Alarm in Citect when communication error?

[callelundin 0]

Hey! I whant to trigger a digitalalarm on citect when if commuication to PLC is lost. is there a function for this? I can read a bit (allways 1) on the PLC and put it in a digital alarm, but i vould prefer to use something else, do anybody have an idea? how do you boys/girls do? best regards cAllle

[Gambit 324]

Use the cicode IODeviceInfo(IODevice, Type). This can return the status of your I/O Device. which you can use to set/rst a bit

[tragically1969 0]

Gambit has the answer, just be careful though as Citect will retry the comms every 30 seconds or so, this means your alarm list can fill up pretty quickly with comms alarms if you dont manage it well.

[lostcontrol 23]

Other standard practice for this type of thing, is to have an incrementing counter in the PLC, and also in the SCADA. When the PLC Counter value changes, then the SCADA value is reset, it the SCADA value is greater than a certain value, then the alarm is set. This makes it totally independant of any driver typem issues that may trick into fooling you that comms are actually ok. If comms are lost, does Citect set the bit to 0?