automatic fault reset

[active]

Hi all

Is there anyway of resetting a plc fault and putting plc back into run automatically say by setting a SB in the program on startup

Thanks

[Stein Yair]

HI,

SB 24 perfors Reset and Initialize.

SB 300 performs Reset.

You can also Reset and/initialize from VisiLogic under Connection > Communication & OS, in the Functions tab.

Reset - like power up. Reinstalls any values preset in the program, such as Timers.

Initialize - reinstall any preset values, and initialize all memory operands.

[Simon]

But if the PLC has put itself into stop mode how can it then set SB24 or SB300?

I think the original question was asking can this be done without user intervention. Kind of like a self-resetting watchdog - if the PLC goes into stop mode, automatically reset it.

Possibly you would want a limit on the number of times it would self-reset, so if the fault was permanent the PLC would stay in stop mode after a certain number of reset cycles.

Note also that if the PLC is being remotely monitored, SB302 will indicate if the PLC has gone into stop mode, giving the possibility to reset the PLC via remote connection.

[active]

Thanks Simon

Thats exactly what I meant, should learn to be more descriptive, had a V570 go into fault expansion card error was able to reset via ethernet modem. Little bit concerned as some of our V570s are on remote unmanned sewerage treatment plants would like the plc to try an automatic reset even if its gone into stop mode.