In general there are two circumstances that will cause the power supply to shut down. The first one is the activation of the over-load-protection (OLP). To deal with this situation, we suggest increasing the rating of the output power or modifying the OLP point. The second one is the activation of over-temperature protection (OTP) when the internal temperature reaches the pre-set value. All of these conditions will let the S.P.S. enter protection mode and shut down. After these conditions are removed, the S.P.S. will be back to normal.

Generally, there are about two reasons for the shutdown of the power supply in use. First, overload protection may be caused by instantaneous overload of load. It is suggested to increase the output power of the power supply or modify the overload design. The second is that the temperature rise is too high, resulting in over-temperature protection. All of the above situations will cause the power supply to crash due to entering the protection state, and the power supply can return to normal after the condition is relieved.

Power Factor Correction or PFC is to improve the ratio of apparent power to real power. The power factor is around 0.4~0.6 in non-PFC models. In models with PFC circuit, the power factor can reach above 0.95. The calculation formulas are as follows: Apparent Power=Input Voltage x Input Current (VA), Real Power= Input Voltage x Input Current x Power Factor (W).