Sometimes i have problems with the communication to a Siemens PLC. Now i wanted to catch this problem so i can send a message or email when this happens. I set it up as you can see in the picture below:
But as you can see there is no output from the catch node when the error is there. So i assuming the S7 node doesn't support the catch node.
But is there another way to get the error?
The catch node can only work when the code creating the error includes the error object in the output. So that is, as you say, down to the author of the node to fix.
Not many options really:
Get the author to fix the code
Use a lower-level node.js module instead with a function node so that you can trap errors for yourself
Find an alternative way to get information from the device.
(or) edit the .js file - find where the error is sent - you will likely see node.error(errMsg) and change it to include the incoming msg e.g. node.error(errMsg, msg);