After working with siemens PLC many years, we had to use a small PLC with possibility to connect a vehicle CAN-bus. We choose a PLC from WAGO (750-837).
In this 750-8xx family of wago I/O System you can scale the input/output devices very effectiv. After using d the CAN-Device we often use the Ethernet-Device (750-841) for coupling any I/O to PC-Applications in VB or java.