PLC's Chapter 5 Flashcards
Explain Rack-based memory
With rack-based memory structures addresses are derived using the rack number, the I/O module slot number and the screw terminal number where the I/O device is wired. With rack-based memory structures addresses are derived using the rack number, the I/O module slot number and the screw terminal number where the I/O device is wired.
Explain Tag-based memory
With tag-based memory structures all data are assigned a variable name called a tag. A program can be developed using only tag names but you must assign input and output terminals to input and output tags before the program can be executed
The memory space can be divided into two broad categories: ____ files and ____files.
The memory space can be divided into two broad categories:
program files and Data files.
Program files are the ___ of processor _____ where ladder logic programming is _____.
Program files are the areas of processor memory where ladder logic programming is stored.
Program files are the___of the _____ memory that stores the user ____logic program. The program accounts for most of the ____memory of a given PLC system.
Program files are the part of the processor memory that stores the user ladder logic program. The program accounts for most of the total memory of a given PLC system.
The Data file _____ of the processor’s______stores ____and ____status, processor status, the status of various bits, and numerical data.
The Data file portion of the processor’s memory stores input and output status, processor status, the status of various bits, and numerical data.
The PLC-5 and SLC 500 ____all ____ in global data _____ and are based on __-bit operations.
The PLC-5 and SLC 500 store all data in global data tables and are based on 16-bit operations.
You ____these ____by specifying the _______of the data you want.
You access these data by specifying the address of the data you want.
The _______ in the ____data file and the ____
____ for I/O modules mounted in the chassis.
The addresses in the output data file and the input
data file are potential locations for I/O modules mounted in the chassis.
The ____data file ____information about the _____ status.
The status data file contains information about the processor status.
The_____________ stores bit status and ___________ serves for _______when using internal outputs.
The bit data file stores bit status and frequently serves for storage when using internal outputs.
The_____ file____ the timer ____ and timer data.
The timer file stores the timer status and timer data.
The_____file ____ the ______status and _____
data.
The counter file stores the counter status and counter
data.
The ____image table is allocated to _____the on/off status of connected discrete inputs.
The input image table is allocated to storing the on/off status of connected discrete inputs.
If the input is on (switch closed), its corresponding
bit in the table is set to__.
If the input is on (switch closed), its corresponding
bit in the table is set to 1.
If the input is off (switch open), the corresponding
bit is cleared, or reset to __.
If the input is off (switch open), the corresponding
bit is cleared, or reset to 0.
The ________table is allocated to _____ the on/off status of connected discrete outputs.
The output image table is allocated to storing the on/off status of connected discrete outputs.
If the program calls for an output to be ON, its corresponding bit in the table is set to ____.
If the program calls for an output to be ON, its corresponding bit in the table is set to 1.
If the program calls for an output to be OFF, its corresponding bit in the table is set to __.
If the program calls for an output to be OFF, its corresponding bit in the table is set to __.
Simulated operation of the _________ table _____status of connected discrete outputs.
Simulated operation of the output image table on/off status of connected discrete outputs.
Typically,____PLCs have a ____ number of _____ and ______.
Typically, micro PLCs have a fixed number of inputs and outputs.
During ____ program scan cycle, the processor reads all the ____, takes these _____, and _______ or _______ the _____ according to the user program.
During each program scan cycle, the processor
reads all the inputs, takes these values, and energizes or de-energizes the outputs according to the user program.
The___ it takes to ____ a scan cycle is a measure of how___the controller can _____ to changes in inputs.
The time it takes to complete a scan cycle is a measure of how fast the controller can react to changes in inputs.
The scan time is a function of: • The speed of the processor module • The length of the ladder program • The type of instructions executed • The actual ladder true/false conditions
The scan time is a function of: • The speed of the processor module • The length of the ladder program • The type of instructions executed • The actual ladder true/false conditions
