E300 OL relay generating data while DCed

>delete all instances where I'm writing in this datablock

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Ken Roach said:

What exact sub-elements of the Input tag "get written" ?


I've only noticed that one that Im using like ready / average current and some other



Do the values actually *change* and update ?


Bool values go from 0 to 1, average current goes from 0 to some value(could be the last value before disconnecting)


It is normal for the Input data to remain the last state from before the communications loss. A-B devices typically allow you to monitor the connection to be sure the data is valid, rather than implying there's something wrong by setting all the values to zero or another out-of-range value.


Ok, I was checking connection state by using gsv block and if the communication isnt good, I would just copy empty block to this one, and somehow, values kept changing. Even where there is a no chance of communication(only ethernet cable pulled out)



That's an Input tag, which will be automatically updated by the I/O connection. You should not have any logic or HMI that "writes" to any element of that tag.


I never had this problem or similar problems just to set these values to zero if i lose communication with that certain device, now im using a buffer and it solved the problem but still... i would like to know why it happens.

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>if the communication isnt good, I would just copy empty block to this one, and somehow, values kept changing.

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Ken Roach said:

I think that the values *appear* to be changing because your logic is competing with the I/O connection automatic data transfer.

Use the value of the GSV EntryStatus, divided by 4096, to determine if the connection is running. 4= Running, anything else is a broken or re-establishing connection.

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