Control Checking the PLC operating

4.3 Checking the PLC operating


4.3.1. Equipment and materials for electrical installations must be installed in such a way that does not reduce the Index of Protection (IP) as determined.

In installing equipment and materials shall be in accordance with a predetermined IP. IP Code consists of two digits and is always listed on the equipment body. The first digit shows the degree of protection rate against solid objects and dust. The second digit shows the degree of protection against liquids. In some countries a third digit is being added. in this case it shows the degree of mechanichal protection.



Example: A rating of IP65 means a degree of protection 6 against solid objects and a degree of protection 5 against liquids.


Classification of the Index of Protection is as follows:

Warning

The IP rating is valid with standard environmental conditions.Special protections could be required in special hazardous areas such as refineries, mines, blast furnace tcc.

Protection against solid objects
1st digit	Description	Definition
0	No protection	No special protection
1	Protection against solid objects larger than 50mm	Any extended part of body, such as the hand (the protection does not include intentional access). Solid objects with a diameter larger than 50mm.
2	Protection against solid objects larger than 12mm	Fingers or similar objects with a maximum lenght of 80mm. Solid objects with a diameter larger than 12mm.
3	Protection against solid objects larger than 2.5mm	Tools, wires and similar with a maximum diameter or thickness of 2.5mm. Solid objects with a diameter larger than 2.5mm
4	Protection against solid objects larger than 1.0mm	Wires or strips with a maximum thickness of 1.0mm. Solid objects with a diameter larger than 1.0mm
5	Protection against dust	Entering of dust is not completely prevented, but dust does not enter in such a quantity to disrupt the normal operation of the device.
6	Total protection against dust	No dust entering is possible.

Protection against liquids
2nd digit	Description	Definition
0	No protection	No special protection
1	Protection against drops of water	Vertical drops of falling water must not have any damaging effect
2	Protection against drops of water when tilted up to 15°	Vertical drops of falling water must not have any damaging effect, when the device is tilted up to 15°from normal position.
3	Protection against spraying water	Water spray falling at an angle up to 60° from vertical must not have any damaging effect.
4	Protection against splashing water	Water splashed towards housing from any direction must not have any damaging effect.
5	Prot against water jets	A water jet from a a nozzle from any direction must not have any damaging effect.
6	Protection against strong sea water	Strong sea water or a powerful water jet from any direction must not have any damaging effect.
7	Protection against immersion	Entering of water in such a quantity to damage the device must not be possible when the device itself is dropped into water for a limited period at defined pressure conditions.
8	Protection against continued submersion	The device may be immersed in water for a long duration at the conditions specified by manufacturer.

Table 4.6. Index of Protection

4.3.2. Verifying the performance of the PLC and associated equipment

After the PLC is programmed, the next step is to run the PLC and the equipment and then observe and check whether the PLC and the equipment was operating properly in accordance with the expected control performance.


4.3.3. Identifying irregularities

After checking the performance of the PLC and the equipment, if their performance is not as expected as soon do the identification of deviations that occurred and noting in a brief report.


4.3.4. Define alternative solutions

Based on the record that has been made about the discovery of performance deviations that occur, the next step is to conduct analysis to find an alternative solution or solutions to overcome these deviations.

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Schematic Liquid Crystal Display LCD

The HD44780 dot-matrix liquid crystal display controller and driver LSI displays alphanumeric characters and symbols. It can be configured to drive a dot-matrix liquid crystal display when interfaced with a processor. A single HD44780 can display up to one 8-character line or two 8-character lines. The HD44780 supports 8 dot character fonts and 32 5 ´ 10 dot character fonts for a total of 240 different character fonts.

2.1 Function Description of LCD
The following section will introduce the user with some of the important features of the liquid crystal display, that are important for interfacing with the liquid crystal display through software.

2.1.1 Registers of LCD

The HD44780 has two 8-bit registers, an instruction register (IR) and a data register (DR). The IR stores instruction information, such as display clear and cursor shift, and address information for display data RAM (DDRAM) and character generator RAM (CGRAM). The DR temporarily stores data to be written into DDRAM or CGRAM and temporarily stores data to be read from DDRAM or CGRAM. Data written into the DR is automatically written into DDRAM or CGRAM by an internal operation. The DR is also used for data storage when reading data from DDRAM or CGRAM. When address information is written into the IR, data is read and then stored into the DR from DDRAM or CGRAM by an internal operation.

