Distribution box electrical components selection configuration - Database & Sql Blog Articles

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1. The main distribution box must be equipped with power isolation, circuit connection and disconnection functions, as well as protection against short circuits, overloads, and leakage. It typically includes one incoming unit and one or more outgoing units. It should feature a transparent molded case main circuit breaker with visible break points, and a visible shunt trip mechanism that can automatically disconnect when the auxiliary power fails. Each output loop should have a three-point terminal block for easy connection and maintenance. 2. The total number of distribution circuits in the main distribution box (distribution cabinet) should range from 1 to 5 loops, depending on the application requirements. 3. The distribution electric box is composed of one incoming line unit and several outgoing units. It should be fitted with a transparent molded case circuit breaker with visible break points, along with a five-point terminal block for each outgoing circuit. This ensures clear visibility and safe operation. 4. The number of distribution circuits in the distribution electric box should be between 2 and 7, providing flexibility for different load configurations. 5. The switch box consists of an incoming line unit and an outgoing line unit. It should include a transparent molded case circuit breaker with a leakage protector and a five-point terminal block, all featuring visible break points for safety and ease of inspection. 6. The transparent molded case circuit breakers in the main distribution box, distribution electric box, and the visible break point in the switch box should be installed at the power input end, ensuring that operators can easily identify the status of the electrical system. 7. The main distribution box must be equipped with a voltmeter, a total ammeter, and a watt-hour meter. These instruments should not share the same current transformer. When installing a current transformer, the secondary circuit must have a grounding point connected to the protective neutral wire, and it is strictly prohibited to open the circuit during operation. 8. The rated leakage current of the leakage protector in the main distribution box should be greater than 30 mA, and the rated leakage operation time should be greater than 0.1 seconds. However, the product of the rated leakage current and the rated leakage operation time must not exceed 30 mA·s to ensure effective and safe protection. 9. The leakage protector in the switch box should have a rated leakage current not exceeding 30 mA and a rated leakage operation time not exceeding 0.1 seconds, providing rapid response to potential hazards. 10. It is strictly forbidden to use plug and socket connections for the power supply terminals of the distribution box and switch box. Direct wiring is required to maintain a secure and stable electrical connection. 11. Each distribution box and switch box should clearly display its name, purpose, shunt markings, and a system wiring diagram for easy identification and proper installation.