Belajar PLC dan SCADA

Just another Blog about Programmable Logic Controller & SCADA.

RS232 to USB converters

Written by Kang Abu on 10:59 AM

Konverter RS232 USBImage via Wikipedia
USB to RS232 conversion
One of the most common questions asked to me in emails is how an RS232 connector can be soldered to an USB cable. Unfortunately life is not that simple. Although RS232 and USB (universal serial bus) are both serial communication standards to connect peripherals to computers, they are totally different in design. A simple cable is not enough to connect RS232 devices to a computer with only USB ports. There are however converter modules and cables that can be successfully used to connect RS232 devices to computers via an USB port. These adapters and cables contain electronics, and the success rate depends on the capabilities of this electronics and the device driver software that is shipped with the converter to communicate with these electronics over the USB bus. Before buying your USB to RS232 converter, it is advised that you read this document first.

Differences from the application point of view

RS232 is a definition for serial communication on a 1:1 base. RS232 defines the interface layer, but not the application layer. To use RS232 in a specific situation, application specific software must be written on devices on both ends of the connecting RS232 cable. The developer is free to define the protocol used to communicate. RS232 ports can be either accessed directly by an application, or via a device driver in the operating system.

USB on the other hand is a bus system which allows more than one peripheral to be connected to a host computer via one USB port. Hubs can be used in the USB chain to extend the cable length and allow for even more devices to connect to the same USB port. The standard not only describes the physical properties of the interface, but also the protocols to be used. Because of the complex USB protocol requirements, communication with USB ports on a computer is always performed via a device driver.

It is easy to see where the problems arise. Developers have lots of freedom where it comes to defining RS232 communications and ports are often directly, or almost directly accessed in the application program. Settings like baudrate, databits, hardware software flow control can often be changed within the application. The USB interface does not give this flexibility. When however an RS232 port is used via an USB to RS232 converter, this flexibility should be present in some way. Therefore to use an RS232 port via an USB port, a second device driver is necesarry which emulates a RS232 UART, but communicates via USB.

Many applications expect a certain timing with RS232 communications. With ports directly fitted in a computer this is most of the time no problem. The application communicates directly, or via a thin device driver layer with the UART, and everything happens within a well defined time frame. The USB bus is however shared by several devices. Communication congestion may be the result of this, and the timeframe in which specific RS232 actions are performed might not be so well defined as in the direct port approach. Also, the double device driver layer with an RS232 driver working on top of the complex USB driver might add extra overhead to the communications, resulting in delays.

Hardware specific problems

RS232 ports which are physically mounted in a computer are often powered by three power sources: +5 Volt for the UART logic, and -12 Volt and +12 Volt for the output drivers. USB however only provides a +5 Volt power source. Some USB to RS232 converters use integrated DC/DC converters to create the appropriate voltage levels for the RS232 signals, but in very cheap implementations, the +5 Volt voltage is directly used to drive the output. This may sound strange, but many RS232 ports recognize a voltage above 2 Volt as a space signal, where a voltage of 0 Volt or less is recognized as a mark signal. This is not according to the original standard, because in the original RS232 standard, all voltages between -3 Volt and +3 Volt result in an undefined signal state. The well known maxim MAX232 series of RS232 driver chips have this non-standard behaviour for example. Although the outputs of these drivers swings between -10 Volt and +10 Volt, the inputs recognize all signals swinging below 0 Volt and above 2 Volt as valid signals.

This non-standard behaviour of RS232 inputs makes it even more difficult to select the right RS232 to USB converter. If you connect and test an RS232 to USB converter over a serial line with another device, it might work with some devices, but not with others. This can particularly become a problem with industrial applications. Low-cost computers are often equipped with cheap RS232 drivers and when you test the RS232 to USB converter with such a computer, it might work. But the same converter may fail if you try it in an industrial environment. The chances that RS232 ports from low-cost computers accept signals in the 0..5 Volt range are higher than with industrial equipment which is often specifically designed to be immune for noise.

