Troubleshooting the UPS

Hi all

The output voltage of my UPS is approx 300 volts. I have also checked the transistors, they are working properly. When the battery is charging , through main supply, the output voltage is upto the normal value that is 220 volts, but as soon as the main supply fails and the UPS starts , the output voltage becomes 300 volts. Every time when the UPS comes on load the FUSE is also blowing.
Can anyone pls tell me what is the PROBLEM.

regards

Hi,


Without seeing just a guess, there may be a break in the voltage feedback path. That would mean the output would jump up very high.
To verify this might be so, you can try to vary the input voltage down to say 11v instead of 12v and see if the output drops by around 10 percent.

Hi guys. Thanks for the good work. Please help me out with this problem. I would like to power a load 960W for 5hours and 480W for 6 hours. I should give 20% (of total power demand) for allowances due to losses. The battery can be discharged to 50% and inverter efficiency is 80%.I would like to use 12V, 200Ah batteries. I am told by an expert that I need 8 batteries. Is this true. And if so, please help me calculate. Please contact: <mailmekyle@gmail.com> Thank you.