Unit 1: Basic Programmable Logic
Controller (PLC)
A programmable logic controller is a specialized ___________ used to control machines and processes. -
Answer-computer
A PLC system eliminates much of the hard wiring that was associated with conventional relay control
circuits. (T or F) - Answer-True
PLC control systems are more reliable and easier to troubleshoot than relay based control systems. (T or
F) - Answer-True
A PLC operates in real-time. (T or F) - Answer-True
The fixed I/O module configuration: - Answer-is typical of small PLC units, has no separate removable
units, is limited as to the availability of modules.
A proprietary PLC system allows the system to be connected easily to devices made by other
manufacturers. (T or F) - Answer-False
In which module of a PLC is the decision making performed? - Answer-processor module
The input interface module - Answer-conditions the signal received from a field device
