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Array A INT[32] Array Index B INT Destination C INT I am trying to move an Array (A) Element (A[2]) using a symbol (B) in ladder into a destination symbol (C) C = A [ B ] Result: ERROR: Array Index of Operand 1 out of range at rung 1 ( 6, 0 ). The documentation suggests that it is possible, but I am unsure if there is something I am doing incorrectly. Note* Fixed indexing works with no errors Is there another method to accomplish this? PLC : CJ2M CPU31 CX- Programmer: Verion 9.74 Update 1: If I go online to the PLC It does look like the array look up is working. Is the issue with the mov block? Update 2: I changed the memory locations which has caused a different error to appear. This error is clearer but does not explain the manual excerpt I posted further up ERROR: Only the constant can be specified for the index of the array. at rung 5 ( 6, 0 ). Update 3: Solution 1 I managed to hack together a proof of concept using pointers and indirect offsets Update 4: Solution 2 For some strange reason things work as expected inside of the function blocks so I made one where the array is In-Out and with an input and output respectively. Note* External reference to pointers inside of the function block produced an error. Function block Logic Update 5: Solution 3 Now I feel like I am going crazy, I tried just the original code again and it works... I have no idea why and if it was not for all the documentation I would be lost as to why it works now... Update 6: Conclusion It seems to have array indexing work the array index must exist in the D Memory Block. The reason it did not work above is because I somehow had a MOVR block when I tested after moving all the variables to the D Memory Block. I hope this journey helps someone else :)