Circuit Protection Devices Pdf

Circuit protection devices are available in a variety of types shapes and specific current ratings.

Circuit protection devices pdf.

Up protection where the normal protection is provided by some other device such as a circuit breaker or a motor overload trip according to iec standard two classes of lv cartridge fuse are very widely used. A fuse is placed in an electrical circuit so tht when current flow exceeds the rating of the fuse it blows or blows out. But before you can size the ocpd you have to determine what load it will supply. So sizing the ocpd logically comes before sizing the conductors.

This link will be broken in the event of a fault whether that s high temperature excessive current or a short circuit in a conductor thus protecting the electrical circuit it s part of from damage. Fuses a fuse is the simplest circuit protection device. The purpose is to. Even though guidance exists in the form of the various electrical codes the wide variety of product offerings can make the proper selection of circuit protection devices a challenge.

The overcurrent protection device ocpd whether a breaker or a fuse defines the circuit. Discrimination with the higher level protection devices must be provided. The two types of circuit protection devices discussed in this chapter are fuses and circuit breakers. This is the area of the miniature circuit breaker these circuit breakers are designed to protect final distribution.

The protection devices are placed directly upstream of the loads. A weak short circuit current a few ka characterises this level. It derives its name from the latin word fusus meaning to melt fuses have been used almost from the beginning of the use of electricity. For domestic and similar installation type gg for industrial installations type gg gm or am.

Circuit protection at its simplest is the intentional addition of a weak link in an electrical circuit. Let s start with looking at the order of the calculations. The residual current operated circuit breaker with integrated overcurrent protection is a protection device that combines the functionality of rccb and mcb and is used in residential xpole series as well as industrial xeffect series applications. Protection devices for electrical circuits accomplish two main functions namely consistency as well as protection.

Circuit protection devices protect expensive systems by rapidly disconnecting power to compon ents in the event of an ab normal operating condition.