ABB is increasing its PLC offering with the launch of the AC500 system. There are three products in the range: the AC500 PLC, the S500 I/O module, and the CP500 HMI terminal. Available through ABB's low voltage products division, the AC500 system will complement ABB's existing AC31 PLC and the AC800 DCS family of controllers. The AC500 can be supplied with three different CPUs: PM571 (micro), PM581 (mini) and PM591 (midi).