Hi all,
I am new to the forum. These days I am repairing a PJ 48V/230 AC LF inverter. It came with no output.Customer said it is a 5KW unit. Observed blown 5V regulator, switch mode FET and a diode in the main board power supply.
I managed to fix this and the 12V and 5V are now OK. But still not doing anything apart from that. Main board (LF-PSW-MAIN-BOARD Rev 1.8 has IRF 3710 (all 20 pcs and SMD resistors are good.)
I can feel the main processor MC908MR32CFUE warming up too much, oscillator not running. So I suspect this.I have got down a replacement chip with the same number.
Before going ahead,I like to study the interconnections between the main processor and other small ic s around it so that I don't fry it again.
I have read almost all the threads in Other power, Another power and elsewhere about this inverter. Cannot find any discussion about the operation of the control system.
All I am looking for is an interconnection diagram preferably with waveforms. If any of you good guys have experienced this before, please shed some light.
Where can I find a complete schematic or block diagram of this board. (Power Jack LF Control Rev 1.4 CTRL-INV 2013/08 Rev 1.2 ) This has a daughter board for the gate driver with two TLP 350