Created Date: July 27,2019

Created by: Fenix

I am developing a control system for remote locations using a BRX PLC and C-More EA9 HMI. I am looking for some examples of handling potential errors programmatically. I realize "handling potential errors " is a pretty broad spectrum but any examples will help. One thing I am thinking of is if the PLC looses communication with the HMI. The C-More has the "Good Communications Toggle " but what about on the PLC end?

Created Date: July 28,2019

Created by: Garry

https://accautomation.ca/c-more-ea9-hmi-series-panel-to-plc-and-plc-to-panel-settings/

https://www.youtube.com/watch?v=b_KsLBDrtOU

The panel to plc and plc to panel selection will help with all of your errors on both ends. See the above post for an example.

Regards,

Garry

Created Date: July 28,2019

Created by: Fenix

Thank you for the information Gary though not quite what I need. Using communications with the HMI as an example, if the PLC and HMI loose communication with each other the PLC program needs to be aware and turn off certain processes until communications are restored. It is not just a matter of alerting a user but rather handling the errors programmatically at runtime (as much as possible).

Created Date: July 29,2019

Created by: Garry

Hi Fenix,

What I would do then is create an invisible pushbutton on the screen. Set it to a momentary off object type. This way the HMI is always sending an 'on ' condition to the bit in the PLC.

https://accautomation.ca/c-more-ea9-hmi-series-panel-object-list-buttons/

In the PLC use the leading edge of the one-second pulse bit to see if the bit is on. This will indicate good communication. Use the trailing edge of the pulse bit to reset the bit. This will give the HMI 500 milliseconds to set the bit again.

A communication error with the HMI will be present if the leading edge of the one-second pulse bit and the bit is off.

Hope this helps you out.

Regards,

Garry