Omron cp1e power indicator turns off

The plc runs for a minute and then the power turns off while the supply voltage is OK. I was sure that it was for the power circuit problem inside the plc. As I had a spare power circuit of cp1h and I checked it had same voltages output (5vdc, 24vdc & 0), I replaced it. Now I cannot connect it with my laptop to change to run operating mode. Could anyone help me?

If you look at the LED lights on the CPU unit what is the status of the Power, Run and ERR/Alm?
When the PLC runs for a minute, are Power and Run lights are on?
Does the Power light stay on and the run light goes off or do all of the lights go off?
Is the ERR light coming on at any time?

When the PLC runs for a minute, Power, Run and RS232C LED lights are on. Then all the lights go off. ERR light never coming on at any time.
The supply voltage was always connected and it was 253 Vac from an isolation transformer. We thought that the PLC circuit may be damaged for the over voltage as the PLC range is 100 to 240 Vac. So we reduced the voltage to 230 Vac from another source.
The problem was not solved yet.

I would try connecting the PLC through a UPS. This will filter out any surges that may be present on the line and ensure clean power.
If the PLC is still failing, I would return for warranty or repair.

Regards,