An earth wire only " works " under fault conditions in an electrical circuit . The earth or circuit protective conductor protects any conductive part of the system which under normal conditions should not be live , for example the metal casing of a washing machine . The earth , during a short circuit , will complete the circuit and the system will fuse/trip/disconnect if protected suitably .
Earth wire is meant to protect the user in case there is earth fault in the device or circuit. Only earth wire alone is not sufficient. It needs to be provided with suitable circuit breaker that breaks the circuit automatically.
Yes, a loose neutral wire can effect the operation of Earth Leakage Circuit Breaker.
1. protection against fire hazard from a short-circuit. A short-circuit can be caused by a loose wire, faulty insulation, or faulty wiring. A short-circuit will cause the wires to heat up rapidly, presenting a fire hazard. 2. protection against circuit overloading. Too much current in a wire caused by overloading (plugging in too many high-power appliances, for example) can cause overheating, presenting a fire hazard. Most circuit breakers have a "slow-blow" mode that breaks the circuit if overload continues for too long. 3. on grounded appliances (which have the third prong on the plug), the ground is connected to all exposed conductive material on the appliance. In the event that a loose wire contacts the exposed metal, a short-circuit will occur, and the power will be cut. This protects against accidental electrocution. Circuit breakers do not protect against fire hazards from inferior gauge of wire, glow-faults, or arc-faults. Most do not protect against electrocution hazards from ground-faults (although some do).
I suspect that it is because a coiled wire becomes an electro-magnet which disipates and uses energy, and is therefore not recognized as a short.
why does have to short-circuit secondary wire of current transformer ?
A fuse is typically connected to the live wire in a circuit. This is done to protect the circuit from an overload or short circuit, as the fuse will blow or trip and cut off the current flow if there is an issue.
The wire that connects the power source to the rest of the circuit should contain the fuse. This is typically the wire that leads directly from the positive terminal of the battery or power source. Placing the fuse in this wire helps protect the circuit in case of a short circuit or overload.
Earth wire is meant to protect the user in case there is earth fault in the device or circuit. Only earth wire alone is not sufficient. It needs to be provided with suitable circuit breaker that breaks the circuit automatically.
A "hot" positive wire has made contact with ground = short circuit.
Short in the circuit or the circuit was overloaded.
A ground (earth) wire is needed in not just a light circuit but in all circuits that are now installed.
The circuit stops working because of the short circuit
A short circuit occurs when a low-resistance path is created between two points in a circuit, causing excessive current flow. This can happen due to a wire touching another wire, a conductor coming into contact with metal objects, or a component failure. When a short circuit occurs, it can potentially lead to overheating, damage to components, and even fire.
They protect the downstream components from spikes in the eletrical system.CommentFuses and circuit breakers do not protect against 'spikes', which are near-instantaneous voltage increases. Fuses and circuit breakers are overcurrent protection devices, which protect appliances against excessive current due to overloads or short circuits. CommentFuses and circuit breakers are used to protect the wire feeder that supplies the load. A load could be connected to a circuit that would cause an increase of amperage above what the wire is rated for. If this condition happens the fuse or circuit breaker will open the load from the supply service.
An electrical short circuit is when two bare wires touch each other. Or when one wire's insulation wears too thin and the bared wire touches the metal chassis of the device and is led to earth.
In the visible spectrum or the infrared? Either way, if your earth wire is glowing you have a problem. Your earth wire is not intended as a current carrying wire. If the wire is loaded to the point that it glows then your circuit/breaker is not wired correctly and the earth wire is being used as an unintended path and is a hazard. Earth wires are not sized properly to carry current.
A short circuit is repaired by first finding out where the short circuit occurred. On major faults usually the wires are removed and new wires are installed. On minor faults, the wire that shorted is separated from the offending wire or separated from the grounding medium. To put the conductor back into service the wire's insulation has to be brought back to the level of what the wire was when it was new. Once that is done the circuit can be re-energized.