PLC Exam
What are the major parts of a plc? - Answer-The CPU, I/O, power supply, and programming device
Architecture - Answer-Refers to PLC hardware or software
Open architecture - Answer-Allows the system to be connected easily to devices and programs made by
other manufacturers
Closed architecture - Answer-A system whose design is proprietary making it difficult to connect to other
systems
Fixed I/O - Answer-Small PLC that comes in one package with not separate removable units. The
processor and I/O are packaged together
Modular I/O - Answer-A PLC that is divided by compartments into which separate modules can be
plugged
Power supply - Answer-Provides DC power to all modules that plug into the rack
CPU or processor - Answer-A microprocessor for implementing the logic and controlling the
communications among the modules
PLC scan cycle - Answer-Reads inputs -> executes program -> diagnostics & communication -> updates
outputs
,I/O (Input/Output) system - Answer-Forms the interface by which field devices are connected to the
controller.
I/O (Input/Output) system - Answer-Forms the interface by which field devices are connected to the
controller
Programming device - Answer-Used to enter the desired program into the memory of the processor
Personal computer (PC) - Answer-The most commonly used programming device
Program - Answer-A series of instructions that directs the PLC to execute actions
Relay ladder logic - Answer-The standard programming language, is based on electromagnetic relay
control
Address - Answer-Where an input or output device is conncected
PC vs PLC - Answer-PLC is designed to operate in the industrial environment with wide ranges of
ambient temperature and humidity
Human machine interface (HMI) - Answer-Software that allows the user to monitor and control the
process
Programmable Automation Controllers (PACs) - Answer-Combine PLC ruggedness with PC
functionality
Nano - Answer-Smallest size with less than 15 I/O
, Micro - Answer-15-128 I/O
Medium - Answer-128-512 I/O
Large - Answer-Over 512 I/O
Single ended application - Answer-One PLC controlling one process
Multitask application - Answer-One PLC controlling several processes
Control management application - Answer-One PLC controlling several others
Memory - Answer-Part of a PLC controller that stores data, instructions, and the control program
Memory size - Answer-Expressed in K values
1K = - Answer-1024
Amount of memory required depends on - Answer-• Number of I/O points
used
• Size of control
program
• Data-collecting
requirements
What are the major parts of a plc? - Answer-The CPU, I/O, power supply, and programming device
Architecture - Answer-Refers to PLC hardware or software
Open architecture - Answer-Allows the system to be connected easily to devices and programs made by
other manufacturers
Closed architecture - Answer-A system whose design is proprietary making it difficult to connect to other
systems
Fixed I/O - Answer-Small PLC that comes in one package with not separate removable units. The
processor and I/O are packaged together
Modular I/O - Answer-A PLC that is divided by compartments into which separate modules can be
plugged
Power supply - Answer-Provides DC power to all modules that plug into the rack
CPU or processor - Answer-A microprocessor for implementing the logic and controlling the
communications among the modules
PLC scan cycle - Answer-Reads inputs -> executes program -> diagnostics & communication -> updates
outputs
,I/O (Input/Output) system - Answer-Forms the interface by which field devices are connected to the
controller.
I/O (Input/Output) system - Answer-Forms the interface by which field devices are connected to the
controller
Programming device - Answer-Used to enter the desired program into the memory of the processor
Personal computer (PC) - Answer-The most commonly used programming device
Program - Answer-A series of instructions that directs the PLC to execute actions
Relay ladder logic - Answer-The standard programming language, is based on electromagnetic relay
control
Address - Answer-Where an input or output device is conncected
PC vs PLC - Answer-PLC is designed to operate in the industrial environment with wide ranges of
ambient temperature and humidity
Human machine interface (HMI) - Answer-Software that allows the user to monitor and control the
process
Programmable Automation Controllers (PACs) - Answer-Combine PLC ruggedness with PC
functionality
Nano - Answer-Smallest size with less than 15 I/O
, Micro - Answer-15-128 I/O
Medium - Answer-128-512 I/O
Large - Answer-Over 512 I/O
Single ended application - Answer-One PLC controlling one process
Multitask application - Answer-One PLC controlling several processes
Control management application - Answer-One PLC controlling several others
Memory - Answer-Part of a PLC controller that stores data, instructions, and the control program
Memory size - Answer-Expressed in K values
1K = - Answer-1024
Amount of memory required depends on - Answer-• Number of I/O points
used
• Size of control
program
• Data-collecting
requirements
