I got this all in one charger / inverter / UPS http://carspa.en.made-in-china.com/p...600W-10A-.html with blown IRF3205s and two 40A fuses on the output. It supposedly happened when "electricians" (more like stupid idiots) played the grid like piano (you know how the idiots use to turn power grid on and off ten times in a minute?). It was powering some systems regarding to coil furnace.
I've replaced all the eight transistors and both fuses, there was also blown cap, replaced too, also with a small 22uF cap going to hell (7,4 ohm ESR). It still behaves the same way: when I turn on the charger, it works OK. When I turn on the inverter, it starts eating tremendous power (10 A) and than cycles: it beeps, starts eating 24 A, than it drops to 10 A again, and that goes over.
It basically has one small PSU for charging and than additional high-power circuitry/inverter consisting of two. Only one of them heats so much. Any quick thoughts? If not, I'll tell the owner its PoS and to buy new 600VA UPS from my colleague, designed especially to power circulating pumps and this stuff.
I've replaced all the eight transistors and both fuses, there was also blown cap, replaced too, also with a small 22uF cap going to hell (7,4 ohm ESR). It still behaves the same way: when I turn on the charger, it works OK. When I turn on the inverter, it starts eating tremendous power (10 A) and than cycles: it beeps, starts eating 24 A, than it drops to 10 A again, and that goes over.
It basically has one small PSU for charging and than additional high-power circuitry/inverter consisting of two. Only one of them heats so much. Any quick thoughts? If not, I'll tell the owner its PoS and to buy new 600VA UPS from my colleague, designed especially to power circulating pumps and this stuff.
Attached Files
Half of the computer problems is caused by bad contacts 
