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Power Quality Fundamentals and Monitoring Ross M. Ignall Systems Applications Manager, Dranetz-BMI [email protected] What We Will Cover… - Defining Power Quality and Reliability - PQ References & Fundamentals - Monitoring, Measuring High Reliability Facilities - Case Studies WPT Power Monitoring Hardware Devices •measure and monitor power Data Acquisition Devices Software and Consulting Services •measures physical processes •power quality and distributed generation Aggregation of Distributed Generation •load curtailment of power sales Defining Power Quality & Reliability What is a Power Quality Problem? “Any occurrence manifested in voltage, current, or frequency deviations that results in failure or mis-operation of end-use equipment.” What Does That Mean? Given the quality of supply do I have to worry about problems with my equipment or systems? It’s dependant on your susceptibility. What You Should Be Asking… What is my susceptibility to power problems? What is my economic exposure to such problems? $$$$ Types Of Power Quality Problems Voltage Swells 29% Spikes 8% Interruptions 3% Voltage Sags 60% Who’s Problem Is It? Customer’s Perspective* Neighbor 8% Other 3% Customer 12% Utility 17% * Georgia Power Survey Natural 60% Who’s Problem Is It? Utility Perspective* Customer 25% Utility 1% * Georgia Power Survey Neighbor 8% Other 0% Natural 66% The Big Picture It’s the complete electrical environment, not just the quality of supply What You Should Be Asking… Does my power system have the capacity for my present needs? How about future growth? Be Proactive! An Analogy… “Just because I have blank checks doesn’t mean that I have money in the bank to cash them” Ron Rainville, COO, US Data Centers Some Factoids Power Quality Factoids $50 billion per year in the USA is lost as a result of power quality breakdown. SOURCE: EPRI, 2000 Half of all computer problems and one-third of all data loss can be traced back to the power line. SOURCE: Contingency Planning Research, LAN Times Sandia National Laboratories estimates power quality and reliability problems cost US businesses approx. $150 billion annually in lost data, materials and productivity—60% are sags In 1999, the amount lost as a result of power quality in the US was five times the amount spent on power quality worldwide …The data center houses 45,000 square-feet of computer floor space. In one database, the company has consolidated $1.6 trillion of life insurance information. Energy Decisions, June 2001 During power supply shortages, utilities are generally permitted to have line voltage reductions, so-called “brown outs,” to cope with seasonal power demands…But if equipment is already operating on the low end of nominal voltage then the brown-out may cause excessive heat dissipation in motors and electronic equipment. Building Operation and Management, May 2000 Power Density Factoids Traditional data center or large office building – 20-30 W/sq. ft., Internet Data Center, on-line brokers, web hosts – 100-150 W/sq. ft. A web-enabled Palm Pilot requires as much electricity as a refrigerator Mark Mills Transformation: Former 16 story Macy’s building used to consume 10 W/sq. ft. Now a telecommunications hotel that according to the utility could require 50 W/sq. ft. NY Times, July 3, 2000 Costly Downtime! Industry Brokerage Credit Card Pay Per View Home Shopping Catalog Sales Airline Reservations Tele-Ticket Package Shipping ATM Fees Source: 7x24 Exchange Avg cost of downtime ($/hr) $6,450,000 $2,600,000 $150,000 $113,000 $90,000 $90,000 $69,000 $28,000 $14,400 Introduction to Power Quality Power Grid Review L O A D GENERATOR 13.8kV-24kV TRANSMISSION 115k-765kV DISTRIBUTION 34.5k-138kV 4k-34.5kV 12,470Y/7200V CONSUMER 4160Y/2400 480Y/277V 208Y/120V 240/120V Generation 50/60hz ‘Pure’ Sine Wave Various Voltages Types Chemical Mechanical Nuclear Solar Transmission Those big towers Voltage High Current Small Efficiency of Transmission Power Delivered to the Load Power Supplied From Generator Distribution Typically 13kV Commercial/Industrial - Three Phase, 480/277V Residential - Split Phase 480V 480V 13kV 480V Single Phase Circuit Diagram Is