EATONENSC
MAGAZINEg2ni0taYrebalersApFrancisco,Ca lifornia!CeVolume 2 Edition 1 Spring 2019r i l 8 th190ht2- 11a SnEATONENSC.COMEATONENSC.COM1
It is great to be in San Francisco for our 20th annual ENSC!We could not have picked a better venue and thankfulthat PG&E wanted to host the event. A couple factoidsthat I have learned, in preparing for this event, that SanFrancisco has the 2nd largest Chinatown outside of Asia andthe iconic Golden Gate Bridge, as we know is not goldenbut a reddish orange tint, it’s called International Orange.The surprising thing is that the color comes from the primerapplied to protect the bridge. The architect loved it so muchthat he made it the official color.Besides the great venue, this edition of ENSC magazinecontains some great articles. Make sure you check out thearticles on Network Testing Philosophy by Richard Hotchkissfor further education and the article on how safety haschanged in Network environments written by Tom Thodefrom Xcel.For 2020, the ENSC will be heading to Texas to join our hostCenterPoint Energy, arrangements are already in work tomake sure the educational content continues to give back tothe network community.I look forward to seeing all of you in Texas!Respectfully,Mark FaulknerProduct Line ManagerEatonENSC MAGAZINE VOLUME 2 EDITION 1 SPRING 2019ENSC Advisory CouncilMembers:Maria LyPacific Gas and ElectricShane PowellAlabama Power CompanyRyan BradeenAvista Corp.Rick KernanXcel EnergyRobert SpelmanPepco Holdings Inc.ENSC MagazineTony Oruga, P.E.Eaton1520 Emerald Rd.Greenwood, SC 29649AntonioROruga@eaton.com(864) 330-2461
ENSC — The Network Solutions MagazineTABLE OF CONTENTSUnderstanding ArcFlashDave Loucks, Eaton , Power Solutions ManagerPacific Gas and Electric System Improvement PlansMaria Ly, PG&E, Network Manager – Asset ManagementDustin Dear, PG&E, Network Program ManagerMV GIS For Network SubstationsShane Powell, Alabama Power Company, Network Distribution MangerLucas Coffey, Alabama Power Company, Network Engineer5810Evaluating Duct Sealing Methodsand Materials to Mitigate Risk13History of Network SafetyTom Thode, Xcel Energy, Operations Manager16Network Protector Testing Overviewfor CM52 with MPCV Relay18SPONSORS: Eaton Automation Systems Neenah Foundry21Roy Middleton, Mac Products, Network ConsultantRichard Hotchkiss, Eaton, Network Lead TechnicianPower Systems Integrity Exacter Eaton CYME Burns and McDonnellSiemens Eaton Network SolutionsEATONENSC.COM3
Hosted by:SAVE THE DATEApril 6 - 9 2020ththSponsored by:21 st Annual ElectricalNetwork Systems ConferenceHOUSTON, TX
Understanding ArcFlashDave Loucks, Eaton, Power Solutions ManagerYou are likely already acutely aware of the danger of arc flash.You are also likely aware that the danger from an arc flashtends to increase: As the available fault current increases,As the time you are exposed to the fault current increases andAs the distance between you and the arc decreasesUnfortunately, in underground utility networks, these factors tendnot to work in our favor. Available current can be very high. Thetime a fault persists can be measured, not in milliseconds, but inmany seconds or longer. Many times work is performed in confinedspaces, which limits a worker’s ability to run away from anarcing event.But even so when an arc flash event does occur, seriousconsequences can include: InjuriesMedical bills and insurance reratingFines and potential lawsuitsEquipment damageDelays and downtimeImpact on employee morale and community public relationsFor these reasons every appropriate effort should be taken tolack of light in the vault as well as the dark face shield which hadmade it difficult to see. He was wearing safety glasses which mayhave saved his eyes.He fully recovered, but he will be the first to tell you that he neverwants to experience that again.What can be done to reduce danger?With such high currents, the lack of overcurrent tripping andconfined spaces, what can be done to reduce the danger of an arcflash event on such a network?1.Perform an incident energy analysisKnowing the worst-case incident energy levels should anarcing event occur allows you to take appropriate actionto protect people and equipment. This study should beperformed by power systems engineers skilled in the study ofarc flash and who fully understands the equipment, the settingsand the consequences of changes in equipment settings.In this case study, perhaps understanding that a serious faceburn was possible might have changed how the workwas performed.2.Equip staff with appropriate personal protectiveequipment and toolsWith the known incident energy levels, you can provide yourstaff with the right