Effekta 700MH

[salaskir]

The problem concerns the Effekta UPS, model 700MH. Initially, I got the UPS with blown fuses (3x BEL FUSE MQ 15A 125V) in the battery path. Searching for the reason, I came across two burnt IGBT transistors of the inverter (Toshiba GT15Q101) and one of their drivers (Toshiba TLP250F). I replaced the fuses, transistors with (IRG4PH40UDPBF) and prophylactically both drivers with the same. The inverter is up, it gives a nice sine output from the charged batteries. There are no problems with switching between the mains and battery power.

 

One might say that it is fully functional, but the batteries are not recharged, however. In the event of a power failure, it works on batteries until they are discharged, after the appearance of the network, it no longer charges them, they remain discharged. I did not find any diagrams or even photos on the web. After the connections I got to the charging path (in my opinion), there are two transistors working there, IRFP460 and 2SK2850. Both are operational. Has anyone encountered a similar problem and will help me with some tips or a diagram?