Page 402 - Programmable Logic Controllers, Fifth Edition - Mobile version

PART 5 REVIEW QUESTIONS

1. Construct a ControlLogix ladder rung with a math tag named Cases (value 10) by the constant 24 and
instruction that executes when a toggle switch is store the answer in the tag named Cans.
closed to add the tag named Pressure_A (value 680) 4. Construct a ControlLogix ladder rung with a com-
to the constant of 50 and store the answer in the tag pare instruction that will energize a pilot light output
named Result. anytime the value stored at Data_3 is 60.
2. Construct a ControlLogix ladder rung with a math 5. Construct a ControlLogix ladder rung with a compare
instruction that executes when two normally open limit instruction that will energize a pilot light output
switches are closed to subtract the tag named Count_1 anytime the value stored at Data_2 is not the same as
(value 60) from the tag named Count_2 (value 460) that stored at Data_6.
and store the answer in the tag named Count_Total. 6. Construct a ControlLogix ladder rung with compare
3. Construct a ControlLogix ladder rung with a math instructions that will energize a pilot light output
instruction that executes when either one of two anytime the pressure of a system goes above 300 psi
normally open pushbuttons is closed to multiply the or below 100 psi.

PART 5 PROBLEMS

1. While checking the operation of the parts tracking value of the three counters. Write a ControlLogix
system (Figure 15-80) with the Monitor Tags win- program that uses multiply and add instructions to
dow, you note that the value of Conveyor_Sensor_1 calculate the sum of the parts.
remains at 1 with parts passing by. What can you 3. A single pole switch is used in place of the two
surmise from this? Why? pushbuttons for the variable preset timer program
2. Three conveyors are delivering the same parts in dif- (Figure 15-91). When this switch is closed the
ferent packages. A package can hold 12, 24, or 18 timer is to be set to 10 seconds and when open to
parts. Proximity switches installed on each of the 15 seconds. Make the necessary changes to the
conveyor lines are used to advance the accumulated program.

Math, Comparison, and Move Instructions Part 5 383

pet73842_ch15_333-394.indd 383 03/11/15 7:34 PM