Channel %1 block %2 motion synchronous action: system variable access not possible


%1 = Channel number

%2 = Block number


When using system variables, it is assumed that a read/write operation can access the required data successfully. In accesses to encoder actual values or digital I/Os, the result depends on the availability of the corresponding hardware components. If an access within synchronized actions does not return a valid value, alarm 20144 is output. Outside synchronized actions, such a read/write access causes block execution to be interrupted until the result is available. Block execution is subsequently continued.


- NC Start disable in this channel.


-    Interface signals are set.

-    Alarm display.

-    NC Stop on alarm.

Before reading/writing system variables, ensure that it is possible to access the required hardware components.

Program Continuation:

Clear alarm with the RESET key. Restart part program

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