Another hardware specific problem arises from handshaking to prevent buffer overflows at the receiver's side. RS232 applications can use two types of handshaking, either with control commands in the data stream, called software flow control, or with physical lines, called hardware flow control. Not all USB to RS232 converters provide these hardware flow control lines. It is not always easily identified if an application needs them. Some applications do not use hardware flow control at all, and those cheap USB to RS232 converters will work without problems. Other applications use hardware flow control, but infrequently. Only with large data bursts, or in situations where the CPU is busy performing other tasks, hardware flow control might kick in to prevent data loss. In those situations, communications may seem error free, but with sometimes bytes lost, or unspecified errors in the communications.

USB to RS232 converter selection criteria
Resuming, when choosing the right USB to RS232 converter, look at the following potential problems:

    * Does your application have very tight timing requirements? In that case it might be better to use an internal RS232 port, instead of an USB to RS232 converter. The extra layer at the device driver level and bus congestion might make the communications less reliable.
    * What are the RS232 output voltages of the converter. Do they meet the requirements for the equipment you want to connect?
    * What are the handshaking requirements for your application? If hardware flow control is required, make sure that these inputs and outputs on the converter are present.
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CX-One Version 4.0: Better Than Ever

Written by Kang Abu on 1:25 PM

Easy and intuitive operation to reduce the work involved in programming.
 


  New Feature 1: Smart Input 

A Smart Input Function greatly reduces the work required to input programs


Steps required to input ladder diagrams, now reduced by 50%, 
compared to CX-Programmer Version 8.
A complete range of intuitive programming functions is provided, including instruction and address input assistance, address incrementing, and address Incremental Copy.
These functions enable waste-free programming with minimal effort.



  New Feature 2: Memory Operation Preview 

Easier Preliminary Verification of Position Control Units


The memory operation data created on the CX-Programmer for CJ1W-NC[][]4 Position Control Units can be used to display graphs and motion paths for the position or speed operations of each axis. This enables smoother startup and reduces the work required for preliminary system verification.
Connection Diagram on Memory Operation Preview

*This function will be supported for EtherCAT-compatible Position Control Unit in the near future.


  New Feature 3: Easier Network Link Setting 

Easier Setting of Tag Data Links for EtherNet/IP


Just drag and drop on the network configuration display of the Network Configurator to create tag data links for EtherNet/IP networks.
Easier Setting of Tag Data Links for EtherNet/IP


  New Feature 4: Reusable Designs 


Easily Reuse Legacy Programs

Data Structures:
In addition to arrays, which can be used to manage data with the same data type, data structures can be used to manage data with different data types in the same structure. And the data structures are managed using names and data types rather than I/O memory addresses. Using data structures enables building legacy programs for data processing that can be easily reused.
Easier data management

Timer and Counter Data Types:
Timer and counter data types can now be treated as symbols.
You can thus use them as symbols in arrays to build legacy programs that can be easily reused.
Reuse timer/counter data types



  Support for More Hardware Products 

Support for the SYSMAC CJ2M (coming soon)

Windows7 is now supported!
 

The following units are also be supported.



  • CP1E-NA20 CPU Units (20 points)



  • Compact NV-series NV4W Programmable Terminals



  • CJ1W-AD042/DA042V Analog I/O Units (high-speed models with direct conversion)



  • CJ1W-SCU22/SCU32/SCU42 Serial Communications Units (high-speed models)
The following Units will be supported in the near future.



  • CP1E-E10/E14/N14/N60 (10/14/14/60 points) (coming soon)



  • CJ1W-NC281/NC481/NC881 EtherCAT-compatible Position Control Units (coming soon)

Features

Position Control


Communications Setup Integrated into the CX-Programmer (coming soon)
Applicable Models: CJ1W-NC[]81


Set Up the Position Control Units and Servo Drives from One Connection

Just connect the computer to a CPU Unit port to set up the EtherCAT-compatible Position Control Units and EtherCAT communications.