PPE and equipment to keep them safe.Remember, though, PPE should be considered the protectionof last resort. An arc flash event can still result in equipmentdestruction and down service, not to mention potentiallyreceiving bad publicity from either the outage alone, orpotentially the fire and explosion that can occur. Also, if thePPE that is provided (like the dark face shield) hinders work,look for alternatives.3.Post warning labels and boundary markersMake sure people who have access to areas where arc flashincident energy can exceed the 1.2 cal./cm2 are suitablywarned, both with labels that describe the hazard as well asclearly visible “do not cross” boundary markers. In some areas,such as underground vaults, the energy levels could prohibitentering while energized. In our case study above, estimatedavailable fault current was 70 kA – high enough that would, anddid, cause a severe injury. However, arc flash hazards are notthe only concern. Vault flooding can cause an electrocutionhazard. In both cases (high available fault current andpossibility of flooding), remote monitoring and control of thatvault’s assets should be considered.4.Implement training program and include periodicrefresher classesOSHA requirements and common sense dictate that peoplereceive regular refresher training.understand the potential hazards, train and equip your staff anddeploy techniques and programs to minimize the danger ofarc flash.Arc Flash Incident Case StudyIn 2015, a highly skilled worker performing upgrades within anAvista 480V network vault experienced an arc flash event. Duringa routine protector change-out the cableman was working on liveequipment and the ladder supporting him slipped. This resulted ina chain reaction of events. The blanket that was used to cover thenetwork protector tank below moved just enough to expose theterminal on the tank. Unfortunately, as the ladder shifted, the tool inthe hand of the worker glanced against the terminal housing, andgrounded the energized collector bus via a non-insulated tool.Image of the burned tool held by the workerThe resulting arc flash was severe enough to throw the workeroff the ladder with sufficient force to send him across the vault andland against an opposite wall. However, the most severe injurieswere facial burns on his forehead, nose, chin and cheeks. While hewas wearing PPE, he had removed his protective hood due to theEATONENSC.COM5
5.6.Reduce available fault current (if possible)This may not be possible in underground networks, but ifhigher impedance transformers or open tie switches can beemployed to reduce fault current, they should be evaluatedto see if that will have a benefit on your circuit. Reducing faultcurrent doesn’t, however, always reduce incident energy. Inthe special case of circuits that are protected with currentlimiting devices, the extremely fast clearing times of thesekinds of devices may result in lower incident energies fromhigher available fault currents. This may seem counter-intuitiveso verify with a power systems engineer trained to performthat analysis.Shorten clearing timesNetworks are highly available systems where faults are typicallycleared not from overcurrent relay operation but from the faultsburning clear. However, when working on live equipment theneed for service continuity must be balanced by the need toprotect the worker. Also, not all circuits are meshed networks.Spot networks and more conventional, radial, loop, ring andprimary or secondary selective circuits are also common.For this reason, certain kinds of protective functions may bepossible to include in certain cases.a.Directional and differential relayingNetworks commonly use directional Watt and VAR relaysto detect the direction of real and reactive energy flowingDeploy ARMSSimilar to the problem with directional and differentialsensing, ARMS (Arcflash Reduction Maintenance System) isa method of providing more sensitive overcurrent trippingwhen equipment must be serviced live. When activated,ARMS removes intentional delays from protective deviceswhile simultaneously reducing the pickup level neededto initiate an instantaneous trip. The highest performingARMS systems operate far faster than even instantaneoustripping elements. ARMS first became popular in 2011when it was introduced as a solution to meet article 240.87in the 2011 National Electrical Code. Note that there areother solutions mentioned in that code section, with eachoffering certain pros and cons compared to ARMS.CONS(not as practical as ARMS)Zone Selective InterlockingAlways on vs ARMS needing to beswitched on demandSlower to respond (higher incidentenergy released than