The Allen-Bradley 1785-L40B PLC-5 Controller Processor mounts on a PLC-5 chassis, and its high user memory words makes it ideal for use with medium to large automation applications. The high user memory also grants the processor high I/O capacity, making it capable of handling up to 29 PLC-5 racks, including the local rack where the controller resides. Each of its combination ports may be used with separate networks, and the serial communication channel allows for point-to-point interface.