PLCLogo : Irregular 0-values from analog items

  • Platform information:
    • Java Runtime Environment: V21, according openHAB installation
    • openHAB version: 5.0.1
    • Code: rulesDSL
    • Logo BA8
    • openHAB gets operated in a docker container
  • Issue of the topic: Analog values get stated as 0 irregular

Reading analog values from Logo BA8 devices does give me irregular and at different frequencies

the Value 0 even typically the Value shall be different from 0.

First I was under the impression that perhaps the analog input for logo BA8 may cause the issue, now I have the same issue with an simple circuit and an explanation by potential analog input issues of the Logo became a more and more weak argument. I programmed a Trap to the LOGO-program that shall count if a particular analog input has a 0-Value to get an idea it´s related to Logo BA8 or related to the PLCLogo Bindung. Result does tell a clear message: There are no 0-Values at the analog input indicated by the trap but 0-Values are stated in openHAB.

In addition tracing analog items with the Logo-IDE does not show any 0-Value while trials.

The 0-Values are just exceptional in a one time poll interval.

The use of a filter that collect 256 cycles a Value and gives back the mean does also get shown as a 0-Value sometimes. Next indicator that there´s something on the software, not the hardware side.

Example configuration in openHAB:

Thing:

Bridge plclogo:device:Logo2 [ address="192.168.xxx.yyy", family="0BA8", localTSAP="0x3000", remoteTSAP="0x2700", refresh=200 ]

    {

Thing analog AI_L2        [ kind="AI"]

Thing analog AQ_L2        [ kind="AQ"]

Thing analog AM_L2        [ kind="AM"]

Thing analog NAI_L2       [ kind="NAI"]



    }

Item:

Number      NUM_AI_L3_AI2 "L3 AI2  [%.0f cV]"    { channel="plclogo:analog:Logo3_lf:AI_L3:AI2" } 

As in general analog values get stated correct I assume the setup of the binding is correct.

What may be a root cause that analog values get stated as 0 even in the LOGO BA8 a significant different value is shown ? How does Moka7 library act here ?

The mentioned issue does happen for all analog items: AI input, AM analog Marker, NAI network input.

Being a bit helpless at present bit this occasionally issue.

As this values get persisted in influxDB2 a code solution in rulesDSL simply to block any 0-value code is not an option here.

Any comments or a need of further information pls. let me know.

Frank