The invention relates to UPS equipment. The UPS equipment comprises at least one power supply, at least one UPS device and a bus; the power supply receives commercial power voltage, and performs voltage conversion of the commercial power voltage so as to generate power supply voltage; the UPS device generates backup voltage; the bus outputs one of the power supply voltage and the backup voltage to a load, wherein the UPS device judges whether the power supply voltage is abnormal or not according to the level of the power supply voltage; if the power supply voltage is abnormal, the UPS device increases the level of the backup voltage to the power supply voltage, which is greater than the power supply voltage when the power supply voltage is abnormal, and outputs backup current to the load through the bus; furthermore, the UPS device gradually decreases the level of the backup voltage, and detects whether the level of the backup current is less than a pre-set current value or not, so that whether the power supply voltage is still abnormal or not is judged; the UPS device determines whether the backup current is supplied or not directly and actively; the fact that the power supply condition is known according to an external state signal from the power supply or the load is unnecessary; and the wiring and communication complexity can be lightened.