V line Vn L O A D Can Wiring and Grounding Affect Power Quality? “That’s one of the things about living in an old house that drives me nuts. Never enough outlets!” ACTUAL SINGLE PHASE CIRCUIT DIAGRAM Vpcc Is V line Vdp L1 R1 l n2 L3 R3 L2 R2 I n1 Vn L4 R4 Vg L5 R5 I g2 L6 R6 l g1 L O A D Sources Of Power Problems Referenced at the utility PCC (point of common coupling) Utility lightning, PF correction caps, faults, switching, other customers Internal to the facility individual load characteristics wiring changing loads Power Quality References & Terms IEEE Standards Coordinating Committee • SCC-22 • Oversees development of all PQ standards in the IEEE • Meet at both Summer and Winter Power Engineering Society meetings • Coordinate standards activities • Progress reports • Avoid overlap and conflicts • Sponsors task forces to develop standards 1433 Task Force to pull together terms. IEEE & IEC IEEE Standard 1159-1995 Definition of Terms Monitoring Objectives Instruments Applications Thresholds Interpreting Results IEEE 1159 • 1159.x Task Force Data Acquisition & Recorder Requirements for 1159-1995 Combination of 1159.1 & 1159.2 Coordination with IEC standards (61000-4-30 and revisions) New recommended practice to be developed by July 2001 • 1159.3 Task Force Power Quality Data Interchange Format (PQDIF) Format for the exchange of PQ and other information between applications Developed by Electrotek Concepts IEEE 519-1992 Recommended Practice For Harmonics Recommends Limits at the PCC Voltage Harmonics Current Harmonics Ongoing work to modify IEEE 519-1992 Limits for within a facility Frequency dependant International Electrotechnical Commission (IEC) International standards for all electrical, electronic and related technologies. IEC Study Committee 77A – Electromagnetic Compatibility, presently 5 Working groups SC77A/WG 1: Harmonics and other low-frequency disturbances SC77A/WG 2 : Voltage fluctuations and other lowfrequency disturbances SC77A/WG 6 : Low frequency immunity tests SC77A/WG 8: Electromagnetic interference related to the network frequency SC77A/WG 9: Power Quality measurement methods Types Of Power Quality Disturbances (as per IEEE 1159) Transients RMS Variations Short Duration Variations Long Duration Variations Sustained Waveform Distortion DC Offset Harmonics Interharmonics Notching Voltage Fluctuations Power Frequency Variations Transient Characteristics High frequency "event" also called Spike, Impulse Rise time (dv/dt) Ring frequency Point-on-wave Relative versus Absolute amplitude Multiple zero crossings Transients Unipolar Positive Bipolar Notching Oscillatory 200 100 0 -100 -200 Negative Multiple Zero Crossings Transients Possible Causes • PF cap energization Possible Effects • Data corruption • Lightning • Equipment damage • Loose connection • Data transmission errors • Load or source switching • Intermittent equipment operation • RF burst • Reduced equipment life • Irreproducible problems Power Factor Correction Capacitor Transient A transient power quality event has occurred on DataNode H09_5530. The event occurred at 10-16-2001 05:03:36 on phase A. Characteristics were Mag = 478.V (1.22pu), Max Deviation (Peak-to-Peak) = 271.V (0.69pu), Dur = 0.006 s (0.35 cyc.), Frequency = 1,568. Hz, Category = 3 Upstream Capacitor Switching RMS Voltage Variations Instantaneous (0.5 - 30 cycles) Sag (0.1 - 0.9 pu) Swell (1.1 - 1.8 pu) Momentary (30 cycles - 3 sec) Interruption (< 0.1 pu, 0.5 cycles - 3s) Sag Swell Temporary (3 sec - 1 minute) RMS Voltage Variations Sag 200 150 100 50 0 -50 -100 -150 -200 Swell Interruption SAG SOURCE GENERATED DURATION fault clearing schemes may be series of sags (3-4) MAGNITUDE distance from source feeder topology cause LOAD CURRENT usually slightly higher, decrease, or zero PQ Rule For a source generated Sag, the current usually decreases or goes to zero PQ Rule For a source generated Sag, the current usually decreases or goes to zero SAG LOAD GENERATED DURATION type & size of load usually single event per device MAGNITUDE type & size of load wiring & source impedance LOAD CURRENT usually significantly higher PQ Rule For a load generated Sag, the current usually increases significantly. 