Siemens simatic dp interface module electronic module terminal module siemens 6es7151 7aa21 0ab0 the siemens 6es7151 7aa21 0ab0 is a simatic dp im151 7 cpu for the simatic et200s io system the im 151 7 cpu interface module is an intelligent pre processing unit i slave it enables you to decentralise control taskswhen attached to the et 200s the im 151 7 cpu can exercise full and if necessary independent control over a process related functional unit and can be used as a stand alone