Repeat restart of the briquette machine is usually caused by the low power supply, which can not drive the briquette machine to work normally. First, the power supply voltage of the briquette machine is detected by AVO meter, and it'd better detect under the condition that the briquette machine is loaded so that to judge whether there is any power supply problem. In addition, when the briquette machine works normally, the power voltage would better be no less than the standard voltage. When the standard voltage is at the value of 24VAC, the voltage fluctuation should be no more than 25%.