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WHY Wireless Wire

WHY Wireless Wire. DRAFT. David J. Southern, P.E. Manager Control Microsystems, Inc. 90 Madison Street, Suite 600 Denver, CO 80206. We don’t like WIRE…………. Wire is expensive to purchase Wire is expensive to install Wire gets stolen Wire gets dug through Wire can be unsafe

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WHY Wireless Wire

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  1. WHY Wireless Wire DRAFT David J. Southern, P.E. Manager Control Microsystems, Inc. 90 Madison Street, Suite 600 Denver, CO 80206

  2. We don’t like WIRE…………. • Wire is expensive to purchase • Wire is expensive to install • Wire gets stolen • Wire gets dug through • Wire can be unsafe • Wire needs protection DRAFT

  3. Wire is BAD…………. • Wire is bad for the environment • Wire takes up room • Wire gets sabotaged • Wire is restrictive • Wire requires maintenance • Wire Kills DRAFT

  4. Rising costs in a questionable economy………? Wireless can be a hedge

  5. Wire sometimes disappears ………… Ripped from the headlines!

  6. In some parts of the United States there is a Shortage of Electricians Wireless can be a hedge

  7. Cut the cord and go wireless………………….. WIRE

  8. Introductory Observations: Information in this presentation are based on IWS use in basic industrial market segments and differentiate from consumer, commercial and light industrial markets. Regardless of how you may interpret information in this presentation, the presenter fully supports the industry need for an effective standard for IWS use in the process world and, along with others, was proactive in launching the SP50X initiative which quickly evolved into the SP100 Standard activity. Overview of Wireless Instrumentation

  9. Wireless based technology: in use since 1941 A new wireless platform implementation emerged in the past few years, -Wireless Sensor Networks (WSN)-based on Local and Personal Area Network topologies which employ Wireless Instrumentation. Industry acceptance of this approach progressed with efforts launching of a number of Wireless Standards development efforts, e.g. SP100, Wireless HART, Key Questions: What currently unmet user need will industrial wireless sensor implementations resolve? How can the users realize the currently available benefits of industrial wireless implementations without undue risk of future obsolescence? Note: For this discussion, a Wireless Instrument is defined as: “ an instrument with sensor/transducer and power supply housed and sold together with wireless transceiver circuitry and antenna”. Overview of Wireless Instrumentation

  10. In a study entitled “Industrial Wireless Technology for the 21st Century” on page 1, US Department of Energy concluded “Wireless sensors could improve industrial production* efficiency by 10% and reduce emissions by more than 25%” In early 2005, at the ARC Automation Conference, analyst Harry Forbes made the following observations*: WSN (wireless sensor networks) are one of the few technologies that offer the prospect for double digit performance improvements This improvement is driven by the drastically lower investment required to implement WSNs relative to wired alternatives Inherent in this concept is the ability of automation applications to extend their reach beyond the constraints of a wired infrastructure *ARCweb Performance Driven Manufacturing – Jan 31 to Feb 2, 2005 Initial Driver for WSN

  11. Identified benefits realized from wireless implementation include: Significantly lower installation cost than wired approaches Low maintenance costs Ease of implementation Battery Powered, “Tether Free”, Deploy “At Will” Enhanced safety through elimination of manual inspections in hazardous locations. Productivity improvement Enhancement to process knowledge base i.e. additional points of measurement data Benefits being achieved by Current Users of Industrial Wireless Sensor Solutions

  12. Benefits being achieved by Current Users of Industrial Wireless Sensor Solutions Results: Industry experience, from over 2000 currently operating networks supporting 25,000 plus WSN’s has shown that total installed cost savings (including the sensor) can be greater than 90% compared to wired solutions. All applications were previously unmonitored points with the exception of replacing poorly performing wired applications, e.g. rotating equipment, “electrically noisy environments, etc. Installation times measured in hours rather than weeks are routinely being achieved. User benefits as measured by ROI are realized in weeks rather than months or years.

