32 kB working memory, 248 inputs, 124 outputs
The Siemens 6ES7313-6BE00-0AB0 is a SIMATIC S7-300 CPU 313 with 32 kbyte integrated working memory for program and data, expandable to a max of 16 kbyte for program size. That 32 kB is the working memory the CPU uses at runtime — enough for mid-size machine logic with a few hundred I/O points and a PID loop or two. It handles up to 248 digital inputs and 124 digital outputs, giving you headroom for a machine with several fieldbus nodes or local I/O racks. The CPU supports LAD, FBD, SCL, STL, GRAPH, and HiGraph® programming languages, so your team can use ladder for the safety interlocks and structured text for the math blocks.
Programming and communication
Programming is done via STEP 7 V5.1 SP2 or higher. The CPU has an integrated RS 485 (RS 422/485 X.27) interface for MPI — though MPI is listed as not supported on this variant, so you'll use the RS 485 for point-to-point or PROFIBUS DP via a CP. It supports ASCII, 3964(R), and RK512 protocols over the PtP interface. The CPU supports up to 1 CP for PROFIBUS/industrial Ethernet, 2 CPs for LAN, and 4 CPs for PtP. The integrated 32 kB working memory is not expandable.