system. It can be a grounded metal wall box, bare ground wire or a grounded portion of an appliance

What Are Main Causes of Electrical Short Circuit?

The main causes of Electrical Short Circuit are:

Faulty Circuit Wire Insulation :If the insulation is damaged or old, it may allow the hot wires to touch with neutral. This will cause a short circuit.

Age of the wire, nails or screws can damage the insulation and allow short circuit. There is a risk of pests of gnawing the insulation and exposing the wire conductors too.

Loose Wire Connections: If there are any loose wire connections or attachments, it will allow the live and neutral wires to touch. If you see loose wire connections, try to fix them by re connecting it and ensure it is tighten.

Faulty Appliance Wiring: If you plug an appliance into a wall socket, its wiring essentially becomes an extension of the circuit. Therefore, if there are any problems in the appliance wiring, it will become circuit problems.Short circuits can occur in the power cords, plugs or inside the appliance. 

Pets Chewing Down the Wires: Pests like rats, cats, and squirrels chewing on electrical wires is one of the leading causes of short circuits. This problem is widespread in places where there are rodents,the wiring may be more exposed. These rodents can cause a lot of damage to the  electrical system.

Electrical Wiring Coming Into Contact With Moisture :When water or another type of fluid comes into contact with electrical wiring, it can cause a short circuit. This is because the water can conduct electricity, which can cause the current to flow through the water and into the ground. This can damage the wiring and potentially cause a fire.

Damaged Outlets, Switches, and Electrical Appliances:If the lights are flickering or someone  has to jiggle the plugs to keep them working, it may be time to replace the outlets, switches, and lights. Old or damaged electrical devices can cause a short circuit, a dangerous situation where electrical current bypasses its intended path.

Nails or Screws in Live Wire: Nails or screws pierce through walls and come into contact with live electrical wires can cause a short circuit. This is a serious hazard that can lead to fires and electrocution.

Signs of Short Circuit

Burn Marks or Burning Smell From Outlets:  One sign of a short circuit is if the outlet has burn marks or emits a burning smell. An overloaded circuit usually causes this. It can be a fire hazard.

Buzzing & Popping Sound From the Outlet: Another sign to look for is if you hear a buzzing or popping sound from the outlet. An overloaded circuit can also cause this, and it’s definitely a cause for concern.

Sparks Coming Out From the Circuit: Sparks emitted from the outlet also indicate an electrical short circuit. If you see sparks, it means that there is an excessive amount of current flowing through the circuit, which can be dangerous.

How to Prevent an Electrical Short Circuit?

Circuit Breakers or Fuses:A circuit breaker is a switching device in a circuit that interrupts an abnormal flow of current. It uses an internal system of springs or compressed air to sense any changes in the current flow. It will ‘break’ the circuit open and cut the flow of current.A fuse is a device that provides overcurrent protection. It has a metal strip or wire that melts when a large amount of current flows through it. This interrupts the circuit.

Ground-Fault Circuit Interrupters (GFCIs): GFCI works by comparing the amount of current flowing in and out of a circuit. If there is a ground fault or imbalance between the currents flowing in and out, the GFCI will shut off electrical power.

Arc-Fault Circuit Interrupters (AFCIs): An AFCI breaks the circuit when it detects an electric arc in the circuit. It helps in preventing electrical fires.

              Consequences of short circuit

The effects of a short circuit can vary depending on the severity and duration of fault, it can potentially damage appliances, cause fires or explosions and create safety hazards.Appliances that are connected to the faulty circuit may stop functioning or may experience damage, and there may be a sudden power outage in the affected area.

 Electrical fire after short circuit in consumer unit, burnt wiring and circuit breakers in switchboard

Open Circuit Fault:  This occurs when there is a break in the circuit, which prevents current from flowing.

 Causes of Open Circuit Fault

 Broken wires: A wire may break due to mechanical stress,corrosion,or age, causing an open circuit in the system.

Loose connection: Connection between wires or between wires and electrical components may become loose over time,resulting in an open circuit.

Damaged insulation: The insulation surronding a wire may become damaged due to heat,mechanical stress,or exposure to chemicals,leading to an open circuit

Faulty switches or relays: A faulty switch or relay can cause an open circuit by failing to close the electrical path.

Blown fuses: A blown fuse can cause an open circuit by breaking the electrical path when the current exceeds the fuse rating.

Effect of Open Circuit in an electrical system

No Power : In the case of an open circuit in a power supply line,the affected equipment or system will not receive any power,and will not be able to function.

