SIMATIC S7-300, Cable guide LK 393 for EX (I) modules Connections L+ and M are intrinsically safe the terminals fed in, 5 units per packing unit SIMATIC ET 200M is a modular and universally applicable I/O system for the control cabinet in IP20, which can be used as a central I/O on an S7-300 as well as in a distributed configuration on a PROFINET or PROFIBUS ET 200M interface module. As many as 12 IO modules can be inserted into each station. The standardized setup of all modules considerably simplifies logistics and stocking of spare parts. Accessories for SIMATIC S7-300