  13. Objective: Improve Personnel Safety Application: Safety Shower Monitoring • Safety policy requires alarm indication when safety showers are activated • A single field unit detects eyewash and/or deluge activation through proximity switch closure • The implementation must be capable of deterministic performance, i.e. immediate notification (~1 second) of activation of the shower AND validation that the node is fully operational (also on a ~1 second basis)‏

  14. Refinery: 3 year study 19 Relief and Shut-off valves Yearly Savings: 11,000,000 pounds of process gas Benefits Reduced emissions Lower maintenance cost Longer inspection intervals ROI $1,500,000 per year benefit Wireless investment $38,000 Objective: Enhance Environmental Compliance & Lower Support Cost Application: Relief & Shut-Off Valve Monitoring

  15. Objective: Personnel Safety Hazard Elimination Application: Equipment Monitoring in Confined Space • Large utility tunnel with steam and gas transmission piping • Confined space presents safety hazards for inspections • Existing RTU for gas metering • Steam trap monitors installed with base radio output to RTU • Benefit: Elimination of manual inspection and safety hazard and improvements in preventative maintenance program.

  16. Problem Kiln rotates at 1/2 RPM Skin temperature up to 2300⁰F Solution Special TC and well with heat barrier connected to wireless temperature field unit Direct measurement of internal temperature enables efficiency improvement in harsh environment User quote "The wireless transmitter we installed is working just great… The receiver is getting a signal from the transmitter for the full revolution of the kiln. We are not having any trouble at all with the spikes that we were having before. The control loop we run on that temperature has seen a definite increase in runtime" Objective: Increase Process Productivity Application: Rotating Kiln Control Loop

  17. Prevent overfill at refinery tank farm Cost to install and wire high level alarms over $500,000 Mechanical level switch with field units installed cost under $50,000 Installation time < 1 hour per tank Objective: Improve Environmental Compliance & Safety Application: Level Alarm Monitoring

  18. The 80/20 Rule • Existing Rule • Only 20% of what should be measured in process industries actually is. • Wired installations provide 20% of the data ideally needed to optimally control a process. • New Rule • Now 80% potential of additional measurements allows for: • Better process performance/control • Condition Monitoring • Additional Points for Maintenance • Process Diagnostics • An industrial strength WSN platform can deliver much of the other 80% with low cost, simple installation and nearly zero maintenance. WSN platforms will enhance and extend, not displace, conventional instrumentation usage. • Industrial measurement can be fast, inexpensive and flexible – The New 80/20 Rule

  19. When properly applied, WSN based approaches produce anticipated results, however this experience is not being uniformly realized in the process industry. Various user surveys* have been performed over the past 18-24 months to address this area. Respondents include those that have used Wireless approaches as well as those that have no experience with wireless implementations. Some of the most significant findings include: Respondents do not feel they are very knowledgeable about current wireless technology They are concerned with security and reliability and cost (??)‏ Some have a perception (experience?) of unacceptable performance A significant percentage of respondents believe there are a large number of currently un-served applications that can be served by wireless based technologies Industry Concerns and Questions * Sources include Venture Development Corp., OnWorld, ISA SP100 End-User Survey by Mann Consulting

  20. Wireless Implementation Preference % User Preference 802.11 WiFi (a/b/g)‏ 21 Proprietary Solutions 11 RFID 4 Satellite 3 Cellular 2 Zigbee 2 802.16 WiMax 1 Don’t Know 47 Don’t Care (?)‏ 9 First Concern: User Lack of “Wireless” Knowledge • Clear illustration of confusion. Best Practice #1: Start with the definition of the application requirements. Do not presume the selection of the implementation platform- “one size does not fit all”. Chart Source: ISA SP-100 End-User Survey, Mann Consulting, Inc.