      Correction of open circuit fault

Identify the open circuit: Use a multimeter or other diagnostic tool to identify the location of the open circuit. Look for any broken or disconnected wires,blown fuses,or other components that may be causing problems.

Replace or repair the faulty component: Once you have identified the faulty component, replace it as needed.This may involve replacing blown fuses.

Test the circuit: After replacing or repairing the faulty component,test the circuit to ensure that the open circuit has been resolved.Use a multimeter or other diagnostic tool to confirm that there is no longer a break in the circuit and that current is flowing properly.

Take preventive measures: To prevent future open circuit issues, make sure that all components are properly connected and secured, and that the wires are not subject to stress that could cause them to break or disconnect.

     Over voltage fault

Overvoltage can be caused by poor regulation of a power source from a utility company, oversized transformers, uneven or varying circuit loading, wiring errors, and electrical insulation or isolation failures

 Causes of Over voltage

1. Lightning strikes: Lightning strikes near power lines or electrical equipment can cause a sudden surge of voltage, which can lead to overvoltage.

2. Faulty voltage regulators: Voltage regulators are devices that regulate the voltage of an electrical system. Faulty voltage regulators can cause overvoltage by allowing the voltage to increase beyond the rated level.

3. Load shedding: Load shedding, which is the intentional reduction of electricity demand during peak periods, can cause overvoltage in the remaining parts of the electrical system.

4. Switching operations: Switching operations in the electrical system, such as switching off a large load or disconnecting a transmission line, can cause overvoltage due to the sudden change in the electrical load (Sudden interruption of heavy loads)

5. Reactive power compensation: Reactive power compensation is a technique used to improve the power factor of an electrical system. However, if not properly designed, it can lead to overvoltage.

6. Poor grounding: Poor grounding of electrical equipment can cause overvoltage by allowing voltage to accumulate on the equipment

Effect of over voltage in electrical system

Damage to electrical equipment: Overvoltage can damage electrical equipment such as transformers,motors by causing insulation breakdown,overheating,and other types of damage

Fire risk: Overvoltage can create a fire risk due to increased electrical current flowing through the system,which can cause overheating and potentially lead to electrical fires.

Power outages:  Over voltage can cause power outages by tripping circuit breakers, blowing fuses or causing other types of accidents.

Correction of Overvoltage 

Here are some ways to protect and correct overvoltage in an electrical system:      

1. Voltage Regulator: Voltage regulators are devices that maintain a steady voltage level in an electrical system by adjusting the voltage output. They are commonly used in power systems to ensure that voltage levels remain within the acceptable range.

2. Overvoltage Protection Relays: Overvoltage protection relays are devices that monitor the voltage level in an electrical system and disconnect the power supply when the voltage level exceeds a certain threshold. This helps to prevent damage to equipment and ensure the safety of people working on or around the system.

3. Transient Voltage Suppressors: Transient voltage suppressors are devices that protect against overvoltage caused by transient voltage spikes. They work by absorbing the excess voltage and diverting it away from the electrical system.

  Undervoltage fault

This occurs when there is a sudden decrease in voltage in the system, which can cause equipment to malfunction and disrupt power supply.

Causes of under voltage fault

1. Overloaded System: An overloaded system can cause voltage drop due to the excessive load on the system. This can be caused by adding too many devices or equipment to the system, which can exceed the capacity of the system and cause the voltage to drop.

2. Faulty Transformers: Faulty transformers can cause voltage drop due to issues such as winding damage or insulation failure. This can cause the voltage to drop to an unacceptable level, leading to under voltage fault.

3. Voltage Regulation Issues: Voltage regulation issues can cause voltage fault when the voltage level is not properly regulated. This can be caused by faulty voltage regulators or issues with the power supply.

4. Voltage Sags and Swells: Voltage sags and swells can cause under voltage fault when the voltage level drops below or above the acceptable range. These voltage fluctuations can be caused by lightning strikes, power outages, or other disturbances in the power supply.

5. Cable Resistance: Cable resistance can cause voltage drop when the cables used in the electrical system are not properly sized or when there is a fault in the cables. This can cause the voltage to drop as the current flows through the cables.

Effect of under voltage fault

Under voltage in electrical equipment can have several negative consequences, including:

1. Reduced Performance: Electrical equipment such as motors, transformers, and lighting systems may not function optimally when operating under low voltage conditions. This can lead to reduced performance, decreased productivity, and increased downtime.

2. Overheating: When voltage levels fall below the designed range, electrical equipment may draw more current than it is rated for, causing overheating and potentially damaging the equipment.

3. Increased Wear and Tear: Under voltage can cause electrical equipment to work harder than normal, leading to increased wear and tear on the equipment’s components. This can result in premature failure of the equipment.