4000 3000 2000 Volts 1000 0 -1000 -2000 -3000 -4000 2000 1500 1000 Amps 500 0 -500 -1000 -1500 -2000 -2500 12:09:54.40 12:09:54.45 CH A Vo lts CH D A m ps CH B Vo lts 12:09:54.50 CH C Vo lts 12:09:54.55 CH D Vo lts CH A A m ps 09/24/00 12:09:54Threshold crossed: 2280.0 V CATEGORY: Short Duration Momentary Sag Magnitude: 2160.0 V Duration: 2.901 sec. 12:09:54.60 CH B A m ps 12:09:54.65 CH C A m ps Motor Starting - Another Cause of Sags Timeplot Chart Volts Amps 222.5 900 CHA Vrms CHA Irms 800 220.0 700 217.5 600 215.0 500 400 212.5 300 210.0 200 207.5 100 205.0 09:49:00.5 09:49:01.0 09:49:01.5 09:49:02.0 CHA Vrms 09:49:02.5 CHA Irms 09/13/96 09:49:00.50 - 09/13/96 09:49:04.00 09:49:03.0 09:49:03.5 0 09:49:04.0 Min 206.11 1.40 Max Median 222.25 219.19 847.71 207.16 Motor Starting – Inrush Current with decay Waveforms Vo lts Amps 400 1500 300 1000 200 500 100 0 0 -100 -500 -200 -1000 -300 -1500 -400 -500 09:49:00.8 09:49:01.0 09:49:01.2 09:49:01.4 CHA Vo lts 09:49:01.6 CHA Amps AI RMS Norm to Hi at 09/13/96 09:49:00.967 09:49:01.8 09:49:02.0 -2000 09:49:02.2 SWELLS Sudden change in load Line-to-ground fault on another phase Often precede a sag SWELLS when Load Drops Off 750 500 Volts 250 0 -250 -500 -750 3000 2000 Amps 1000 0 -1000 -2000 -3000 14:44:04.20 CH A Vo lts CH C A m ps 14:44:04.25 14:44:04.30 CH B Vo lts CH D A m ps 14:44:04.35 CH C Vo lts 14:44:04.40 CH D Vo lts 14:44:04.45 CH A A m ps 14:44:04.50 CH B A m ps Voltage Variations Sags/Swells Possible Causes Possible Effects • Sudden change in load current • Process interruption • Fault on feeder • Data loss • Fault on parallel feeder • Data transmission errors • PLC or computer misoperation • Damaged Product Magnitude & Duration Visualization • CBEMA • ITIC • Equipment Susceptibility • 3-D Mag-Dur • DISDIP IEEE 446 - 1995 Limits Information Technology Industry Council (ITIC) Curve Another Use of ITIC Curve but vendor had tighter tolerances for outputs Another Perspective – 3D Mag-Dur Histogram Frequency • Usually not the utility • Sources of frequency problems Co-gen UPS Engine generator systems • Clocks run fast 11 12 1 10 2 3 9 4 8 7 6 5 Harmonics Event waveform/detail Event waveform/detail Amps 4 % o f FND 250 3 200 2 1 150 0 -1 100 -2 50 -3 11:19:27.84 11:19:27.86 11:19:27.88 11:19:27.90 CHD Amps 11:19:27.92 -4 11:19:27.94 0 Thd H02 H04 H06 H08 H10 H12 CH D Amps Waveform event at 10/14/93 11:19:27.75 Total RMS: 1.44 Amps DC Level : -0.04 Amps Fundamental(H1) RMS: 0.48 Amps Total Harmonic Distortion (H02-H50): 246.72 % of FND Even contribution (H02-H50): 73.96 % of FND Odd contribution (H03-H49): 235.38 % of FND Waveform event at 10/14/93 11:19:27.75 H14 H16 What is a harmonic? An integer multiple of the fundamental frequency Fundamental (1st harmonic) = 60hz 2nd = 120hz 3rd = 180hz 4th = 240hz 5th = 300hz … Linear Voltage / Current No Harmonic Content voltage current Non-Linear Voltage / Current Harmonic Content voltage current NEC 1996: Non - Linear Load "A load where the waveshape of the steady-state current does not follow the waveshape of the applied voltage." voltage current Harmonics Steady state distortion Periodic or continuous in nature IEEE-519-1992 / US harmonics IEC 61000-3-2&3 European harmonic limits Transformer Magnetizing Current 1.50 1.00 0.50 Amps 0.00 -0.50 -1.00 -1.50 0.02 0.03 0.05 Time (Sec) 0.07 0.08 Harmonic Measurements Total Harmonic Distortion (THD) Ratio, expressed as % of sum of all harmonics to: Fundamental (THD) Total RMS Load Current (I TDD only) Individual Harmonics 2, 3, 4, 5, 6…50+ Fourier Transform, FFT, DFT Interharmonics Content between integer harmonics Composite Waveform Event waveform/detail Vo lts 50000 40000 30000 20000 10000 0 -10000 -20000 -30000 -40000 -50000 05:35:31.26 05:35:31.28 05:35:31.30 05:35:31.32 05:35:31.34 CH A Vo lts 05:35:31.36 05:35:31.38 05:35:31.40 Harmonic Spectrum Event waveform/detail % o f FND 12.5 10.0 7.5 5.0 2.5 0.0 Thd H05 H10 H15 H20 CH A Vo lts T otal RMS: 24882.56 Volts DC Lev el : 880.46 Volts Fundamental(H1) RMS: 24725.89 Volts T otal Harmonic Distortion (H02-H50): 10.60 % of FND Ev en contribution (H02-H50): 7.97 % of FND Odd contribution (H03-H49): 6.99 % of FND H25 H30 PQ Rule Even harmonics