Digital input always ON/OFF

We use PLC CPU414-2DP, now I meet this fault: a lot of digital input with 24vdc always change status  1-0-1-0..... ( true status of them is 1), I changed supply power, check outside connection but do not find the reason for it, I do not know which lead to this status, please help me if you have any answer.

Thank for your answers.

Hello,

Perhaps you can give some information about the Digital input Cards you are using?

Best regards,

Wizard

Hi,

Please give us details on the signal you are connecting to these DI channels. And double check wiring from the sensor to DI module.

Hi Ayman Elotaify

I check in buffer diagnostics of CPU, and it report like following picture.

I hope you can help me.

Thank for your answer.