You can also directly start the CX-Drive Support Software to set the Servo Drives connected to the Position Control Units.


Set 
Up the Position Control Units and Servo Drives from One Connection 



 

 

Network


Applicable Models: CJ2

Easy connection with USB

A standard USB cable can be easily connected to the USB port on the front of the CPU Unit.

Easy
 connection with USB

 

Easy Connection with EtherNet/IP

Easy connection by specifying the computer LAN (Ethernet) port and IP address only.
 
Easy
 Connection with EtherNet/IP
* CJ2 (built-in EtherNet/IP) CPU Units only.

 

Prevent Connection Errors by Verifying PLC Names

The CJ2 CPU Unit can record a PLC name. Errors in transfers can be prevented ahead of time because the PLC name can be compared with what is in the project file when connecting online.

Prevent Connection Errors by Verifying PLC Names
 

Easy Setting of Tag Data Links for EtherNet/IP


In addition to creating data links with the EtherNet/IP Datalink Tool using I/O memory addresses, you can also use network symbols for tags to easily create the data links.

With EtherNet/IP, high-speed, high-volume data links can be created with different cycle specifications for each applications, regardless of the number of nodes.

*CJ2 (built-in EtherNet/IP) CPU Units only.

Now 
Supports EtherNet/IP and CompoNet
 

 


Debugging


Time Required for Onsite Startup and Debugging Has Been Significantly Reduced

With CX-One version 4.0, debugging is efficient with simultaneously monitoring and management of multiple networks and PLCs.


Management of Multiple Networks


The operation of networks with configurations consisting of multiple networks including PLC networks such as EtherNet/IP and Controller Link, field networks such as DeviceNet and CompoNet, and networks for Programmable Terminals and Serial Devices, can be restored simultaneously from the CX-One.

Onsite start up and debugging can be conducted efficiently and without errors because PLCs and devices can be selected from the window to transfer programs and parameter data to the computer during operation.

Using CX-Integrator


Ladder Diagram Monitoring for Multiple PLCs

Multiple PLCs can be monitored by displaying them in series on the screen. This way it is easy to debug data links between PLCs and monitor the inputs and outputs of different PLCs.

Using CX-Programmer
 


Screen Designing using CX-Designer / NV-Designer


The CX-Designer Simplifies the Processes from Screen Design to Debugging for the NS-series Programmable Terminals


The time required for designing can be significantly reduced because of the compatibility with SYSMAC CJ-series PLCs. The process of designing screens is easier with expanded functionality.

Applicable Units: NS Series, NSJ Series


Communications Components and the Smart Active Parts (SAP) Library Significantly Reduces the Time Required to Create Ladder Diagrams and Screens


There are over 3,000 Smart Active Parts that can directly access OMRON PLCs and components. Simply select and paste a part from the SAP library onto the screen. Detailed screens and ladder diagrams do not need to be created.

Immediate creation of Temperature Controller Settings and Monitor 
Screens


Using Software Components, Error Checking and Parameter Setting Can Be Done without a Computer


There are many software components in the Software Function SAP Library that can be easily incorporated into the NS-series Programmable Terminals.

Simply select and paste software components on the screen. Device errors can be checked and parameters set without a computer.

Easy
 Tool (Software Function SAP Library)

Use the NV-Designer to Easily and Quickly Design Screens for the NV Series of Compact PTs


Applicable Units: NV Series
NV 
Series with NV-Designer
 



Servomotor Control using CX-Motion-NCF & CX-Motion-MCH


The CX-Motion Supports Motion Network Servo Systems


Improve productivity of motion network servo systems using MECHATROLINK-II for design, startup, and maintenance.


Easy Management of Parameters While Still Connected to PLCs

CX-Motion-NCF


Settings can be modified while connected --> Wiring can be 
checked while connected. Operation can be checked while connected.

