Hello everyone,
I am new with Ignition. I’ve used WinCC and PCS7 for several years.
I’ve got one question: in PCS7 you can have alarms with a timestamp accuracy of 1 ms when using digital input cards like 6ES7321-7BH01-0AB0 with the header 6ES7153-2BA10-0XB0, connected by Profibus to a S7-400.
With Rockwell ControlLogix is also possible to get this accuracy in the timestamp of digital inputs.
Is it possible with IGNITION to achieve this accuracy? Or at least to get the alarm with the timestamp of the cycle of the CPU?
I’ve read in the manual the option of timestamp source “value” when configuring an alarm, but I don’t really understand what that means.
Thanks for your help.
The accuracy or presence of a source timestamp on a value from OPC-UA depends on what device/protocol the value comes from. With the exception of DNP3, none of our drivers receive a source timestamp when polling values from the device (not for lack of support on our end, it’s just not part of the protocols). So the source/server timestamp values will be identical and represent the time at which the server received that value from the device.
Ignition won’t do this an any automated way, but it is possible with some PLC code. Basically, you have to capture the input card’s timestamp in the PLC and place it in a register available to Ignition. Or in a queue of custom event structures. In a Logix processor, you would add the CST-Localtime adjustment offset to get a 64-bit Unix-style timestamp with microsecond precision. If you want accuracy too, not just precision, the HiProm GPS module is a good (if expensive) choice. It offers GPS-sourced time via Precision Time Protocol to devices that support it (Logix Coordinated Time), and via regular NTP to everything else.
OK, so the choice would be to add associated data to the alarms, with a new register of the timestamp linked to the PLC code.
I think it is possible to do with ControlLogix as pturmel explains. With Siemens PLCs it would be more complicated but possible as well.
Thank you very much for your replies.