User:Amon edward

Rack Assembly Most medium to large PLC systems are assembled such that the individual components – CPU, Input/Output, Power Supply – are modules that are held together within a rack. In smaller PLC systems – all of these components may be contained in a single housing or “brick” – these smaller systems are sometimes referred to as “bricks” or “shoebox” PLCs. Power Supply The power supply provides power for the PLC system. The power supply provides internal DC current to operate the processor logic circuitry and input/output assemblies. Common power levels used are 24V DC or 120 VAC. Processor (CPU)