Next Generation Guardmaster Safety Relay (GSR) Wiring Diagram
The Advantages of Safety Networking Over Point-To-Point Wiring for Integrating Multiple Safety...
-
Upload
bilal-shahid -
Category
Documents
-
view
214 -
download
0
description
Transcript of The Advantages of Safety Networking Over Point-To-Point Wiring for Integrating Multiple Safety...
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 1/9
The Advantages of Safety Networking over Point-to-Point Wiring for Integrating Multiple SafetyComponents
Making safety a priority when employing tool exchangesystems
By ifm efector
Abstract
Traditionally, pointtopoint wiring has been the standard for wiringsafetyswitching components. Today, a new networking productintegrates safety devices into standard PLCs and other higher levelnetworks and provides a system for plants to operate more efficientlywhile simplifying complex wiring and troubleshooting. This articleexamines how this new networking method compares to traditionalwiring and the advantages of implementing safety networking. Thearticle covers:
The role safety systems play in today’s industrial automationfacilities
The key advantages networking systems offer over pointtopoint wiring
The product breakthrough for safety networking – Safety at
The Advantages of Safety Networking
Machine & Process SafeGuardingArchived ArticlesLibrary
PORTALS:
ProcessAutomation
FactoryAutomation
ManufacturingOperations
IndustrialNetworks Industries
SEARCH
PULSE NEWS PRODUCTS JOBS DIRECTORIES EVENTS LIBRARY
HOME LOGIN SUBSCRIBE
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 2/9
Work, illustrating the system in a conveying application
How technology has influenced the need for integration ofsafety controls
Safety in Industry
In the past, safety standards across the board allowed only for hardwired safety components. Today new approvals such as IEC 615081and revised standards like NFPA 792 (2002 edition) are in place toaccommodate safety networks and provide new standards forprotection of life and limb. These new standards have led to anupsurge of interest in safety networks not only for their improvedsafety functions, but also for the ROI they promise to offer whenimplemented with other networks throughout an industrial enterprise.
With government regulations, consumer demand, and globalcompetition on the rise, companies are forced to utilize the mostcosteffective, efficient means of operating their production facilities.While operational efficiency is a concern for any business,manufacturing and process control systems also require the accurateand reliable transmission of data from sensors and control devices onthe plant floor to processes across the entire manufacturingenterprise. This reliability is most important when the safety ofhuman life is at stake. Safety is and will continue to be a topic firstand foremost for operational engineers and plant managersthroughout the world.
Traditional Wiring
Despite the level of importance safety systems carry, there is aneverpresent difficulty for safety to be cost effective whilemaintaining the high level of reliability and accuracy the systemsrequire. Traditionally, safety systems are constructed using pointtopoint hard wire logic and safety relays that are connected toswitching components and emergency stop buttons located in thefield. Multiple wires from each device, fed through control cabinets,often result in large wire bundles running through the system. Due tothe sheer volume of wires, installation time is considerable andtroubleshooting is complex. Below is a list of the five biggestchallenges plants face when using pointtopoint wiring. While thesemay currently be the norm for safety systems, other industrialcontrol applications are meeting these challenges by moving fromhard wire based controls to industrial networks.
Challenges of conventional pointtopoint wiring
Wiring Hard wiring each safety device to the main controlcabinet can be very costly and time consuming.
Troubleshooting When troubleshooting a safety system,conventional wiring makes it difficult to determine where thepoint of failure has occurred.
Additional Equipment With conventional pointtopoint wiring,additional input cards are needed for device status notification.
Complex disassembly and assembly When shipping andtransporting a safety system, the disassembly and reassemblyof each contact in the system can be very time consuming.
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 3/9
Multiple safety zones Additional relays are required for eachsafety zone
Industrial Networks
Today, there are many different types of industrial networking or‘fieldbus’ technologies on the market. ASi, DeviceNet, Profibus, andEthernet are just some of the systems gaining popularity as plantengineers search for ways to streamline controls within their plant. Inthe past, pointtopoint wiring has limited the information that can betransferred and received from the field. Often times, additionalwiring, input cards, and other compatible equipment is needed toprovide accurate diagnostics and process feedback. This increase incost, as well as the increased level of data transmission, opened thedoor for industrial networks. Industrial networking technologiesoffered the market an industry standard method of connectingdevices together for the transfer of data back to a controller andallowed for more flexible applications and system expansion.Industrial networks use a highspeed communication backbone thatintegrates PCs or workstations with devices in the field to give theoperator a userfriendly interface for communication with each devicelocation in the field.
