I’m having a problem with a TSX PSY 5520M Power Supply, they stop working and I am trying to find some information that causes this problem. I have a PSX 57 453M CPU with 7 communicating racks, the Power supplies are 24V (TSXPSY5520M, I have 7 Power supplies) and after 3, 4 hours working one stop working, the green "OK" light disappears, and the Rack stay without power, sometimes after a switch off /switch on it works for a short time, and them blackout. The 400V volts power supply that feeds our Machine, is made by generators, them we have a 400/230 transformer and after another 230/24V. When I called Schneider they said that I could have harmonics created by the generators that can causing my problem, but I sent this power supplies to repair, and the the person who repaired them said to me that probably could be a high tension pick on the input line of this Power Supplies (24V line). I have a very bad environment on jobsite, dust and humidity, and this machine was stopped for 4 years long, and we started it again, but each day that we start the PLC one Power supply “burned”. If someone can give me a tip, I will appreciate that. Thanks.

For 230 to 24 you should have a filtered power supply, at least a rectifier + filter system and not only a transformer.
If the size of your generators are not adequate to the machines that you are running, including the starting phase, you may have over-voltage problems due to the generator governor that tries to compensate the small size of the generator.
And, of course, if you have been stopped for 4 years in a bad environment, you will have to verify all your installation, probably you will have problems like corrosion and bad contacts. And when you finish with the Power Supplies other problems will appear.