Functional element for connecting the PKE with trip blocks PKE-XTU(W)A(CP)-... to Modbus RTU, attachment to motor protection switch PKE, messages: switch position PKE, all phase currents in %, thermal load in %, tripped messages (overload, short circuit,...), set value overload release, set value short circuit release, type of trip block, trip and switch-on counter, commands: remote shutdown of motor protection switch, plug with connection terminals included in delivery, can be used for PKE12, PKE32, PKE65