Lab 2-2: Micrologix PLC Hardware - Gulf Coast State College

Lab 2-2, Page 1

Study the Safety Policy Statement (Toyota Electricity 102)

OBJECTIVES:

Upon completion of this lab you should be able to:

Connect the lab top computer to the PLC trainer.

Identify the main parts of the Micrologix PLC trainer.

Identify addresses for terminals on the PLC and I/O modules

Wire a control panel box to the PLC.

Test the thumbwheel switch.

Test and troubleshoot wiring to the PLC without a program.

READING & STUDY MATERIAL: (best viewed in the order listed) Programmable Logic Controllers Hardware and Programming by Max Rabiee 2

nd ed.

1. Chapter 1 Programmable Logic Controller (PLC) Overview

2. View the powerpoint presentation by Rabiee: Ch01.ppt 3. Chapter 2 PLC Selection, Components, and Communications

4. View the powerpoint presentation by Rabiee: CH02.ppt 5. Chapter 4 Input/Output and Motor Control

6. View the powerpoint presentation by Ragiee: CH04.ppt 7. View the powerpoint presentation: Lab 2 – PLC Trainer.ppt

8. View the powerpoint presentation: Lab 2 - Micrologix Hardware.ppt 9. View the powerpoint presentation: Lab 2 - Micrologix Addressing.ppt

INTRODUCTION:

When wiring control panels to be permanent, it is important to be neat keeping the wires down against the panel and eliminate excessive length. Panduit (wire duct) is used to keep the wires from crossing over components and keep the panel neat to make troublshooting easier. Wire tags should be used to number the wires with a corresponding number printed on the electrical drawing. Wire ties can be used to bundle wires into a cable. Wire nuts should be avoided, making all connections on terminal blocks. Electrical tape should not be used except for emergency repairs. Wiring to a PLC is straight forward Here are some rules for wiring PLCs.

1. Only one output device to one output terminal 2. Outputs can output only 1 amp. Use a relay to control more current 3. Inputs are common to +24 VDC 4. Outputs are common to ground 5. Inputs are wired to normally open devices. 6. Wire only one input to each input terminal 7. Input and output voltage must match the I/O module 8. Some input devices such as proximity sensors require a pull up resistor

Gulf Coast State College

EST 2542C Programmable Logic Controllers

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Lab 2-2: Micrologix PLC Hardware

Lab 2-2, Page 2

LAB PROCEDURE:

PART 1: Identify the following components on the lid of the PLC CASE Trainer

Watch the power point and identify the following

A. ______________________ B. ______________________ C. ______________________ D. ______________________ E. ______________________ F. ______________________ G. ______________________ H. ______________________

A B C D E F G H

Lab 2-2, Page 3

PART 1 (Continued): Identify the following components on the base of the PLC CASE Trainer

Watch the power point and identify the following A. ______________________ B. ______________________ C. ______________________ D. ______________________ E. ______________________ F. ______________________ G. ______________________ H. ______________________ I. ______________________ J. ______________________ K. ______________________ L. ______________________ M. ______________________ N. ______________________ O. ______________________ P. ______________________ Q. ______________________ R. ______________________ S. ______________________ T. ______________________

A B C D E F G H I J K L

M N O P Q R S T

Lab 2-2, Page 4

PART 2: Working with Electrical Drawing of the PLC Trainer

Study the drawing of the PLC Trainer and trace some of the wires . Being able to troubleshoot reqiures an understanding of reading drawings and finding the components and wires on the panel. After checking voltages for proper operation, answer the folllowing questions.

1. How many inputs are there on the PLC “brick” ? _______________________________________ 2. What is the first input (LSB) address? _______________________________________________

3. How many outputs are there on the PLC “brick” ? ______________________________________

4. What is the last (MSB)output address? ______________________________________________

5. What address are used by the thumbwheel switch? ____________________________________

6. What is the address of the switch on the control panel? _________________________________ 7. What Color wire are reserved for +24vdc and -24vdc ground? _____________________________

COM 0 I/1

24 VDC POWER

COM I/2

I/3 I/4 I/6 COM 2 I/9

COM 1 I/5 I/7 I/8 I/10

I/11

1764-24BWA LSP SERIES C

0-9

Green Green Green Red Blue

+ -

24 VDC POWER SUPPLY 120 VAC L1

L2

GND

Black White

Green

RED BLACK

Black

Green Black

White

Black Black Black

Thumbwheel

Switch

RED RED RED RED RED

CB1 2a

CB2 4a

+24 VDC Output

85-265

L1

L2 VDC 0 VDC 1 VDC 2 VDC 3

O/3 O/1 O/0 O/2 O/4 O/6

VAC 4 O/5 O/7 O/8

VAC 5 O/9 O/11

O/10 24BWA

Black Black Black Black

I/0

0-9

1 2 4 8

RED RED RED RED

RED

1 2 4 8

Thumbwheel

Switch

Control Panel

Switches

Control Panel

Lights

Red Brown Purple Blue Black Orange Yellow Green Brown Blue Orange Yellow Purple

Brown Blue Orange Yellow Purple

Lab 2-2, Page 5

Part 3: Testing the Control Boxes on the PLC Trainer 1. Press each button and check to see if the LED light in the face of the PLC comes on. 2. To test the output lights, place a temporary wire from VAC/VDC to terminal O/0. The red light come on. Next move the jumper from VAC/VDC5 to terminal O/1, the green light should come on. Continue the procedure for the rest of the lights.