usually do not appear in a properly operating power system. Symmetry Positive & Negative halves the same: Only odd harmonics. If they are different: Even & Odd harmonics Harmonics (sustained) Possible Causes • Rectified inputs of power supplies • Non-symmetrical current • Intermittent electrical noise from loose connections Possible Effects • Overload of neutral conductors • Overload of power sources • Low power factor • Reduced ride-through Electronic Loads Cause Excessive Neutral Currents Electronic Loads Phase A (50 Amps) Phase B (50 Amps) Phase C (57 Amps) Neutral (82 Amps) Additive Triplen Harmonics Equipment Susceptibility Least Susceptible Electrical Heating Oven Furnaces Most Susceptible Communications Data Processing Zero crossing Clock Circuits Transformers, Motors, other inductive loads IEEE 519 Harmonic Limits Limits depend on ratio of Short Circuit Current (SCC) at PCC to average Load Current of maximum demand over 1 year For example, Isc/IL < 20, odd harm <11 = 4.0% Isc/IL 20<50, odd harm < 11 = 7.0% Isc/IL >1000, odd harm > 35 = 1.4% IEEE 519 Harmonic Limits Voltage Harmonic Limits depend on Bus V For example, 69Kv and below, ind. harm = 3.0% 69Kv and below, THD= 5.0% 161kv and above, ind.harm = 1.0% 161kv and above, THD = 1.5% Harmonics Demo Tool 150 100 50 0 -50 -100 -150 0 50 100 CH A 150 CH B CH C 200 Neutral 250 Voltage Unbalance Several ways to calculate Small unbalance can cause motor overheating (3% results in 10% derating) Caused by Unequal loading Unequal source impedance Unequal source voltage Unbalanced fault Voltage Fluctuation Voltage Fluctuation Amplitude variation 1-30 Hz Extent of light flicker depends on type of lights amplitude and frequency of variation person's perception Typical causes High current loads, like arc furnaces Windmill-generated power Voltage Flicker Timeplot 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 02/06/2002 02/08/2002 02/10/2002 02/12/2002 02/14/2002 02/16/2002 CHA VPst() CHB VPst() CHC VPst() 02/07/2002 00:05:00 02/18/2002 02/20/2002 How Many Can You Find? Suggested References [1] Electrical Power Systems Quality, R.C. Dugan et al, McGraw-Hill, 1996 [2] Handbook of Power Signatures, BMI, 2nd Edition, 1993 [3] IEEE Standard 1159-1995, IEEE Recommended Practice for Monitoring Electric Power Quality [4] IEEE Standard 519-1992, IEEE Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems [5] IEEE Standard 1250-1995, IEEE Guide for Service to Equipment Sensitive to Momentary Voltage Disturbances [6] IEEE Standard 446-1995, IEEE Recommended Practice for Emergency and Standby Power Systems for Industrial and Commercial Applications [7] IEEE Standard 142-1991, IEEE Recommended Practice for Grounding of Industrial and Commercial Power Systems [8] Federal Information Processing Standards Publication (FIPS PUB 94) Guideline on Electrical Power for ADP Installations Case Study Laser Printer TIMEPLOT - LINE VOLTAGE vrs NEUTRAL-GND VOLTAGE Vl-n= 120 --> 108 45 seconds Vn-g = 0 --> 6V SAG when heater turns on V l-n I load V n-g Overlay Waveforms - Heater turn on Current Waveform - heater on HARMONIC DISTORTION - heater on 2.3% Harmonics V l-n 4.4% Harmonics I load Harmonics V n-g Waveforms when heater turns off V l-n I load V n-g Harmonic Distortion - Idle 2.3% Harmonics V l-n 94% Harmonics I load Harmonics V n-g Current With Printer Idle EQUIVALENT CIRCUIT I Load V Load 0.47 ohms + Source Impedance 10.4A @ 117V 0.6A @ 121V 121 Vac Idle Load 202 ohms + V n-g - Heater Load 11.9 ohms - OBSERVATIONS and PARAMETERS Nearly Sinusoidal Current – Low Harmonic Distortion (4%) Voltage and Current In-phase – Power Factor Near One Flat-topping of Voltage when Idle Corresponds with Current Pulse OBSERVATIONS and PARAMETERS Line Voltage Negative Transient on Turn on – Corresponds with Vn-g Positive Transient Nearly Constant Repetition Rate SIMILAR SITUATIONS • Coffee Pot • Coke Machine • Heat Pump Monitoring, Measuring & Managing High Reliability Facilities Why Monitor Your Electrical Supply? Paradigm Shift? You may no longer be able to rely on the utility to be your primary source of power! Be Prepared Why Monitor Your Electrical Supply? • Quality of supply is of paramount importance • Huge