Hello to everyone
First of all sorry for my bad english.I have many smps by astec and the model is LPT43(IN=220V AC,OUT=5VDC/12VDC) ,and the problem appears when the main switch goes on and off too many times,or if the main power goes off line by a lightning,or by voltage abnormalities.Then the smps goes off and i don't have 5Vdc or 12Vdc.I open all of them and i did not found a burned fuse or short circuit.I have tested the electrolytic capacitors with oscilloscope and with a digital capacitor meter and the capacitors look's ok!
any kind of help please?
thank you everyone in advance

 

SMPS dont like being turned ON/OFF rapidly, something is going to short or go O/C. If you want help a clear picture of the powersupply would help as we have no idea what we are dealing with!