ARMSprotected circuit)Differential relayingAlways on vs ARMS needing to beswitched on demandExpensive (requires large, matchedCTs to be mounted on eachincoming and outgoing conductor)Active arc flash mitigation (light)Could be faster ONLY if suitablecrowbar device installedCould nuisance trip from lightejected from switching deviceunder normal operationInstantaneous setting below arcingcurrentComplex arcing fault calculationsneeded (difficult to know precisely).Potentially slower than true ARMSInstantaneous override belowarcing currentComplex arcing fault calculationsneeded (difficult to know precisely).Potentially slower than true ARMSAn approved equivalent means6b.PROS(better than ARMS)Methodc.in a vault and to open a network protector as appropriate.However, this typically addresses faults on the primary sideof the network transformer which may be some distanceaway. For faults occurring within the vault, the directionaltripping usually provides less benefit. If it is possible tointerrupt power flowing into a vault, it may be possibleto install bus differential protection to monitor currententering and leaving a vault. Such a solution would bemore likely used on spot networks or on more loop, ringor selective systems.UnknownDeploy Arc Flash relay (light / current) detectionAs mentioned above, detecting the burst of light after anarc flash is only half the battle in reducing energy of an arcflash event. Challenges remaining include: How to quickly extinguish the arc. Considering thatto effectively reduce the energy released from an arcflash event, not only must fault be detected, but alsoextinguished. And this must be done quickly! Thepeak pressure wave (which occurs within the first¼ cycle [4.2 ms at 60 Hz]) means that any effectiveENSC MAGAZINE VOLUME 2 EDITION 1 SPRING 2019Risk. Who determines? AHJ? interruption cannot be slower than 4.2 ms (0.25 cyc).Nuisance tripping from rogue light emissions of airbreak devices. Consider that an air break interruptingdevice generates a light pulse very nearly identicalto a light pulse of an arc flash event. Withoutsophisticated discrimination, every time that such adevice interrupts, there is the potential for nuisanceoperation from that rogue light emission.Finally, even with the most sophisticateddiscrimination (usually with a combination of light
In several cities, as early as 1925, networks were an acceptedmethod of supplying power. With cables and terminationsunder our streets potentially being over 70 years old, howmight those bad cables be located? This will be a topicfor an article in the next issue, but essentially there areseveral methods.and current sensing and other tricks), detecting thefault is only half the battle – the current must still beinterrupted fast enough to justify the investment.This is a problem when using mechanical devices.Such devices having moving contacts with mass andinertia. It doesn’t matter if an arc flash is detected ina nanosecond if the device requires 80 ms to clearthe fault! The arc flash will continue for 80 ms. Theexplosive peak pressure wave (4.2 ms till peak) haslong since occurred and the commensurate operatorinjury and equipment destruction has occurred alongwith it.a.Actions to reduce arc flash riskWhile many of the technologies listed above are quite applicablein many utility systems, they aren’t as relevant to undergroundnetworks and vaults. The constrained space, lack of overcurrenttripping as well as the extremely high available fault levels (bydesign), make these locations dangerous places for live work.For this reason, companies should examine practical methods ofperforming the tests, monitoring and maintenance remotely.1.c.Adopt remote operationRemoving the worker from the vicinity means that the eyes,ears, touch, nose and ability to move things is no longer on siteeither. Not only is the situational awareness lost, but the abilityto open, close, disconnect and move things is lost. A suitablereplacement to a physical worker will change based on whatwould have needed to have been done by that worker.a.b.2.b.Remote monitoringNetwork protectors have, for many years, includedcommunications that can be integrated into existingSCADA systems. Later enhancements allowed those sameprotectors to integrate safely and securely into encryptedutility IT networks. But can the telemetry system providethe information that a local worker would have been ableto provide? The answer (and cost) depends on what youneed, and how fast you need it. Some examples includei.Protector state (closed, open/floating, open/locked out, etc.)ii. Current (phase circuit as well as control)iii. Voltages (both circuit as