periodic Bad Values about node-red-contrib-s7 HOT 6 CLOSED

We are using the 1.4.1 version.. Is there any way to update it Offline?

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Bad values can happen in a different number of cases. It may happen when you have intermittent connection to your PLC, or when you have wrong addresses in your variable list, for example. Unfortunately we can't get the root cause out of the library we use.

You can update perform an offline upgrade of the package by manually downloading it from here or from npm, and manually replacing the package folder in your installation. The step-by-step instructions however would depend on your current setup (npm version, installation path and method, etc.)

from node-red-contrib-s7.

It seems that the "Bad values" error is somewhat corellated to timing/high CPU usage too. To explain better: I start getting "Bad values" errors periodically and with a high degree of repeatability when the core that runs the node-red process goes to 100% utilization and stays there for some time (which is quite often if you use Node-red on smaller / embedded devices ).

I would understand getting an occasional timeout error in such situations, but in fact I get numerous "Bad values" errors.

from node-red-contrib-s7.

Indeed. There are timeouts that can be triggered if the CPU goes 100% or if you have unstable network connection. That's also why you can configure a timeout on the node's configuration. You can try increasing it a bit and check if it gets better.

Note that "Bad values" here does not necessarily means that corrupted data is coming over the wire, it may just mean that the application does not have "good values" to deliver in that situation. System overload (my it be CPU, network, I/O, etc.) can cause this sort of issue in any protocol or protocol implementation that has time-based constrictions, as it's the case here.

Maybe your hardware is undersized for your application. We have this reading hundred of variables (~800) every 500 ms on our embedded hardware, including displaying them on a web dashboard without much performance impact. We have there a configured timeout of 5000 ms, but mainly because of network issues there.

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I'm closing this issue for now. Please let us know if the issue persists with the latest version

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