The first part of the description starts with the basic configuration of the fault-tolerant S7-400H programmable controller and the components making up the S7-400H base system. We then describe the hardware components with which you can expand this base system. The second part describes the software applications with which you can configure and program the S7-400H. In addition, a description is given of the additions and extensions, compared to the S7-400 standard system, that you will require for programming your user program in order to be able to react specifically to the properties of the S7-400H that enhance availability
