To measure the 5 V voltage of the health pot, it is necessary to put the multimeter in the AC voltage range and put its two probes on the phase line and the zero line of the current respectively, so that the voltage of the electric kettle can be measured.

The working voltage of the single chip microcomputer which plays a controlling role in the incubator is generated and provided by the switching power supply. If the output voltage of switching power supply is not enough, the single chip microcomputer will not work normally. When this happens, it is necessary to test the sampling amplifier and feedback circuit of single chip microcomputer, and to test related components including rectifier diode filter capacitor optocoupler and tl43 1 to check the faults one by one.