investment in protection & mitigation is not a guarantee! • You have a high economic exposure • Your facility is core to your business or maybe is your business • You already monitor other critical items • Your electrical environment is just as important • You need to balance your needs with available supply • Loading, cost allocation, etc You May Already Monitor Your Facility • Traditional Data Center • Building Management Systems (BMS), Human Machine Interface Software (HMI) • Wonderware, Sitescan, ALC, Datatrax, etc • Via Bacnet, Lonworks, Incomm, modbus, etc • Internet Data Center • Network Operations Center (NOC) • HP Open View, etc • Via SNMP What You May Already Monitor • Traditional Data Center • UPS - On Bypass, other alarms • Traditionally do not measure quality • Sub Metering • HVAC, Fire, Security • Internet Data Center • Network/System Health • HVAC, Fire, Security • Electrical Supply is often overlooked • Quality of supply, Energy/cost allocation • Power monitoring can interface with existing systems for single point alarming, logging, etc… Approaches to Power Monitoring Reactive — Forensic, after the fact. Proactive — Anticipate system dynamics Be Proactive! Reactive Approach • Problem Solving, hopefully you’ll find it! • Portable instrumentation typically used Proactive Approach • Permanently installed monitoring systems • Anticipate the future – on-line when trouble occurs • Monitor system dynamics • Preventive Maintenance, Trending, identify equipment deterioration Be Proactive! Power Quality vs. Power Flow • Power Quality Monitoring - Quality of Supply • Monitor for harmful disturbances, harmonics, etc Microsecond, Sub-Cycle Measurements • In close accordance with IEEE 1159 & IEC • • Power Flow Monitoring - How much, cost, when & where? • Energy & Demand, Measured over seconds • Be Careful! False sense of security • Blind to common PQ problems Use a PQ instrument for PQ monitoring! Comprehensive Power Monitoring • Combined Power Quality and Flow • Monitor PQ at critical locations • Utility service, UPS, PDU’s, loads • Energy provided along with PQ • Monitor Energy at less critical locations & individual loads • Loading • Sub Metering • Cost Allocation, etc… Emerging Technologies • Reduced Cost • Web monitoring • Networked systems • Native web access • Maximize Assets • Sharing of information among systems and groups within the organization • Expert Systems • Enterprise Systems • Pull together various separate systems Enterprise Systems • Traditional Facilities • Power monitoring system interfacing with building management, HMI or other systems • Notification, metering, trending • OPC. Modbus, e-mail • Internet Data Center • Interface with Network Operations Center (NOC) • Notification, metering, trending • Simple Network Management Protocol (SNMP) Expert Systems • Reduced budgets means less people! • Less expertise • Analysis of Data in order to Identify Problems • Automatic, no user intervention, results embedded in data • Identify certain disturbances and directivity. • Upstream or downstream • Answers Questions Such As… • Was that Sag from the utility or within my facility? Expert Systems • UPS Performance Verification • Correlation of Input vs. Output • Verify continued performance over time • Proactively identify downstream problems • Monitor UPS status via analog/contact inputs • Remotely access UPS status signals • Compare recorded data to UPS status Expert Systems Expert Systems Automatically Identifies the Transient as a Capacitor Switching Operation Where To Monitor? • Utility Service Entrance • Evaluate your energy provider • Monitor redundant feeds • UPS Output • Is your UPS working as designed? • Evaluates critical bus as problems could be downstream • PDU/Distribution • Provides the ability to identify the source of a problem. Why did that breaker trip? • Loading/Cost allocation • Actual loads Case Study DHL Airways Call Center • Tempe AZ • Services DHL customers nationwide • Newly Constructed, went online in June 2000 • Toshiba 7000 Series UPS • Three 300KVA parallel redundant units • Facility manager has nationwide responsibilities • Current Expansion Plans DHL Objectives • Benchmark performance • Ensure