 

Even Easier to Start Up a System

CX-Motion-MCH


Programming is easy --> Debugging programs is easy --> 
Checking operation is easy.
 


Control of Temperature Controller using CX-Thermo & CX-Process Tool

 

The CX-Thermo/CX-Process Software Supports High-level Temperature Control.


Setting Temperature Controller Parameters Is Easier

CX-Thermo

Parameters can be easily set from a list:
Work
 space, parameter property window, output window, parameter list.



  • Easy Parameter Settings

    Parameters can be set even for Temperature Controllers that do not support communications.
    Parameters can be saved, and then copied, or reused and edited (Parameters can be exported in CSV or HTML format.)
     



  • Displays Only What Is Used

    To avoid unintentional use of parameters, unused parameters can be masked (i.e., hidden)
Applicable Units:
E5CN/E5CN-H/E5AN/E5AN-H/E5EN/E5EN-H, EJ1, E5ZN, E5AR/E5AR-T/E5ER/E5ER-T
*The DeviceNet type is excluded


Programming for the Process Controller Is Easier

CX-Process Tool
 

Control Programs can be constructed by pasting function blocks:

Project workspace, content check (block diagram, etc), output 
window



  • Control Can Be Customized

    Control programs can be constructed by pasting function blocks and connecting them. They can be used for simple PID control, program control, and cascade control.
     



  • Easy Creation of an HMI

    Screens for the NS-series PTs (NS runtime screen) are automatically generated from the function block programs. Standard control screens and tuning screens do not need to be created manually.
Applicable Units:
CJ1G-CPU4[]P/CPU4[]P-GTC, CS1W-LCB01/LCB05/LCB05-GTC, CS1W-LC001, CS1D-CPU6[]P

Wonderware InBatch Software

Written by Kang Abu on 2:14 PM

WonderwareLogoImage via Wikipedia
InBatch is powerful software that can be used in the most complex batching processes that require a high level of flexibility. Consistent with the ISA S88 flexible batching standard, InBatch software offers comprehensive batch execution and equipment history, material genealogy, stringent security, Web-based reporting and the ability to facilitate the design and implementation of systems that are compliant with FDA 21 CFR Part 11 regulations.

Wonderware InBatch continues the success of I/A Series Batch, InBatch for InFusion and Wonderware InBatch into a single software release and provides integration with Wonderware System Platform and Invensys InFusion Enterprise Control System.
 
 
 
 

Key Benefits

  • Reduce life-cycle costs of batch execution systems
  • Optimized throughput and maximized equipment utilization
  • High flexibility in recipe procedure- and material formulation changes
  • Enhanced batch application capabilities with ArchestrA platform integration, enabling end to end genealogy

Key Capabilities

  • Powerful recipe management and batch execution
  • Multiple batches executed simultaneous, also on shared equipment
  • Redundant Batch Server option
  • Comprehensive electronic batch record (EBR) and reporting capabilities out of the box
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GPS + Smartcard Alat Pembayaran Tol di Korea Selatan