Safety at Work
As industrial controls make the progression from hardwire basedcontrols to industrial networks, companies have begun to developsafetynetworking systems that function directly with these networks.The most popular of these in the market today is Safety at Work.Developed by a consortium of the world’s foremost experts onindustrial controls, Safety at Work was designed to simplify wiringand overcome the challenges facing safety systems that operate withpointtopoint relay logic.
The Safety at Work system is one of the first fully approved industrialsafety networking systems. It carries TUV approval for application upto control category 4 according to EN95413 and SIL 3 according toIEC 61508. The system uses one twowire flat cable that integratesdirectly with most standard PLCs including Allen Bradley and Siemensas well as most bus systems. The system replaces hard wire logicwith easily configurable draganddrop software by means of a PC.The following illustration shows the basic design of a Safety at Worknetwork compared to the same components wired in a traditionalpointtopoint method. The illustration shows a significant reduction inwires and materials when using Safety at Work.
Figure 3 – PointtoPoint Wiring vs. Safety at Work
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 4/9
Safety at Work is comprised of three main components. (1) A SafetyMonitor resides in the main control cabinet and is responsible for thetranslation of safety messages throughout the network. (2) An ASifieldbus network provides the communication infrastructurethroughout the system. (3) Safety Input modules are used tointerface directly with standard safety switching components andintegrated Safety at Work Estop buttons.
Utilizing the ActuatorSensor interface protocol (ASi) as thebackbone for the transmission of safetyrelated information, 8x4 bitdata sequences are stored in safety modules in the field. Duringinstallation and start up, the safety monitor must learn these codesequences. While in operation the safety monitor constantlycompares the target sequence with the current sequence of the safety
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 5/9
module. If a safety module provides a wrong code sequence (e.g.4x0 bit), the safety monitor switches to the safe state.
The ASi powered Safety at Work system uses a Control PlatformInterface to connect with most standard PLCs and higher levelnetworks. The system has the ability to handle multiple safety zoneson one system and can be configured in almost any topologyincluding ring, star, and trunk and drop.
Why make the move to safety networking?
With new technology supplying plant engineers with products thatcontinually improve the speed and efficiency of their equipment, thesafety liabilities to operate these new technologies are increasing aswell. The safety aspect of the job will only continue to grow asequipment becomes more and more complex. This is why newstandards and approvals have been put in place to insure that safetytechnology grows with the equipment it monitors. The key to thesuccess of any system relies heavily on the system’s seamlessimplementation and simplicity of operation. In manufacturing plantsthroughout the world, the integration of multiple machines andapplications produces the highest quality products in the highestquantities possible. Networks, put in place to achieve this integration,provide better control and monitoring of new and existing equipment.With this technology now available to offer this same control over lifeand limb, it seems only logical that safety networking beimplemented not only to protect the production process but tosafeguard the most important component of any plant – its people.
Footnotes
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 6/9
SUBMIT
SUBSCRIBE
* First Name
* Last Name
* Email Address
* Company Name
* Required Fields
1 IEC 61508 is concerned with functional safety, achieved by safetyrelated systems that are primarily implemented in electrical and/orelectronic and/or programmable electronic (E/E/PE) technologies, i.e.E/E/PE safety related systems.
2 NFPA 79 is the Electrical Standard for Industrial Machinery fromthe National Fire Protection Agency
3 EN9541 categories represent a classification of the safetyrelatedparts of a control system with respect to their ability to withstandfaults and their behavior in the event of faults.
***
This article was written and provided by ifm efector. ifm efector isone of the world's largest manufacturers of sensors and controlproducts for industrial control applications. Products include proximityswitches, photoelectric sensors, fiber optics and controllers, speedmonitors, pressure sensors, flow sensors, temperature sensors, levelsensors, valve position sensors, mobile controls and a complete lineof ASI networking and control products. For more information,Contact ifm efector or visit their website at www.ifmefector.com.
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 7/9
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 8/9
FollowUs {
12/14/2015 The Advantages of Safety Networking over PointtoPoint Wiring for Integrating Multiple Safety Components
http://www.automation.com/library/articleswhitepapers/machineprocesssafeguarding/theadvantagesofsafetynetworking 9/9
MY CART
BooksOnline TrainingMerchandise
SUBSCRIBE
Russian
COMPANY
AboutAdvertiseSubmitContentPost aJobTestimonialsContactUsSitemap
PORTALS
ProcessAutomationFactoryAutomationManufacturingOperationsNetworks &Field BusesIndustries
INDUSTRIES
AutomotiveBuildingAutomationChemicalEmbeddedAutomationFood &BeverageMachine Tools,CNC & DNC
MaterialHandlingOil & GasPackagingPharmaceuticalsPower &Energy(Utilities)Water &Waste Water