Charging problem of shante k5Pro

Reward score: 7-16 days and 4 hours before the problem ends

I just bought a backup UPS power supply of Suntech K5Pro, and the power grid in my home has not been modified, so the voltage is very unstable, so I bought a voltage regulator, but I feel that there is a problem, so I can't charge it (the yellow light is off, and I can't see any noise when I turn it off).

It's better to use the original one.

The voltage is unstable, maybe it's a problem of low electricity.

It can't be used if it is tampered with!

this is a problem!