Page 266 - Programmable Logic Controllers, Fifth Edition - Mobile version

CHAPTER 11 REVIEW QUESTIONS

1. Explain the function of math instructions as applied destination if N7:3 contains a value of 15 and N7:4
to the PLC. contains a value of 4?
2. Name the four basic math functions performed by 9. With reference to the instruction of Figure 11-32,
PLCs. what is the value of the number stored at N7:20 if
3. What standard format is used for PLC math N7:3 contains a value of 2345?
instructions? 10. With reference to the instruction of Figure 11-33,
4. Would math instructions be classified as input or what will be the value of each of the bits in word
output instructions? B3:3 when the rung goes true?
5. With reference to the instruction of Figure 11-28, 11. With reference to the instruction of Figure 11-34,
what is the value of the number stored at source B what is the value of the number stored at N7:101?
if N7:3 contains a value of 60 and N7:20 contains a 12. With reference to the instruction of Figure 11-35,
value of 80? list the values that will be stored in file #N7:10
6. With reference to the instruction of Figure 11-29, when the rung goes true.
what is the value of the number stored at the desti-
nation if N7:3 contains a value of 500? NEG
7. With reference to the instruction of Figure 11-30, NEGATE
N7:3
what is the value of the number stored at the des- Source N7:20
Destination
tination if N7:3 contains a value of 40 and N7:4
contains a value of 3? Figure 11-32 Instruction for Question 9.
8. With reference to the instruction of Figure 11-31,
what is the value of the number stored at the CLR
CLEAR
ADD Destination B3:3
ADD 0000111100001111
Source A N7:3
Source B N7:4 Figure 11-33 Instruction for Question 10.
Destination N7:20
SQR
Figure 11-28 Instruction for Question 5. SQUARE ROOT
Source A N7:101
SUB Destination N7:105
SUBTRACT 4
Source A N7:3
Source B 338 Figure 11-34 Instruction for Question 11.
Destination N7:20
FAL
Figure 11-29 Instruction for Question 6. FILE ARITH/LOGICAL EN
DIV Control R6:0 DN
DIVIDE Length 5
Source A N7:3 Position 0 ER
Source B N7:4 Mode All
Destination N7:20 Destination #N7:10
Expression
#N11:0 + 10
Figure 11-30 Instruction for Question 7.
File #N11:0
MUL
MULTIPLY 328
Source A N7:3 150
Source B N7:4 10
Destination N7:20 32
0
Figure 11-31 Instruction for Question 8. Figure 11-35 Instruction for Question 12.

Math Instructions Chapter 11 247

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