Red Green Green Yellow Blue

Black White Green

DANGER 120 VAC

Micrologix 1500 PLC

+ 24 VDC

-

Brown

Blue

Orange

Yellow

Red Green Black Black Switch

Red

Black

Brown

Blue

Orange

Yellow

Purple

Purple

Temporary Jumper

CAUTION: Don’t

Touch the 120 VAC

terminals

Lab 2-2, Page 6

Part 4: Testing the Thumbwheel switch The thumbwheel switch allows an operator to enter data for timers, counters, program steps, temperatures, rpm, etc. These switches come in one digit units that can be assembled into 2, 3, or more digits. One unit allows the operator to enter number from 0-9, two units 0-99, etc. Each unit mechanically creates a BCD code (8-4-2-1) requiring four inputs to the PLC. Turn on the PLC and the 24vdc power and rotate first unit from 0-9 and watch the lights on the PLC, then rotate second unit from 0-9 and watch the lights on the PLC. The second unit will only go from 0-7 since the 8 wire is not connected. The chart below shows the BCD output of the switch.

Dec. BCD

8 4 2 1

----------------------

0 0 0 0 0

1 0 0 0 1

2 0 0 1 0

3 0 0 1 1

4 0 1 0 0

5 0 1 0 1

6 0 1 1 0

7 0 1 1 1

8 1 0 0 0

9 1 0 0 1

Terminals on “Brick”

Black

Brown

Red

Orange

Yellow

w

Green

Blue

Purple

I:0/0

I:0/1

I:0/2

I:0/3

I:0/4

I:0/5

I:0/6

+ 24 vdc

C

C

1

2

4

8

1

2

4

8

Units

Rt. Side

Tens

Lt. Side

White

Black

24 vdc ground

Lab 2-2, Page 7

Part 5: Testing the Limit Switches

1. Locate the 4 limit switches. 2. Move the pistons from the two cylinders to mid stroke off the limit switches. 3. Press LS-1 to see if the LED light “1” comes on 4. Press LS-2 to see if the LED light “2” comes on 5. Press LS-3 to see if the LED light “3” comes on 6. Press LS-4 to see if the LED light “4” comes on

Blue Green Brown Purple

LS-4 LS-3 LS-2 LS-1

Red

+24VDC

- 24VDC Ground

Lab 2-2, Page 8

Part 6: Testing the Fan

Place a temporary jumper from VAC/VDC5 to terminal 0/11. The fan should run.

Part 7: Testing the Solenoid Valves

Place a temporary jumper from VAC/VDC5 to terminal 0/8. A solenoid should click. Identify which solenoid is wired to each PLC terminal. O/8 Solenoid ____________ O/9 Solenoid ____________ O/10 Solenoid ____________

Solenoids

Lab 2-2, Page 9

Part 8: Testing the Photo Sensor and Proximity Sensor.

1. To test the photosensor, place an object infront of the sensor to block the beam. The LED #6 on the input module should light. 2. To test the proximity sensor, place an metal object such as a coin against the head of the sensor. The LED #7 on the input module should light.

Red

+24VDC

- 24VDC Ground

Proximity Sensor

Photo Sensor

4700

4700

Lab 2-2, Page 10

PLC Addresses:

The addresses for the PLC trainer are shown in the chart below. This charts will assist you throughout the course in finding addresses for components wired to the I/O of the PLC trainer.

Output Output Input Input

Addresses Description Addresses Description

O:0/0 Top Light - Red I:0/0 Units Thumbwheel Switch - Weight 1

O:0/1 2nd Light - Green I:0/1 Units Thumbwheel Switch - Weight 2

O:0/2 3rd Light - Green I:0/2 Units Thumbwheel Switch - Weight 4

O:0/3 4th Light - Yellow I:0/3 Units Thumbwheel Switch - Weight 8

O:0/4 5th Light - Blue I:0/4 Tens Thumbwheel Switch - Weight 1

I:0/5 Tens Thumbwheel Switch - Weight 2

O:0/8 Solenoid SOL-1 I:0/6 Tens Thumbwheel Switch - Weight 4

O:0/9 Solenoid SOL-2

O:0/10 Solenoid SOL-3 I:0/7 Top Panel Pushbutton - Red

I:0/8 2nd Panel Pushbutton - Green

O:0/11 Fan I:0/9 3rd Panel Pushbutton - Black

I:0/10 4th Panel Pushbutton - Black

O:2/0 Segment A I:0/11 Bottom Panel Switch

O:2/1 Segment B

O:2/2 Segment C I:1/1 Limit Switch - LS1

O:2/3 Segment D I:1/2 Limit Switch - LS2

O:2/4 Segment E I:1/3 Limit Switch - LS3

O:2/5 Segment F I:1/4 Limit Switch - LS4

O:2/6 Segment G

I:1/5

I:1/6 Photo Sensor

I:1/7 Proximity Sensor

Lab 2-2, Page 11

SUMMARY: Control panels containing programmable logic controller with power supplies, relays, contactors, switches, lights, touch screens and special components are custom built for the application. In addition PLCs are placed in panels for machine control replacing the older technology of electro-mechanical or digital circuit cards which are fixed automation, PLC’s allow for change and upgrades by simply wiring up additional inputs and outputs and modifying the program. Development and design time are drastically reduced compared to the older fixed control circuits. Testing and troubleshooting is also easier and dependability is much higher. PLC’s provide four features for wiring a control panel.

Isolation (Opto-isolation for each terminal)

Termination (terminal strips that snap off the plc)

Signal conditioning ( changes user voltages, 24vdc or 120 vac to 5 vdc within the PLC)

Indication (LED lights to indicate signal receiver or sent) Troubleshooting the PLC wiring can be done without the use of a program, however the program can be monitored to troubleshoot the application as well as monitor input and outputs. The use of a voltmeter is the number one tool for checking wiring to and from the PLCs I/O. Always check for power first and check for proper grounds, then trace the voltage to the PLC inputs or out to the loads.

LAB CREDIT:

Demonstrate that all items tested operate on the PLC trainer