Written by Kang Abu on 11:06 AM

Loads of GPS devices in our carImage by mroach via Flickr
Wah ini bahasan kayanya menarik nih,… Selama pengalaman traveling di negara Korea Selatan ada beberapa alat yang dipasang di mobil sebagai alat navigasi bagi driver dan Smart Card untuk Tol.
Ini dia photonya sempat aku jepretttt….
1. GPS.
dsc04566_cmprs.JPG GPS singkatan dari Global Position Systems. Di negara-negara maju termasuk Korsel salah satunya GPS merupakan barang yang biasa anda jumpai di mobil-mobil pribadi atau taxi.
Check di sini untuk penjelasan detail mengenai GPS, Klik aja disini!
Fungsi sebagai alat navigasi bagi pengendara. Jika anda akan menuju suatu kota anda tinggal mencari kota tujuannya. Secara otomatis alat ini akan menuntun anda hingga ke tujuan. Hebatnya keakurasiaan GPS di korea ini bisa dibuktikan.
Ada satu pengalaman selama perjalanan, teman saya (driver yg baik, hehehe) gak tahu alamat teman yang akan di kunjunginya. Tetapi dia tahu no telp temannya itu. Dengan cepatnya dia menuju ke monitor GPS yang taouchscreen itu memasukan No. Telp rumah temannya itu… tak lama kemudian GPS tersebut langsung menunjukannya dan menuntun kita ke tempat tujuan.
dsc04565_cmprs.JPGSelama perjalanan panjang dari Icheon airport ke tempat tujuan kerjaku di kota kecil Geochang. Kita melalui jalan high way. Kira-kira setiap 3km atau 5km di jalan tol dipasang kamera control speed. Kamera tersebut berfungsi memantau kecepatan kendaraan yang melaju di jalan tol. Pengemudi mobil hendaknya tahu bahwa di jalan tol maximum kecepatan yang diperbolehkan 100km/jam. Tetapi kadang-kadang atau seringnya pengemudi melebihi batas kecepatan yang ditentukan.
Nah… dengan bantuan GPS secara langsung GPS akan memberi tahu bahwa 500m di depan kita ada kamera pemantau kecepatan. Jika kita melebihi batas kecepatan yang ditentukan GPS itu langsung memberi tahu dengan suara manusia…. ya bisa di ibaratkan ngomongnya gini “Mas-mas kurangi kecepatannya ada kamera di depan”…. hehehe… kira-kira begitu bunyi yang keluar dari GPS (red:.karena gue kagak ngarti bahasa korea… maklum). Jadinya si pengemudi aman deh.. gak kena sama pak Polisi, karena setiap melewati maksimum pasti GPSnya ngomong….
Hebatnya lagi GPS tersebut dilengkapi dengan TV, MP3 Player, Video Player (Multimedia). Trus suaranya bisa di sadap di radio FM mabil karena ada tunnernya. Pokoknya keren abis deh..
Trus.. untuk map yang ada di dalam GPS tersebut setiap hari ada update, untuk memperbaharui jika ada jalan atau gedung baru yang ada di seluruh korea selatan. Anda tinggal menuju situs provider di internet dan download deh….. Jadinya informasi yang ada di GPS jadi akurat dari hari ke hari…..
Boleh coba.
2. Smartcard untuk Tol
dsc04567_cmprs.JPGNah yang satu ini juga lumayan keren. Smartcard ini berfungsi sebagai alat pembayaran di tol. Jika kita melewati gerbang tol gak usah anti ngambil tiket dan bayar. Tapi secara otomatis uang yang ada didalam smartcard tersebut akan di debet. Kita sebagai pengemudi pada saat melewati gerbang tol ada satu display yang menunjukan berapa saldo yang ada di smartcard kita.
Prinsipnya sama dengan voucher HP. Kalau abis ya harus di isi ulang.
Dengan alat ini kemacetan bisa di hindari. Pemanfaatan teknologi canggih saat ini di negara-negara yang bisa dikatakan maju sudah menjadi barang yang biasa.
Kapan di Indonesia teknologi ini mulai diterapkan ya?
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Free Bulletin from YOKOGAWA

Written by Kang Abu on 12:31 PM

Industries

Download printer-friendly version [PDF] , Right Click and SAVE AS....
Viewing PDF files requires Adobe Acrobat Reader.
Download printer-friendly version [PDF]
Viewing PDF files requires Adobe Acrobat Reader.
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Yokogawa Releases FAST/TOOLS R9.03 SCADA System

