SLC in fault after powerup

[nileshsurya 0]

hi thr u all plc experts recently i came across with 2-3 SLC systems in which one typical problem was there when the SLC is cycle powered it directly goes into fault mode,it should go into run mode but it doesnt. it is then bought into run mode by switching the key what must be the probable cause for this and what is the suggested remedy, can anybody tell plz can the status bit fault override at powerup be set to solve this problem i am also desperatley looking for the probable cause of this problem waiting for reply ASAP regards NileshSURYA

[TechJunki 0]

Are you able to connect to the SLC and read the fault, or do the comms not work?? JJ

[Guest Guest]

We set the following when using a memory module in a 5/04 S:5/8 S:1/10 S:1/8

[maximotive 0]

If you have some maths functions in your program it could be an overflow causing a minor fault which is then reset when you cycle the key switch. Try putting an unconditional unlatch of the overflow trap bit S:5/0 at the end of the program.