  21. Safety Class 0 : Emergency action (always critical)‏ Control Class 1: Closed loop regulatory control (often critical)‏ Class 2: Closed loop supervisory control (usually non-critical)‏ Class 3: Open loop control (human in the loop)‏ NOTE: Batch levels* 3 & 4 could be class 2, class 1 or even class 0, depending on function *Batch levels as defined by ISA S88; where L3 = "unit" and L4 = "process cell" Monitoring Class 4: Flagging • Short-term operational consequence (e.g., event-based maintenance)‏ Class 5: Logging & downloading/uploading No immediate operational consequence (e.g., history collection, SOE, preventive maintenance)‏ Initial Step in Defining Application Needs Specify Usage Class of WSN’s Importance ofmessage timeliness increases Source: ISA SP-100 WG.

  22. Preparation of an application requirement with prioritization of requirement importance will lead the user to the identification of the preferred implementation approach. Parameters should include - frequency of data measurement - is there a need for deterministic data communication - maximum latency allowed - physical range of transmission - number of measurement nodes - power source specification Consideration of the above can lead to significantly different network selection that is not immediately apparent from a simple application description. Best Practice #2: Ensure that the application requirement is sufficiently detailed to lead to the identification of the most effective WSN implementation. Resolving the Concern: Insufficient Knowledge

  23. WSN security concerns can be segmented into three areas of sensitivity interfering or preventing data transmission data spoofing illegal entry into other secure systems These concerns can be reduced or eliminated by the following use Frequency Hopping Spread Spectrum (FHSS) based protocols to provide agile communication security use a deterministic communication protocol provide secure attachment procedures, error checking and encryption avoid the use of an IP address to the extent possible reduce the node radiated power to limit the range of transmission Best Practice #3: Ensure that all WSN devices have proper security features embedded in the operating system. Resolving the Concern: Security

  24. A first step is to ensure that all WSN devices have received the appropriate agency certifications – FM, ATEX, UL, etc. Secondly, the performance of a Site Validation needs to be mandatory and should identify the presence of any interfering signal as well as ensure that the required link margin for transmitted signal strength will be met. If other wireless systems are in operation at the site a determination of coexistence problems should be performed as part of the site survey. Best Practice #4: Ensure that reliability issues are properly evaluated prior to physical installation of the WSN. Resolving the Concern: Reliability

  25. Wireless Coexistence • Definition • The ability of one system to perform a task in a given shared environment where other systems have an ability to perform their tasks and may or may not be using the same set of rules. From IEEE 802.19 • Facts • 100% Coexistence isn’t always achievable • The environment will continuously change • Neighbors • How do we affect others (Good Neighbor)‏ • How they affect us (Tolerant Neighbor)‏ • Disruption (The Bully)

  26. Wireless Coexistence • The Hazard – The Bully • High energy density transmission • Low data rate – long time on the air • Long data packets • High duty cycle • Still legal under FCC, RTTE rules • The Good Neighbor • Short transmission time • Reduce radiated power • Spread energy (DSSS, Chirp, etc….)‏ • CSMA • Reduced duty cycle • Channel avoidance • Economical use of packets • The Tolerant Neighbor • Frequency hopping • Channel avoidance • Receiver with high selectivity • Error correction • Modulation Techniques • Protocol tolerant to missing packets • Accept interference

  27. Reliability, Security & Coexistence FHSS, Small packet size, high RF energy per bit, Robust Error Detection Good Network Design & Diagnostics Understand and Know link margin Perform a Site Survey to determine presence of interfering signals as well as satisfaction of link margin requirements Eliminate IP addresses as possible. If IP is required insist on high data encryption. Lower the transmitter power, if it cannot be heard, it cannot be hacked FHSS rather than DSSS. Interoperability Wired approaches need to interoperate under SP100, wireless approaches need to coexist and have high survivability under IEEE 802.19. Lack of User Familiarity Access vendor supplied training Use Organization (ISA, IEEE, WINA ) developed guidelines (leading to eventual standards). Summary: Addressing Current Concerns

  28. A Vision For Industrial Wireless Sensors Initially focused on the last 2500 feet to the process point that is not currently attached to the automation platform. WSN’s are here today! WSN’s are available now, switching barriers in wireless are much less severe than digital wired approaches The rapid emergence and evolution of WSN’s, users can realize increased knowledge as well as bottom line payback through use of WSN approaches. Conclusions: The Role of WSN’s in the Process Industry