Written by Kang Abu on 12:20 PM

Yokogawa logoImage via Wikipedia
Yokogawa Electric Corporation announces the release of version R9.03 of the FAST/TOOLS web-based SCADA system. Adopted by many innovative industrial automation users worldwide, this platform-independent process management software sets the standard for Operational Excellence. Combining the latest web technology with exceptional quality has resulted in the most advanced SCADA solution yet – one that is designed to meet the latest engineering and maintenance requirements. Thirty years of project experience and innovation in the oil & gas, petrochemical, and power industries are the foundation for this next generation SCADA software.
This greatly enhanced version of the FAST/TOOLS web-based SCADA system enables a new and innovative approach to remote engineering and maintenance, deploying process applications and monitoring via web-based services. Its use of the latest technologies and web-based architecture provides management and maintenance personnel easy and secure access to their assets FAST/TOOLS has high-level system integration capabilities, facilitating ever more intuitive and advanced system deployment and significantly reducing costs.

Main Features


Web-based maintenance, engineering, and application deployment
Remote asset management drives down operating costs and optimizes the sharing and exchange of information. The latest web technologies are incorporated in the Java-based FAST/TOOLS engineering and maintenance environment to enable access and execution within standard web browsers like Internet Explorer and Firefox. This facilitates access by the various start-up and design teams to the application and system software configuration, in a zero deployment and transparent manner. The integrity and confidentiality of process information is preserved. Java was chosen as it can be used with standard web browsers; it is architecturally neutral and provides good support for superb graphics.
Numerous benefits are derived from this concept including global access and sharing of data via collaboration centers and other venues, allowing continuous application development and management to take place. Furthermore, a reduction in the number of required paper documents and the higher level of management efficiency made possible by the continuous availability of process information are expected to lead to a reduction in cycle time.
Secure deployment
A commitment to security policies that are in accordance with corporate IT directives is the foundation for our development activities that are targeted at achieving a secure deployment. To enhance security, this system and its applications are hardened to prevent failures and protect against unauthorized access and use. At the same time, thanks to a simple licensing policy, it is now easier than ever to reduce costs through web-based engineering and virtualization. A web-based server and client architecture ensures easy remote access and facilitates the deployment of security enhancements as well as graphics and application services.
Advanced engineering methods
The new engineering and visualization editor with an advanced sheet- and form-based environment allows for a conveniently arranged framework that tremendously reduces the amount of work required for engineering and visualization. The new and easy to work with environment combines the power of today's most sophisticated graphical applications in one easy to manage package. Dynamic layers and visibility groups enable multilevel processes and KPI monitoring and supervision within a single operations architecture.
Multi-language support
The new operator environment is language independent and can be triggered by login procedures and the like. This allows for a mix of local and remote operators, as appropriate, and is not limited by language barriers.
Integration capabilities
A comprehensive new plug-in structure that goes beyond “traditional driver configuration” allows for excellent integration of new and existing infrastructure, guaranteeing seamless vertical and horizontal integration. Capabilities such as soft-marshalling and the integration of FOUNDATION™ fieldbus device messages and information are setting the standard for Operational Excellence. This is both applicable for the Yokogawa product family as well as an extensive list of third-party hardware and software products. These include the Exaquantum Plant Information Management System, the STARDOM Network-based Control System, the DAQMASTER Data Acquisition Unit, the FA-M3 PLC, and the ProSafe-RS Safety Instrumented System.
Windows 7 and platform independence
A variety of software platforms are supported to protect application investments and give users a full choice of hardware and software platforms. The client/host architecture operates securely on the Windows 7, Vista, XP, 2003/2008 Server, UNIX, and Linux Redhat platforms.
Teruyoshi Minaki, a Yokogawa Director and Executive Vice President who heads the Industrial Automation Business Headquarters, comments as follows: "The FAST/TOOLS R9.03 web-based visualization, engineering, and remote maintenance environment brings revolutionary changes to real-time process information intelligence. It's enabling an evolution to a much more intuitive and advanced approach in remote process management and maintenance, and is easy to deploy across the web."

