Thanks for the responses - the problem was that I use the RTC-Axpert 5KVA inverter as a standalone inverter and then the setting 28 has to be on SIG - it was on PAL. Everything working just fine now. BTW, the 03 setting is on APL.
Good day, I'm sure other folks must have encountered the problem that the inverter does not accept AC from a generator - can any one please help? Regards