In the process of use, protection is a very important operation, it can well prevent machine failure. In the UPS power supply equipment, in addition to the fan and circuit breaker switch components for cooling, there are a large number of solid-state electronic devices. These electronic devices are in constant use. Although there is no machine wear, they are greatly affected by their surroundings. Therefore, we need to do a good job of temperature control of UPS. Uninterruptible power supply (UPS) can not only ensure the stable operation of the machine, but also prolong the service life of the machine. Therefore, it is very important to do a good job in the daily protection of UPS.