  29. The enhanced capability made available to the user by WSN’s is a double-edged sword. Poorly thought out approaches for new applications will result in user dissatisfaction and retard the utilization of WSN’s and realization of its benefits. Proper specification of application requirements will identify the available protocols and platforms that are preferred solutions. WSN implementations will not replace all conventional wired solutions but enhance the user’s capability to manage the process using both wired and wireless implementations. A suggestion to users - focus on the best practices of your industry in defining applications requirements and performance expectations rather than the underlying fundamentals of the communication technology. The later is in the domain of the suppliers (instrumentation, component and network developers). An ideal and practical objective would be to have the wireless platform be viewed and perform as a “transparent cable” . Conclusion: Realizing Benefits for Users

  30. Magic

  31. Comparative Technologies

  32. WHY CHOOSE 900MHz? It is important to consider pros and cons of frequency bands when choosing what frequency to use for data transmission. The two most commonly used industrial, scientific, and medical (ISM) radio bands are referred to as the 900MHz and the 2.4GHz bands. Both permit the use of license-free Spread Spectrum radios within them. For the most part, the 900MHz band is used in the Americas. The 2.4GHz band is used (with differing power constraints) throughout most of the world.

  33. WHY CHOOSE 900MHz? • Differences between the characteristics of the two bands, • 900MHz band typically allows for: • higher power and • longer distance transmissions while • 2.4GHz band, with its wider bandwidth, allows for • higher data rates.

  34. WHY CHOOSE 900MHz? Comparing Wave Propagation of 900 MHz and 2.4 GHz Frequencies To demonstrate the basic difference in wave propagation of 900 MHz and 2.4 GHz waves, a quick look at path loss is provided. As waves propagate out from the transmitter, some attenuation of the signal takes place due to properties of the medium (air in most cases). Path loss describes this attenuation as a function of the wavelength of the operating frequency and the distance between the transmitter and receiver.

  35. WHY CHOOSE 900MHz? Path loss is derived from the Friis transmission equation and is defined as: Path Loss = 20 log(4*p*r/λ) dB r is the distance between the transmitter and receiver λ is the wavelength The table below shows how path loss differs between 900 MHz transmitters (λ=0.33 meters) and the 2.4 GHz transmitters (λ=0.125 meters). Frequency10 Meters100 Meters1000 Meters 900 MHz 51.527 dB 71.527 dB 91.527 dB 2.4 GHz 60.046 dB 80.046 dB 100.046 dB

  36. WHY CHOOSE 900MHz? The increased rate capacity of 2.4GHz comes at the cost of radio propagation, or radio distance. The higher 2.4GHz and 5.7GHz frequencies have a much shorter reliable distance than the lower frequencies. In most cases, the higher frequency bands will not operate reliably over the distances required for industrial plants and factories. In industrial plants and factories, the performance of 2.4GHz vs 900 MHz is even worse, with reliable distances dropping to 10-20%. In industrial environments there are very few direct (“line-of-sight”) radio paths - most paths are obstructed and congested by machinery, steel-work, vessels and buildings. The performance of radio in this type of environment is determined by the ability of the radio signal to: 1. Penetrate obstacles, and/or 2. Bend around obstacles, and/or 3. Reflect from obstacles.

  37. Penetrating Obstacles Radio waves decrease in amplitude as they pass through walls. As the radio frequency increases, the rate of attenuation increases - that is, the radio strength dies off faster, and the effect of passing through obstacles is much greater.

  38. Bending around Obstacles Radio waves travel in a straight line; however, a radio “beam” can diffract or bend when it hits an edge in the same way as light can. The angle of diffraction is higher as frequency decreases - or the ability to bend around obstacles increases as frequency decreases. A lower frequency radio signal is "blocked" by an obstacle to a lesser extent as it is able to bend around the obstacle.

