To fully utilize the protective effect of a fuse in a circuit, the position of the fuse in the circuit should be considered when designing the circuit.
The fuse can be blown in a timely manner to protect the circuit and switch;
And the fuse cannot be blown in a timely manner, unable to protect the front-end circuit and switch. If a short circuit occurs at B, the fuse can only be blown in a timely manner, which can protect the circuit;
As shown in the circuit diagram, when a short circuit occurs at point A, the switch will still burn out, while the fuse will not blow, meaning that the fuse in this circuit cannot protect the circuit and electrical components. So the circuit diagram is the most reasonable one for designing the position of the fuse in the circuit.
Note: For the case where relays and fuses are integrated in the same electrical box, the fuse connection is not closely related (as the possibility of a short circuit occurring within the same electrical box is not high), otherwise the most reasonable connection is as shown in the diagram.
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