SLC 504 retain i/o state after power lost

new to PLc by the way but here is my question. whenever i loses power to my plc the i/o state resets to 0 on all the sequence steps in the programming. is there something on the plc controller i have to enable. not sure thanks for any help. keep in mind i am working on a existing plc login.

thanks

sonic99

what kind of plc? There is probably somethings in the plc settings that can be set up to retain previous state on power outage. You may also need a batery backup to retain states.

you can use remote I/O with output state retain function

Do you mean your I/O or do you mean your internal memory B3, N7 etc ? I would expect your I/O to reset to zero if you lost power because after all the Inputs are driven by power If you mean your internal memory then I seem to remember something about B3 file sbeing non-retentive and N7 files being retentive , hopefully someone with more knowledge of AB SLC's will chime in.

I think he is stating that the bits in the PLC program are not retentive. This is more a program issue than a hardware setup issue. This is one thing I used to love about the old S5 PLCs. The 115u had a retentive , non-retentive toggle switch, that would allow the program to save all the flags after a power down/ power up sequence due to a power failure.