well as control)iv. Phase angle (differential across NWP)v. Watt and VAR (magnitude and direction)vi. Temperature (transformer, protector, vault)vii. Presence of waterviii. Sound and vibrationRemote controlWhen monitoring alone isn’t sufficient, and actions such asopening and closing or even permanently disconnectingprotectors is needed, something else besides a telemetrysystem may be needed. With network protectors, inaddition to the ability to act upon ROBO (remote open /block open) commands, some network protectors take thisa step further and permit remote racking of the switchingdevice to add another level of protection.Predict and prevent faultsNetwork cabling can be subject to water encroachment, animaland insect infestation and just general degradation due to age.d.By comparing, normalizing and filtering currents andvoltages collected from a diverse set of metering devices(NWP, AMI, substation meters and relays, etc.), a realtime state-estimation analysis is performed. The resultof this analysis is compared to the offline model of thesystem. Excessive voltage drop can point to clearedlimiters or other failures in continuity between two points.Also, higher than normal resistance on a set of phaseconductors means that those conductors will heat (andpotentially degrade and fail) more quickly.Arcing ground faults may persist for extended timesduring which they consume power in a “stochastic”(random) method that is detectable using algorithmsthat can measure randomness in the current and voltagepatterns.In medium voltage systems such as switchgear, coronaand partial discharge events are detectable usingembedded computer systems connected to I/O that canretrieve high frequency electromagnetic emissions fromthose discharge events.Using temperature and IR (pyrometer) sensing ofconductors, terminations and equipment, early warning offaster than normal degradation can be detected. Failingconnections, for example, have higher resistance. Higherresistance means greater voltage drop and higher heatloss. Arrhenius equations can be applied to estimate thereduction in equipment service live.3.Redirect blast energyOne final consideration is the use of arc-resistant equipment.Arc resistant equipment is designed to contain and redirectany internal arc flash event’s energy safely away for a worker.4.Isolate Network ProtectorA network protector should be completely dead beforeworking on the equipment. If the station breaker is opened,then the primary is de-energized but other network protectorson that same feeder are also opened - dropping contingency.The best option is the use of a localized primary switch on themedium voltage side of the network transformer. This will avoidhaving other network protectors open where the work is beingdone on the same feeder.Note the high voltage side is not the only consideration. Thenetwork side is always energized and is not within the confinedspace of the network enclosure, where work is being done. Adisconnect external to the enclosure such as VisoBlock, Pringleswitches, or a disconnect link or fuse should be used to fullyisolate and protect the worker.Arc flash events can cause devastating injuries topeople, equipment and company’s reputations.Take the time to study your system and performthe studies and methods recommended here.EATONENSC.COM7
Pacific Gas and ElectricSystem Improvement PlansMaria Ly, PG&E, Asset ManagementDustin Dear, PG&E, Network Program ManagerHeadquartered in San Francisco, Pacific Gas & Electric (PG&E) servesapproximately 5.4 million electric customers in northern and centralCalifornia. Due to recent gas pipeline and wildfire events, scrutiny on safeoperations from the public, regulatory, and governmental agencies has neverbeen higher.PG&E’s network system nestles in downtown San Francisco and across thebay in downtown Oakland. It consists of a total of 12 network groups, 69feeders with approximately 1350 network transformers, network protectors, andapproximately 190 circuit miles of primary and 100 circuit miles of secondarycables. These electrical facilities are located in very close proximity to the public.Proactive programs, such as equipment maintenance / replacement and conditionmonitoring, focus on preventing a catastrophic failure. Although the frequencyof these failures can be reduced, the risk cannot be completely eliminated.Underground vault explosions, although not a common occurrence, canresult in significant property damage and serious injuries to the public andPG&E personnel.EJIW cover (installed)Venting Cover ProgramIn 2010, PG&E began a program to replace traditional manhole cover with aventing cover, designed to