Please see §3 of our Terms and Conditions which applies for Germany and Europe.
§3 is extended by our 30 Days Money Back Gurarantee worldwide. If the customer is not satisfied with one of our products we will give refund of the selling price after the customer sent the products back to us. If the customer asks for refund it has to cover the shipping costs and the product must be full functional and “normal-used” condition.
The warranty explicitly excludes malfunction caused by inappropriate conditions e.g. voltage, humidity or temperature.
An example for this is when an IO Module is connected to signals which are outside of the specified range.
Especially output modules which have defect driver elements may indicate overload. These cases are not by nature covered by the warranty. But even then it is often possible to repair or replace defect components.