future reliability • Easily troubleshoot any problems that may occur • Automatic notification • Remotely monitor over DHL network • Since the facility is new and due to its critical nature, monitoring approach was very proactive DHL Monitoring System • Monitoring Points • UPS Input (Utility Supply) • UPS Output (Critical bus) • Connected to DHL Intranet • Dial-up modem connection • Web browser access from anywhere within DHL • Automatic E-mail notification • Web browser access from anywhere with a dial-up connection Known Problems? • None! • Facility operating as planned • No Outages or other major problems identified • No UPS Alarms Utility Supply 50+ Disturbances in the first few months UPS Output No disturbances Utility Monitoring Summary • Uncovered problems with the utility supply • 50+ disturbances recorded over a 2 month period. • Sags, transients, waveshape distortion • Results reported to the utility, they did not know • Utility investigation • Faulty relay caused the majority of the disturbances. Corrected UPS Output Monitoring Summary • No disturbances on the conditioned UPS output • Output regulated to within manufacturers specifications • UPS mitigated many disturbances on the utility feed • Did what they paid for • Justified the investment Conclusion • Being proactive uncovered problems with the utility supply that required correction • Continuous monitoring proved power conditioning equipment worked as design and to manufacturer’s specifications. Protected loads were unaffected • Provided justification to management for power monitoring systems at other key facilities • Load profiling helping to determine power requirements of a planned expansion Case Study Major Financial Institution • New York City • Worldwide company with several facilities in NY & NJ • 3 UPS Modules •2 static, 1 rotary Problem • Utility Sag • Damaged elevator controls • No UPS alarms • No reported problems with critical systems 02/19/2002 00:29:29.26 PMODULE INPUT Temporary Sag Rms Voltage AB Mag = 366.V (0.76pu), Dur = 3.300 s, Category = 2, Upstream Sag 02/19/2002 00:29:29.26 SYSA Input Temporary Sag Rms Voltage AB Mag = 353.V (0.73pu), Dur = 3.300 s, Category = 2, Upstream Sag 02/19/2002 00:29:29.26 SYSB Input Temporary Sag Rms Voltage AB Mag = 372.V (0.78pu), Dur = 3.300 s, Category = 2, Upstream Sag Utility Sag Utility Supply RMS Trend Utility Supply Waveforms Corresponding UPS Swell Utility Supply UPS Swell UPS Output Conclusion • Utility sags damaged elevator controls. • Corresponding UPS Swell coincident with Utility return to normal. • Cause of Swell being investigated… • Possible effects of Swells: • Damaged power supplies and other devices. • Without monitoring would have never seen this. The next time it could be worse. Case Study Federal Aviation Administration Air Route Traffic Control Center (ARTCC) Monitoring System Simplified Air Traffic Flow ARTCC ARTCC TRACON ARTCC TRACON Tower Tower Your Flight FAA’s Objectives • Monitor critical points throughout each ARTCC • Determine present status of each ARTCC Facility • Is the electrical supply operating within design parameters? • Catch problems before they occur • Change approach from Reactive to Proactive • Correlate power quality to status indicators, panel meters, transfer switch positions, etc FAA’s Objectives • Benchmark long term performance in order to improve reliability • Compare measured parameters to simulations • Have web browser access from anywhere within the FAA system • Local ARTCC personnel • OKC Airway Operational Support (AOS) personnel Monitoring System • Monitor 15 points for quality of supply & energy • Utility Service • Generators • UPS’s • Key distribution points • Critical Power Centers • In parallel monitor other data such as • Transfer switch & breaker positions • Panel meters • Misc indicators • Web based access to each site via intranet Initial Results • Key points operating out of design specs • Ex: Adjust transformer taps • Routine maintenance not always performed as per procedures • Wiring inconsistent with drawings Power Quality Fundamentals and Monitoring Thank You! Questions? Ross M. Ignall Systems Applications Manager, Dranetz-BMI [email protected]