6/14/2017 1:18 PM | |
Joined: 2/24/2016 Last visit: 9/6/2024 Posts: 32 Rating: (7) |
Hi I'm reading data from an S7-1200 using node-red (node-red-contrib-s7, v1.1.2). I can read and manipulate the data perfectly. If I unplug the PLC, I get the following message in the debug window as expected. 6/14/2017, 10:29:07 PMnode: MUX1-PLCmsg : string[69] "Error connecting to PLC: Error: connect EHOSTUNREACH 192.168.0.25:102" I would like to inform the user that the PLC connection is healthy (or not). However, when I intentionally disconnect the PLC, the flow seems to completely stop. The output from an error catch node is empty. The output from a debug node wired to the S7 input node is also empty. On Simatic HMIs I display a 1Hz flashing indicator to indicate connection health. If the connection is disrupted, this stops flashing and eventually goes to a null value. I could implement the same here however, node-red seems to retain the last read value which could be 1 or 0. Therefore this is an unreliable way of displaying the connection status since the indicator could be stuck on OK which looks like the connection is good to the operator. Is there a way of reading the status of the connection to the PLC? I have had a look at an alternative package (s7comm v1.0.2) but this seems to be unfinished with missing items from various drop down menus in the configuration pages for the PLC connection. The input nodes do however provide some information on the connection status and the flow keeps running if the connection is down. Any help would be great Thanks! |
Last edited by: j.w.eichler at: 6/14/2017 1:19:03 PMLast edited by: j.w.eichler at: 6/14/2017 1:25:26 PMLast edited by: j.w.eichler at: 6/14/2017 1:27:27 PM |
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6/19/2017 8:06 AM | |
Posts: 215 Rating: (6) |
Here, in the first two posts, are some instructions on how to test a connection to a plc. |
This contribution was helpful to2 thankful Users |
6/19/2017 9:05 AM | |
Joined: 2/24/2016 Last visit: 9/6/2024 Posts: 32 Rating: (7) |
Thanks! That's really useful. I will test it later. |
9/22/2017 7:43 AM | |
Joined: 6/19/2017 Last visit: 9/6/2024 Posts: 8175 Rating: (172) |
New question published by Magica is split to a separate thread with the subject Cannot monitor all the variables through Node-red. Best regards |
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