Each input or output instruction is assigned an address (shown below the instructions in Fig. 1, on page 22) indicating the location in the PLC memory where the state of that instruction is stored.

Higher amperage relay output modules and an 8-point input simulator module are now available from AutomationDirect for the Click series stackable micro brick PLCs.

Does the module's output correspond correctly to its input? Determine that by forcing the PLC output to 10%, 25%, 50%, 75%, and 90% and measuring on the output terminals at the corresponding range.

High speed, multi-channel digital isolators from Silicon Labs, are suited to programmable logic controller (PLC) applications, including industrial I/O modules, CNC machines and servo motor control.