2.1.2 Busy Flag of LCD

When the busy flag is 1, the HD44780U is in the internal operation mode, and the next instruction will not be accepted. When RS = 0 and R/W = 1 (Table 1), the busy flag is output to DB7. The next instruction must be written after ensuring that the busy flag is 0. The following diagram can visualize the timing diagram for the busy flag check for the LCD.

Checking the Busy Flag (BF) of LCD

2.1.3 Address Counter of LCD

The address counter (AC) assigns addresses to both DDRAM and CGRAM. When an address of an instruction is written into the IR, the address information is sent from the IR to the AC. Selection of either DDRAM or CGRAM is also determined concurrently by the instruction. After writing into (reading from) DDRAM or CGRAM, the AC is automatically incremented by 1 (decremented by 1). The AC contents are then output to DB0 to DB6 when RS = 0 and R/W = 1.

2.2 Initializing by Internal Reset Circuit of LCD

An internal reset circuit automatically initializes the HD44780 when the power is turned on. The following instructions are executed during the initialization. The busy flag (BF) is kept in the busy state until the initialization ends (BF = 1). The busy state lasts for 10 ms after VCC rises to 4.5 V.
1. Display clear
2. Function set:
DL = 1; 8-bit interface data
N = 0; 1-line display
F = 0; 5 ´ 8 dot character font
3. Display on/off control:
D = 0; Display off
C = 0; Cursor off
B = 0; Blinking off
4. Entry mode set:
I/D = 1; Increment by 1
S = 0; No shift

2.3 Pin Configuration

The pin configuration of LCD along with their functionality is shown below
Table 1: Pin Assignments of HD44780

2.4 Instruction Set of LCD
Here is the instruction set summary of HD44780 LCD, also some explanation is provided in the following table.
Table 2: Instruction Set Summary of HD44780

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Control Operate the PLC - part 5

4.2.3.8. Programming PLC with Computers
To program the PLC with a computer requires a supporting software. The supporting software for Omron PLC is Syswin (we will learn is SYSWIN V3.4.), LSS, CX Program and others. For siemen PLC ; Micro Win S7, S5, and others. For Mitsubishi PLC; Melsoft series Dev 7, Médoc, and others. For LG PLC; KGL_Win, GM_Win, and others. Excess programming PLC with a computer is very much, among others; can be done editing programs using ladder diagrams or with mnemonic codes. Can also to upload programs, download programs, monitoring programs, detect errors in the PLC and many other functions. Communication tools used for this purpose is a RS232C serial port.

Syswin Software V3.4 operating instructions.
a. Creating new programs
• Run Syswin 3.4 so that will be raised ladder editing window as shown in Figure 7.1. If observed, sections on the left contains the components or conditions ladder diagrams, summary or summary shown in Figure 7.2. While the top is used for file management (saving, reading, etc.), the management ladder and means of communication with the PLC.

Figure 4.71. Program window Syswin 3.4


Figure 4.72. Brief summary of the key (shortcut)

• click File - New Project - Ok (Enter)

Figure 4.73. New Project

• In the New Project Setup window, select ladder - Select the PLC and CPU type - Ok(enter)

Figure 4.74. Select the PLC and CPU type

• Click the symbol of NO (normaly open) contact - put in front of the cursor - click - give address according to PLC inputs eg 0.00 - OK (enter)

Figure 4.75. Put the input contact symbol

• Click the Output symbols - give the corresponding address for output eg 3.00 - Ok (Enter)

Figure 4.76. Put the output symbol

• To end the program, highlight the latest network - click Block - click on the Insert network - click bellows current network - Ok (enter), and then, click FUN - click select - select All instruction in the group - Select END (01) on the function - Ok - Ok

Figure 4.77. Add network

Figure 4.78. Put the END function

b. Giving Labels And Comments On Network
Label and comment on each network aims to give the title of Project and comments relating to the operations and methode at the network, the way is as follows:
• Highlight and then double-click on Main 1, then label the block1 (example: ON / OFF), write comments relating to the control circuit functions on the network and then click Close.

