Question UPS with weak batteries smells like burnt

[aor999]

When I entered my room today, all of it have a smell of burnt. After several hours, I found the cause of the smell is my Advice AIN1200-3, 1200VA, two batteries UPS which have weak batteries.
Here is a picture of my UPS:

What can cause the UPS to smell like burnt crisp?

 

[Lutfij]

What can cause the UPS to smell like burnt crisp?
The UPS's internal were fried. You need to disconnect it from your system and have a certified electrician open it up and inspect it for any options for salvaging the UPS in question, i.e, replacing the battery.

 

[aor999]

I will bring it to the computer lab of my computer technician at Thursday, to see what happened. He know do open the UPS and to replace the batteries inside it.

 

[geofelt]

I would not fool with that unit.
Replace it. If the batteries were weak, you were going to need to replace the batteries anyway.