remain in place in the event of an explosion in the vault.These covers are designed to prevent hazards associated with a 250 pound coverbeing launch above ground, as well as minimize the explosion energy by reducingoxygen intake. Efficacy testing was performed at the EPRI Lennox facility using astandard PG&E vault and lift-out panels.PG&E started the program with the Swiveloc covers and more recently installedventing covers manufactured by East Jordan Iron Works (EJIW). Through2018, PG&E have installed over 5,700 covers, with prioritization based on highpedestrian traffic areas in San Francisco such as parade routes and public marketplaces. This is a system-wide program that will eventually replace most manholecovers in PG&E’s electric system, approximately 13,200. Since program inception,there have been a few cable failures where the installed covers have demonstratedto be effective.Venting ManholeCover Bracing SystemSome of the key program challenges: Standard cover sizes were developed which are applicable forestimated 75% of the locations. The remaining 25% locations would notaccommodate the standard covers due to the uniqueness of the originalinstallation (i.e., non-standard size, double lip steel ring, etc.) or requirerepair work to address vault structure
Product Line Manager Eaton ENSC Advisory Council Members: Maria Ly Pacific Gas and Electric Shane Powell Alabama Power Company Ryan Bradeen Avista Corp. Rick Kernan Xcel Energy Robert Spelman Pepco Holdings Inc. ENSC Magazine Tony Oruga, P.E. Eaton 1520 Emerald Rd. Greenwood, SC 29649 AntonioROruga@eaton.com (864) 330-2461 ENSC MAGAZINE VOLUME 2 EDITION 1 SPRING 2019 e h C e l e b r a t .
with representatives from the Anatomy sector. These relate to the consent provisions of the Human Tissue Act 2004 (HT Act), governance and quality systems, traceability and premises. 3. The Standards reinforce the HT Act’s intention that: a) consent is paramount in relation to activities involving the removal, storage and use of human tissue; b) bodies of the deceased and organs and tissue .
The Development of the Baldrige Excellence Framework and Its Criteria In 1987, the Deputy Director of the National Measurement Laboratory of the US National Bureau of Standards (NBS), Curt Reimann was tasked by President Ronald Reagan, the US Congress, and the director of NBS to create a set of criteria (i.e., standards) to help US manufacturers compete in a global economy. The idea for the .
and confirm that they have no conflict before accepting the appointment. External examiners must advise the Quality & Academic Standards Office immediately via email at pgtexamining@lshtm.ac.uk if a declaration of a conflict of interest needs to be made before appointment or arises during their term. 1. The LSHTM will not appoint anyone in the following categories or circumstances as an .
Boris Fausto, vem cobrir parte desta lacuna do período do Estado Novo. O autor traz contribuições valiosas para o entendimento do modo de pensar e de como as pessoas comuns sobreviviam no interior de uma cidade de São Paulo em transformação. O autor se relaciona com a micro-história ao considerar aspectos determinantes daquela metodologia, tais como a redução da observação do .
students of Botany at University level, which is organised every year since last 7 years. The Department aims to be a Centre of Excellence. The Department of Biotechnology established in 2002, at present offers UG, PG and Ph.D. programmes in Biotechnology. There are 4 recognized research guides for Ph.D. in Biotechnology and M.Sc. (by research) in Biotechnology. Name of the research centre .
Bribery Podbriefing Audio Transcript 00:03 The Bribery Act is the UK’s anti-corruption law. It introduces a range of offences to tackle corruption, and affects both individuals and organisations, in both the private sector and in public sector context. 00:31 What people often think about bribery is a payment in cash or financial advantage, but a bribe can be many things. It can be excessive .
Calligraphy Learn how to write beautifully and develop your creativity with calligraphy. You will learn fundamental approaches, letterforms, layout and design. Calligraphy can be used to enhance artwork, illustrate writing, create invitations or as a stand-alone art form. Calligraphy - beginners and progression to intermediate
Cold War The Cold War was a period of East-West competition, tension, and conflict short of full-scale war, characterized by mutual perceptions of hostile intention between military-political alliances or blocs. There were real wars, sometimes called "proxy wars" because they were fought by Soviet allies