Main Target Markets and Applications

Process monitoring and asset management in industries such as oil and gas, petrochemicals, chemicals, power, pulp and paper, pharmaceuticals, food, iron and steel, waste, and water and wastewater treatment

Yokogawa's Commitment to This Field

Since 1978, Yokogawa has sold more than 10,000 FAST/TOOLS packages worldwide for use in all types of SCADA and process management projects. Yokogawa continually endeavors to meet its customers' needs by providing highly reliable enhancements to this product based on leading edge technology.
For more information about FAST/TOOLS, please visit

About Yokogawa

Yokogawa's global network of 25 manufacturing facilities and 80 companies spans 54 countries. Since its founding in 1915, the US$3 billion company has been engaged in cutting-edge research and innovation, securing more than 7,200 patents and registrations, including the world's first digital sensors for flow and pressure measurement. Industrial automation and control, test and measurement, information systems and industry support are the core businesses of Yokogawa. For more information about Yokogawa, please visit our web site at www.yokogawa.com
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Barcodes

Written by Kang Abu on 12:11 PM

You don’t need to be a rocket scientist to understand them; they are just a different way of encoding numbers and letters by using a combination of bars and spaces of varying widths. Think of them as another way of writing since they replace key-data entry as a method of gathering data. In business, the correct use of bar codes can reduce inefficiencies and improve a company’s productivity thereby growing their bottom line.  Optical Barcode Scanners

Simply put, barcodes are a fast, easy, and accurate way of entering data.

This may come as a surprise to you! A barcode doesn’t contain descriptive data. Just as your social security number doesn’t contain your name or address, a bar code is also a reference number that a computer uses to look up an associated record that contains descriptive data and other important information. 

Barcode Reading


Bar codes are read by sweeping a small spot of light across the printed bar code symbol. Your eyes only see a thin red line emitted from the laser scanner. But what’s happening is that the scanner’s light source is being absorbed by the dark bars and reflected by the light spaces. A device in the scanner takes the reflected light and converts it into an electrical signal.

The scanner’s laser (light source) starts to read the bar code at a white space (the quiet zone) before the first bar and continues passing by the last bar, ending in the white space which follows it. Because a bar code cannot be read if the sweep wanders outside the symbol area, bar heights are chosen to make it easy to keep the sweep within the bar code area. The longer the information to be coded, the longer the bar code needed. And as the length increases, so does the height of the bars and spaces to be read.

Barcode Scanners


There are three basic types of bar code scanners—fixed, portable batch, and portable wireless.

Fixed scanners (hand held or mounted) remain attached to their host computer or terminal, and transmit one data item at a time as the bar code is scanned.

Portable batch scanners are battery operated and store data in memory for later batch transfer to a host computer.

Wireless portable scanners also store data in memory, however data is transmitted to the host in real time. This allows for instant access to all data for management decisions. HHP Dolphin 9500 scanning pallettes

Barcode Symbologies


Bar codes come in many flavors. Most of us are familiar with the ones seen in grocery or retail stores, but there are many others that are used as standards in various industries. Healthcare, manufacturing, retail, etc. all have symbologies unique to their industry and aren’t interchangeable. Why are there so many different types of bar codes? Simply because different symbologies evolved to solve specific problems. Let’s take a quick look at a few of the most common symbologies*, and how, where, and why they’re used:

UPC/EAN - This is the symbol used on items destined for the check-out line. UPC symbols are fixed length, are mandatory in the retail and food industry, and not used anywhere else for the most part. They were developed to meet the needs of grocery retailing as it fits 12 digits into a reasonably compact space.



Code 39 - Developed because some industries needed to encode the alphabet as well as numbers into a bar code, Code 39 is by far the most popular bar code symbology of choice. It is typically the non-food standard bar code, and is used for ID, inventory, and tracking purposes in various industries such as manufacturing. However, Code 39 produces relatively long bar codes and may not be suitable if label length is a consideration.

Code 128 - This bar code came about when the need for a wider selection of characters arose than Code 39 could provide. When label length is a consideration, Code 128 is a good alternative because it’s very compact and results in a dense symbol. This symbology is often used in the shipping industry where label size is an issue.

