Sebastian;
You can use the "Equal to 0?" function under the Comparison palette. It will generate an array of true/false values, true meaning that the corresponding value is equal to 0. Then you can "And" the array using the "And array elements" function, which is under the Boolean palette. If there is a value other than 0, the result will be "False".
I attached a vi that do the non-zero check.
Enrique
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