Bulletin 1747 SLC™ 500 PLC is a chassis-based,  modular family of controllers and I/O. With multiple processor choices, numerous power supply options and extensive I/O capacity, the SLC 500 family provides a powerful solution for mid-range stand-alone or distributed industrial control. As one of the first full-featured small controllers on the market, it remains the gold standard in logic controllers more than a decade after its introduction.