The excess circuit protection device which will not operate within four hours at 1.5 times the designed load current of the circuit which it protects. Device affording coarse excess.
Which is the example for coarse current protection?
Excess Current Prptection which is not operate within 1.5 times the designated load Current of the circuit, which is protects. Devise affording Corse Excess Current Protection includes BS 88 fuses fitted with fuse links marked to indicate a class Q2 or class R fussing factor. Hope it helps!!!
Which electrical device is the course excess current protection?
Fuses, circuit breakers, and current limiters are commonly used overcurrent protection (OCP) mechanisms to control the risks. Circuit breakers and fuses protect circuit wiring from damage caused by overcurrent.
What is fusing factor?
Fusing factor. It is the ratio of minimum fusing current and current rating of the fuse. Minimum fusing current is the minimum value of current due to which fuse melts. The current rating of fuse is the maximum value of current due to which fuse does not get melt.
What is cartridge fuse?
Cartridge fuses are a low cost electrical safety device that is used to protect electrical circuits and appliances. They are cylindrical in shape and have a contact point at each end. Cartridge fuses are typically constructed from ceramic, glass or porcelain.
What is used to prevent too much electricity from flowing through a circuit?
Summary. An electrical fuse is a device that sacrifices itself to provide over-current protection in an electrical circuit. If too much current flows, the fuse wire rises to a higher temperature and melts, thus opening the circuit, but destroying the fuse.
What reduces the flow of electricity?
An electrical insulator is a material through which charge cannot flow easily. A metal wire is usually coated with plastic or rubber. The metal wire is an electrical conductor. The rubber and plastic are electrical insulators.
Which device opposes current?
A capacitor is basically a device which stores electrical energy in the form of an electric field, while an inductor is a component which stores that energy in the form of a magnetic field.
How do you size a neutral wire?
Sizing the neutral: Sec. 220-22. You must size the neutral conductor to carry the maximum unbalanced current in the circuit (i.e. the largest load between the neutral and any one ungrounded phase conductor). You calculate the first 200A of neutral current at 100%.
How do you calculate a fusing factor?
Fusing factor is defined as the ratio of minimum fusing current and the current rating of fusing element. Fusing factor = (minimum fusing current / current rating of fusing element).