  39. Reflections Radio waves also reflect from dense surfaces such as metallic walls or vessels. Very often the radio signal has been reflected several times before it reaches the receiver unit. When a radio signal is reflected, some of the RF power is absorbed by the obstacle, reducing, or attenuating, the strength of the reflected signal. This attenuation increases with frequency. That is, the reflected signal is weaker for higher frequencies. If the path is very congested, with a lot of consecutive reflections, the 2.4GHz signal fades out quickly.

  40. The End Result The end result of the effects of RF power, propagation losses, penetration attenuation, diffraction and reflection loss is that: 2.4GHz has only a very short reliable operating distance in industrial environments - with reliable distances of only around 10-20% of the lower frequency bands. The lower frequency bands reach 5-10 times the distance in plants and factories. In many applications, distances of more than 100 - 300 feet cannot be achieved with 2.4GHz over congested obstructed paths. The information in this document was compiled using direct excerpts from the following three websites: http://www.omnexcontrols.com/Support/Wireless_IO_and__SCADA_FAQs.aspx http://www.maxstream.net/helpdesk/article-119 http://www.elprotech.com/elpro/2_4GHz.htm

  41. WHY CHOOSE 900MHz? Will your product be deployed outside North America? Another difference between 900 MHz and 2.4 GHz solutions is that the 900 MHz radio frequency band is for unlicensed use only in North America, Australia and Israel. Worldwide (including North America, Australia and Israel), 2.4 GHz is an unlicensed radio frequency band. 2.4 GHz products are more universally accepted worldwide, which is why some manufacturers standardized on the higher frequencies.

  42. New 900 MHz FHSS Wireless Sensors • Self-contained, self-powered, process instrumentation (field units) providing… • Wireless process data transmission over secure, 900MHz, spread-spectrum, license-free link to a… • Centralized base radio. WIRE Wireless Link Base Radio Field Unit

  43. New 900 MHz FHSS Wireless Sensors • Up to 100 Field Units can be polled by single Base Radio • Typical range from field units to base radio is up to 2,500ft • Concentrated process data in base radio is then passed through to third-party SCADA system components such as PLCs, RTUs and SCADA Hosts using industry-standard Modbus protocol over a serial link. Wireless Links Serial Modbus Link Base Radio PLC/RTU Field Units

  44. Typical System Schematic Network #1 Serial Connections WAN PLC/RTU Network #2

  45. Product Notes: • Long-lasting battery power source in field units lasts up to 5 years • Field units: Integral antennas (some have optional external high gain antenna) • Base radio: Integral of remote antenna. • 902 MHz - 928 MHz FHSS, frequency-hopping spread spectrum radio. • Secure proprietary “Industrial Wireless” protocol • Standard LCD and 2-button keypad for local configuration and monitoring

  46. Product Notes: • Class I, Division 1 • Some manufacturers offer as much as a 3-Year Warranty • NEMA 4X weather-proof housing • Shock and vibration qualified • High duty-cycle availability • Software for configuration and diagnostics

  47. Many types of Wireless Sensors to choose from……. Gauge Level Switch Input Gauge Pressure WIRE Submersible Level Temperature: RTD Thermocouple Base Radio

  48. RF Communication Options? Exposed Leads Option High-Gain Antenna Option Remote Sensor Option SI10 Switch Input AI10 Multi-Input (Current) AV10 Multi-Input (Voltage) RT10 RTD Temperature TC10 Thermocouple Remote Sensor Option High-Gain Antenna Option GL10 Gauge Level GP10 Gauge Pressure GP10 Gauge Pressure

  49. Windows-based services-management Software: • Field unit configuration interface • Auto-Recognition • Remote Configuration • Provides system diagnostics • Powerful network management tool • Client/server architecture • Installs on: • Single PC’s • Corporate LAN servers for 24/7 Monitoring and Diagnostics • One or more PC’s for multiple services management consoles (including Internet) WIRE

  50. Value Propositions: • Proven 900 MHz FHSS Radio • Wide selection of Instrumentation • Tether-free: NO field wiring • No Integration Required By User • Install “Out of the Box” • Robust design • Not affected by electrical noise • Communicate through obstructions

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