4. Data Loss:  Under voltage can cause disruptions in electronic devices such as computers and servers, leading to data loss and potentially damaging the equipment.

 Correction of under voltage

1. Regular maintenance: Regular maintenance of electrical systems and equipment can help prevent under voltage. This includes cleaning, testing, and inspecting components for signs of wear or damage.

2. Power conditioning:  Power conditioning devices such as voltage regulators,, and uninterruptible power supplies can help prevent under voltage by regulating voltage levels and protecting against power surges and spikes.

3. Load management: Overloading of electrical systems can cause under voltage. Proper load management, such as balancing loads and avoiding excessive use of equipment, can help prevent under voltage.

4. Voltage drop compensation:  Voltage drop can occur in long power cables, which can lead to under voltage. Voltage drop compensation methods such as increasing the cable size, using voltage boosters, and reducing cable length can help mitigate under voltage.

5. System upgrades:  Upgrading electrical systems, components, and equipment can help prevent under voltage by providing more efficient and reliable power.

Overcurrent fault

This occurs when there is a sudden increase in current in the system, which can cause damage to equipment and create safety hazards

  Causes of overcurrent

Short Circuit: A short circuit occurs when an electrical device forms an unintended path of low resistance.This can cause a surge of current that exceeds the capacity of the system,resulting in over current.

Overload:  Overload occurs when the current drawn by electrical devices exceeds the capacity of the system.This can be caused by connecting too many devices to a circuit,using devices with higher power requirements than the circuit can handle,or operating equipment at higher than recommended levels.

Faulty equipment: Faulty or damaged equipment can cause over current by drawing more current than the system is designed to handle.This can be caused by damaged insulation,loose connections, or other defects.

Lightning strikes: Lightning strikes can cause power surges that result in over current

Improper wiring: Improper wiring , such as using undersized wires,loose connections, or incorrect wires types, can cause over current.

Effect of over current in Electrical system

Damage to electrical equipment:  Overvoltage can damage electrical equipment such as transformers,motors by causing insulation breakdown,overheating,and other types of damage.

Fire hazard: Over current can create a fire hazard by generating excessive heat that can ignite surrounding materials.This can be especially dangerous in environments where flammable materials are present.

Safety hazards:  Overvoltage can pose a safety hazard to people working with or near electrical equipment,as it can cause electrical shock or other injuries.

Power outages:  Over voltage can cause power outages by tripping circuit breakers, blowing fuses or causing other types of accidents.

Solution to over current in an electrical circuit

 Install protective devices:  Installing protective devices, such as fuses, circuit breakers, can help limit the flow of current in the event of an overcurrent situation. These devices are designed to disconnect the power supply if the current exceeds a specified limit, protecting the electrical equipment and preventing fire hazards.

Avoid overloading the circuit:  Overloading a circuit by connecting too many devices or using equipment with higher power requirements than the circuit can handle can cause overcurrent.Ensure that the circuit is not overloaded can help prevent overcurrent situations. 

Properly maintain electrical equipment:  Regular maintenance of electrical equipment, such as motors, transformers, and other components, can help prevent overcurrent situations. Cleaning and inspecting equipment can identify issues that could lead to overcurrent, such as loose connections or worn components.

Use appropriate sized wires and cables:  Ensuring that the wires and cables used in the electrical system are appropriately sized for the current load can help prevent overcurrent.Undersized wires can cause resistance ,leading to over heating and over current.

Implement a ground fault protection system:  A ground fault protection system can detect and disconnect the power supply if a ground fault occurs.This can help prevent overcurrent and reduce the risk of electrical shock.

Ground fault

This occurs when a fault current flows through the ground, which can lead to dangerous voltages in the system.

Causes of Ground Fault

There are several factors that can cause ground faults. They include:

• Damaged insulator: If the rubber coating of your electrical wire is damaged, the current can flow through it to the ground.

• Wet environment: Wet environment can cause electrical equipment to rust, leading to energy loss and ground fault.

• Damaged electrical equipment: If any of equipment, such as switches, outlets, or appliances, is faulty, it can lead to current leakage and ground fault.

• Poor grounding: A poor earthing system can also lead to ground faults.

Effect of ground floor in an electrical system

There are a few hazards associated with ground faults, they include:

• Electrical shock: Electrocution is the most common hazard associated with ground faults. It happens when you get in contact with the conductor.

• Severe burn: When an earth fault occurs, much heat is generated by the increase in the flow of electricity. If an unknown person comes into contact with the hot conductor,the person  may get a severe burn.