EP0568837

The invention relates to a device for identifying a substance located in a solid or fluid container by means of a code carrier, the code signal of which is detected by an evaluating device for deriving an enable/inhibit signal for a filling or emptying process of the solid or fluid container. To obtain an inexpensive and reliable implementation of such a device, the code carrier is constructed as transponder which can be read or loaded via an inductive coupling device integrated in the filling hose. As an alternative, the transponder identifying the tank content can also be replaced by a computer controlled device emulating the behaviour of the transponder which, apart from more flexible possibilities of use, also provides for a more extensive bidirectional data transfer. Another embodiment which does not require an inductive coupling via the filling hose requires computer systems which are similarly designed on both sides and which in each case have a reading device for transponders and are connected to one another on-line or off-line via an additional data link. In this case it is sufficient to identify each connecting hose with reading transponders on both sides in order to achieve the object of reliable mixing protection.