Basic Electrical Installation Work

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