Figure 4.79. Put label and comment on the network

c. Saving Project at the Drive C
Aim is to store program data that has been made at any time if the program is needed we can call back the program, the way is as follows:
• Highlight at File - highlight at Save project - Ok (enter)

Figure 4.80. Saving Project

• Select Drive C (corresponding to the selected folder) - write file name - Ok (enter)

Figure 4.81. File Naming

d. Removing auxiliary contact of I/O, and Editing Address of I/O In Ladder
d.1. Delete Item or Cut Item in Ladder
Phase should be done to delete or cut the auxiliary contact of I/O is as follows:
• Highlight auxiliary contacts (NO,NC or output) - click on delete symbol (delete items/cut items)

Figure 4.82. Deleting a symbol

d.2. edit the address inputs and outputs (I / O) in Ladder
Phase should be done to edit the address input or output (I / O):
• Highlight in input or output - double click it and then change the address input / output according to what we want.

Figure 4.83. Editing symbols

d.3. Removing / Delete Network on Ladder
Phase should be done is as follows:
• put / click the cursor on the network you want to erase / delete
• click on menu block and then delete network

Figure 4.84. Removing network

e. Insert network
• Highlight on network to be inserted - click on menu block - click insert network - click bellows / above current network - Ok (enter)

Figure 4.85. Insert network

f. Giving Symbol And Comment On Input / Output (I / O)
• Double click on the network that will be a symbol and comment - browse
• Give the symbol and comment on the I / O - store - Ok - Ok

Figure 4.86. Giving symbols and comments on I / O

g. Creating / Viewing program in the form mnemonic code
• highlight network to be created or seen then click Editor - click Statement List Editor - write the mnemonics code in the box instruction - click test to see results in the form of ladder - click close to close.

4.87. Dialog box of Statement List Editor

h. Printing Ladder Diagrams
To print a Ladder Diagram can be done with Ctrl + P so that the displayed Print dialog box in Figure 88. Make settings as shown in Figure 88 (which in cross only Ladder Diagram), then click option that will display the next dialog box as shown in Figure 89. Make settings as shown in the picture 89.

Figure 4.88. Dialog box of Print

Figure 4.89. Dialog box of Ladder Diagram Options

Network separators can be selected:
• Print separators
• Include comments

Print separators can be done by:
• As editor
• Every network or
• Every group

For general settings, can be done:
• Print step numbers in the margin
• Print Statement List
• Print Address List

For Cross reference can be activated or not, by checking in field of Cross Reference with Fully or compactly. For Page Breaks can be activated or not by checking in field of Enable page breaks and can be selected:
• Every network
• Every group or
• Every block

Transfer Program
a. Download Program & Test Running
Download program is to transfer the programs that you have made from your computer to PLC, there are two prerequisites that must be met, namely: Hardware requirements and Software requirements. Hardware requirements are interface from a computer to PLC must be connected, then Software requirement are PLC mode must be on condition OFF / STOP, the way is as follows:
• Select Project menu - Communications, select Port/Com and the appropriate Interface - Click Test on PLC until Status is Connected then Ok (Enter)
• Click Phone icon (sF9) / Communications Connect
• Click Icon of change mode PLC (sF10) on position Stop or Program
• Click Download menu - click Download program to PLC
• To Test Running after transfer - Click on PLC Mode (sF10) - select Run Mode - then Ok

Figure 4.90. Test connection

Advanced Programming Instructions
a. Timer (TIM)
• Click TIM - input the numbers of timer (000 to 511) - input the value of time then click Ok

Figure 4.91. Put Timer

b. Counter (CNT)
• Click CNT - input the numbers of counter (000 to 511) - input the value of count then click Ok

Figure 4.92. Put Counter

c. KEEP, DIFU, DIFD, IL-ILC, Shift Registers, JUMP, ADD, SUB, HIGH SPEED TIMER, Compare, INC, DEC.
• Click FUN - select All Instructions - select function that you want to use then click OK

Figure 4.93. Other advanced instruction

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