The resistance wire of Xiaogang electric blanket is broken. Dad connected the resistance wire and continued to use it. During use, it was found that the connector was burnt. Please tell me the cause o

The resistance wire of Xiaogang electric blanket is broken. Dad connected the resistance wire and continued to use it. During use, it was found that the connector was burnt. Please tell me the cause of the burning. This formula Q=U? R×t is the heat reflecting the whole resistance.

And the formula Q=I? Rt reflects the heat of any resistance in a series circuit. When the resistance wire is not broken, there is only one resistance in the circuit You can use this formula to calculate. When the heating wire is broken, the circuit becomes a series circuit composed of three resistors (two heating wires become two resistors, and the connection point is a contact resistor). If the joint of the heating wire is in good contact, there is no contact resistance, and the heat there is consistent with all resistance wires. If contact resistance appears at the joint due to overheating after a period of use, the contact resistance is much greater than that of the other two heating wires. In a series circuit, the current through each resistor is equal. The larger the resistance, the power consumed on this resistance P=I? The greater the R, the heat accumulated there Q=I? Rt rice is naturally very big, and it will definitely burn out the electric blanket.

I don't know if you understand.