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1. When installing an electrical fire monitoring system, it is necessary to identify the number of circuits monitored by the electrical fire detectors, and to properly connect the residual current transformers and temperature sensors corresponding to each circuit. 2. The number of electrical fire detectors per circuit shall not exceed 63. 3. When making connections, the wires should be connected correctly according to the connection markings indicated on the electrical fire monitoring detector; reverse wiring is not allowed. In particular, for the communication cables, all electrical fire detectors are connected together; the bus is led to the control center and connected to the electrical fire monitoring equipment. It is necessary to distinguish between cable A and cable B: the A cable of each electrical fire detector is connected to the A cable of the next detector, while the B cable is connected to the B cable of the next detector. 4. When installing the residual current transformer, it is essential to strictly distinguish between the N wire and the PE wire. The N wire of the 3P four-wire or 4P four-wire type should pass through the residual current transformer of the electrical fire monitoring system. The N wire of the residual current transformer in the electrical fire alarm system shall not be used as a PE wire, nor shall it be grounded repeatedly or connected to exposed and accessible conductors of equipment. The PE wire shall not be connected to the residual current protection device. 5. The residual current transformer should be placed at the outlet end at the bottom of the molded case circuit breaker; when installation is difficult, an open-type residual current transformer can be considered, or it can also be installed at the inlet end of the molded case circuit breaker. 6. The residual current transformers of the electrical fire monitoring system are installed within the distribution cabinet. Special attention must be paid to construction safety: work should be carried out with the power turned off, and care must be taken to separate the wiring for high-voltage and low-voltage circuits. It is essential to prevent incorrect wiring or connections that could allow high-voltage currents to enter the circuitry of the electrical fire monitoring system, thereby destroying the entire system. 7. In renovation projects, electrical fire monitoring detectors should generally be installed at the outlet side at the bottom of the molded case circuit breaker; when installation is inconvenient, they can also be installed at the inlet side of the molded case circuit breaker. 8. In accordance with the requirements of GB13955 standards 5.7.3 and 5.7.5, an appropriate leakage current alarm threshold should be set. Generally, the alarm setting value should be at least twice the leakage current level during normal operation of the circuits and equipment, but it must not exceed 999 mA. The temperature alarm value should be set between 40 and 140 degrees, but it must be below the cable’s heat resistance limit. 9. Before powering on the electrical fire monitoring detectors and electrical fire monitoring equipment, it is necessary to check that all connection wires have no ground faults or short circuits. 10. The installation distance between the electrical fire monitoring detector and the residual current sensor or temperature sensor shall not exceed 10 meters.