Interleaved 2 of 5 - Another popular symbology in the shipping industry, Interleaved 2 of 5 is widely used by the warehousing industry, too. This is also a very compact symbology and you’ll see them on the corrugated boxes in which things are shipped to the grocery store.


Postnet - Unique to the United States Postal Service, this symbology encodes zip codes for processing mail for speedy delivery.

PDF417 - Known as a 2D (two-dimensional) bar code, this is a high-density, non-linear symbology that reminds you of a crossword puzzle. But the difference between this and the other bar codes listed above is that PDF417 is really a portable data file (PDF) as opposed to simply being a reference number. Some states require a 2D bar code be printed your driver’s license. If your state has this requirement, it’s interesting to know that there’s room enough in this bar code to encode your name, photo and summary of your driving record, and other pertinent information. As a matter of fact, a PDF417 bar code can encode the Gettysburg Address in a space the size of a postage stamp!

An important fact to remember is that the larger the width of the bars and spaces, the more space it takes to print the bar code; therefore, the lower the bar code density. The thinner the bars and spaces, the less space is required and the higher the bar code density.

To the left, you'll see pictured Banner Engineering's new line of Optical Bar Code Readers.  Capable of reading normal bar code labels as well as 2D labels (at any angle), these readers are state of the art in quality and bare special mention here because they significantly lower the price to quality ratio.

Barcode Scanners


A basic bar code scanner consists of a scanner, a decoder, and a cable that interfaces between the decoder to the computer or terminal. The scanner’s function is to scan the bar code symbol and provide an electrical output to the computer that corresponds to the bars and spaces of the bar code. However, it’s the decoder that recognizes the barcode symbology, analyzes the content of the bar code scanned, and transmits that data to the computer in a traditional data format. A scanner can either have the decoder built into its handle or be “un-decoded” which requires a separate box, called an interface or wedge. Un-decoded scanners are also used when connecting to portable batch terminals as the decoding is performed by the terminal itself.

Fixed Scanners

bulletKeyboard Wedge Readers.  A keyboard wedge reader is attached to a computer through a port called the keyboard interface. When a bar code is scanned, the information is transmitted as though it were keyed in from the keyboard. Sometimes they’re referred to as wedge readers because they physically wedge between the keyboard and the computer and attach as a second keyboard. One great advantage of a keyboard wedge is that bar code reading can be added with no software changes necessary; the software thinks that the data received was entered by a speedy typist. With a wedge reader, any program that accepts keyed data will accept bar code data with no change.
bulletSerial Bar Code Scanners.  Another way to transmit data from a bar code reader to a computer is to connect it to the computer’s RS-232 serial port. The bar code information read will be transmitted in ASCII format and look just like keyed data to the computer. Using a serial port connection is ideal for a multi-user computer. With serial ASCII terminals for each user, the bar code reader can attach between the terminal and host computer and transmit ASCII data just like the terminal.  To the left, see pictured a barcode print and apply application.  The barcode is printed, then verified by a reader, then the pallet is rotated and the same barcode is printed and read on the other side.

Portable Batch Barcode Scanners


Portable batch scanners are hand-held battery operated readers which store data in memory for uploading to the host at a different time. A portable batch reader contains a bar code scanner, an LCD-display to prompt the user to perform a task, and a keyboard to enter variable data such as quantities. A cradle must also be purchased to upload information to the computer. Portable batch scanners are ideal when mobility is a must and when collected data isn’t immediately needed. These scanners come in a variety of styles including hand-held, wearable and truck mounted. Your application will determine which style is best.

Wireless Portable Barcode Scanners


When you need to collect information at a remote location, and need the information immediately, a wireless solution is the perfect one. A wireless scanner is also built into a terminal, and uploads data to the host as it’s scanned, instantly and accurately. Wireless products let the user scan the information at the point of activity which makes it ideal for many industries.

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