LAB SOURCE relay bit instructions Training PLC Allen Bradley

RSLOGIX 5000 MAINTENANCE AND TROUBLESHOOTING COURSE

INTERPRETING LADDER LOGIC
Summary Tasks
After completing this lesson, you will be able to interpret simple ladder logic
programs that use basic conditional and retentive bit-level instructions. Since
ladder logic is the one of programming languages used to program Control
Logix system, knowing how to interpret this language make troubleshooting
problems associated with this systems much easier.

Exercise 1
In the exercise you will interpret simple ladder logic programs that use basic
conditional and retentive bit-level instructions.

Directions:
1. Create new Project, namely: BBFE_Training_Day2. Set all controller
properties and I/O Configuration as described in previous section.
2. Create tags as follow:

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Name: SW0, Tag type Base, Data Type: BOOL

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Create same format type namely SW1, SW2, SW3

Ladder Logic

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2

Lab Work – Ladder Logic

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Name: Light0, Tag type Alias, Alias For: Local:3:O.Data.0. Create
another following tags with same format:

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Name: Light1, Tag type Alias, Alias For: Local:3:O.Data.1

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Name: Light2, Tag type Alias, Alias For: Local:3:O.Data.2

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Name: Light3, Tag type Alias, Alias For: Local:3:O.Data.3

3. Create a new routine in MainProgram, namely: Ladder_1. Select type:
Ladder Diagram.

Department of Engineering Physic – ITB


RSLOGIX 5000 MAINTENANCE AND TROUBLESHOOTING COURSE

4. Create ladder diagram as following figure:

5. In MainRoutine add JSR (Jump to Sub Routine) ladder to call Ladder_1
Routine. Add new tag SW_Ladder_1 that has same format with SW0

6. Download and go online to this project.
7. Place controller in Remote Run Mode.
8. Toggle SW_Ladder_1 to bit = 1
9. Interpret the instruction in the program file by answering the following
questions:
A. Close SW0 (By toggle SW0 to bit = 1). When SW0 is closed, which
light(s) turn on?
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B. Open SW0 (by toggle SW0 to bit = 0). When SW0 is open, what
happen to Light0 and Light1?
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C. Where is the bit corresponding to Light0 located?
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Ladder Logic

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Lab Work – Ladder Logic
D. Close SW1 (by toggle SW1 to bit =1). What happens to Light2?
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E. Open SW1 (by toggle SW1 to bit =0). What happens?

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F. Close SW2 (by toggle SW2 to bit =1). What happens?
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G. Open SW2 (by toggle SW2 to bit =0). What happens?
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H. What must be done to turn Light3 off?
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Department of Engineering Physic – ITB