Basic Electrical Installation Work

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FIGURE 12. The toggle switch can also used disconnect the circuit for maintenance isolation test the MCB for satisfactory operation.Overcurrent, short circuit and earth fault protection 243 electromagnetic devices normal operation but under overcurrent condi- tions they activate and trip the MCB. ADVANTAGES MCBs ● They have factory set operating characteristics. ● faulty circuit may quickly identified. This latches the various mechanisms within the MCB and ‘makes’ the switch contact. ● The circuit provided with discrimination. . ● Tripping characteristics and therefore circuit protection set the installer. DISADVANTAGES MCBs ● They are relatively expensive but look the advantages see why they are popular these days. The circuit can restored when the fault removed pressing the ON toggle. CHARACTERISTICS MCBs MCB Type 60898 will trip instantly between three and five times its rated current and also suitable for domestic and commercial installations. ● The supply may safely restored unskilled operator. ● The circuit protection difficult interfere with.3 MCBs Breaker, fits Wylex Standard consumer unit (Courtesy Wylex). ● faulty circuit may easily and quickly restored. ● They contain mechanical moving parts and therefore require regular testing ensure satisfactory operation under fault conditions