Table of Contents
What is the cause of voltage fluctuation?
One of the most common causes of voltage fluctuation is an obstruction in the transmission lines. Obstructions are mostly caused by natural factors such as thunder, lightning, fallen trees and heavy rains. This accidental dip in the voltage level leads to extreme power surges or brownouts.
What are the effects of earth leakage?
Consequences Earth Leakage current beyond 30mA can be lethal leading to death. 30mA sensitivity is required for protection in domestic applications where the person may come in direct contact with electric equipment in locations such as labs, schools, workshops etc.
How can current leakage be prevented?
The best ways to prevent leakage current are to always use shielded cables on motor installations and to make sure that these cables are grounded at both ends. Also, check cables and insulation for damage and replace ones that are broken or damaged.
Does an earth leakage use electricity?
Earth leakage is electric current that finds its way to earth via an unintended path. Whatever the source of earth leakage, it must be prevented from causing electric shocks. This is usually done by using either RCDs (residual current devices) or RCBOs (residual current circuit breakers with overcurrent protection).
Why is it important to understand the concept of earth leakage?
It is important to understand this concept as it can lead to a situation where a short between earth and neutral in one circuit may not be sufficient to trigger the earth leakage trip (residual current below 30mA). This is because the voltage difference is too small to generate sufficient current flow to trip the RCD .
Does the live wire cause residual leakage faults?
Sometimes. Most of the time the “Live” wire is responsible for a residual leakage fault. This is predominantly due to the higher voltage differential and so the greater potential to drive a current where it is not supposed to go.
What are the effects of voltage fluctuations?
2. Effects of voltage fluctuations. Voltage fluctuations can be described as repetitive or random variations of the voltage envelope due to sudden changes in the real and reactive power drawn by a load. The characteristics of voltage fluctuations depend on the load type and size and the power system capacity.
What causes voltage to increase between neutral and Earth?
In complex electrical installations, or some where the wiring may be old, have poor connections or otherwise has excessive impedance, the voltage between neutral and earth can increase, particularly at the furthest points from the distribution board and particularly where high currents are involved.