Chapter 5
System functions are stored in ?
File 0
File reserved by the processor.
File 1
File that contains the main ladder program?
File 2
Files contains the subroutine ladder program.
Files 3-255
Graphical language.
Functional Block. Ladder diagram Sequential function chart.
Digital devices
Have only two positive values. Have signals as shown in figure (A)
Analog devices
Have signal as shown in figure (B) Have infinite number of positive values.
Personal computers can be used as a PLC programmer?
True
The examine if closed (XIC) instruction is also called the examine on instruction.
True
Identify the types of information that can be stored in the file 0 of the program files.
Type of processor. Processor password. I/O configuration.
identify the true statements about a scan cycle time.
it indicates how fast the controller
examine if open (XIO) instruction.
which instruction does the symbol in the given figure represent?
File (_____________) stores the counter accumulated and present values and status bits.
5
File (___________) stores the length pointer position and status bit of specific instructions such as shift registers and sequencers.
6
File (___________) is used to store whole number values and bit information.
7
File (_________) is used to store fractional numerical data or numerical values grater than 32,767.
8
which of the following number system can be used to represent the address of a real input or output?
Decimal octal hexadecimal
which of the following statements are true of the input image table file.
Each connected input has a bit in the input image table file that corresponds exactly to the terminal to which the input is connected. if the input is on its corresponding bit in the table is set to 1. If the input is off its corresponding switch connected is open.
select the true statements about internal outputs in a PLC.
Internal outputs are ON/OFF signals generated by programmed logic. Internal outputs are the internal storage bits.
What are the advantages of using internal outputs?
Internal outputs can minimize outputs module points requirements whenever practical. they can be used in situations where an output instruction is required in a program but no physical connection to a field device is needed. internal outputs use a single bit of memory location.
The output energize OTE instruction look and operates like a.
Relay coil.
Textual Language
Structures text Instruction list.
select the true statements about OTE Instruction.
The OTE instruction signals the PLC to energize the output. The OTE instruction is associated with a memory bit. The OTE instruction signal the PLC to de energize the output.
Identify the True statement about memory structures of Allen-Bradley PLC's.
The SLC 500 series of controllers used in a rack based memory structure. Allen-Bradley PLCs have two different types of memory structure.
Which of the fooling statements are true of program files in a SLC 500 controller?
The information stored in file 2 defines how the controller should be operated. File 1 not accessible to user.
Select the true statements about the limitations on branch instructions in a PLC.
The limitation on the number of rungs is memory size. The PLC will not allow for programing of vertical contacts.
identify the true statement about the nature of scan in Allen-Bradley PLCs
The processor examines input and output instruction from the first command top left in the program rung by rung
Identify the purpose of a verify operation.
The verify operation is used to check the ladder program for errors.
identify the true statements about the examine if closed (XIC) instruction.
When the instruction is associated by an internal relays address the status of the bit is dependent on the logical status of the internal bit. When the instruction is associated with a physical inputs, the instruction will be set to 1 when a physical input is present.
