Safer Inspection of Medium Voltage Electrical Panels on Navy Ships

Transcription

1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. 1 FY15 NSRP ETP Panel Project Safer Inspection of Medium Voltage Electrical Panels on Navy Ships NSRP ETP Panel Meeting Electrical Panel Meeting, San Diego, CA December 9, 2015 Penn State Electro-Optics Center The Navy Manufacturing Technology Center of Excellence for Electro-Optics 222 Northpointe Blvd. Freeport, PA Jeff Callen Research and Development Engineer Electrical Engineering and Systems Engineering , ext jcallen@eoc.psu.edu Matthew E. DiGioia Engineering Project Manager Assistant to ManTech Program Operations , ext mdigioia@eoc.psu.edu

2 Presentation Outline 1. Project Background Issue & Approach Participants & Stakeholders Technical Approach & Deliverables 2. Status Update Lab Testing Results Milestones 3. Summary Quad / End 4. Backups 2

3 Safer Inspection of Medium Voltage Electrical Panels on Navy Ships Background Even under best practices, installation of shipboard switchboards results in loose connections and wiring mistakes that lead to arc faults and other electrical maladies Average of 8 arc faults per year throughout the navy fleet - all occurred in Switchboards and Load Centers - cost Navy millions of dollars in downtime and repairs [NAVSEA, SUPSHIP Gulf Coast] Newer ships have electrical systems considered medium to high voltage LHD, LHA, DDG-51(FLTIII), DDG-1000 = Medium, 4160 volt systems (CVN = High, 13,800 volt systems) Switchboard Inspections: during construction, builder s trial, during sea trials, and again at regular maintenance intervals Current inspection methods: typically utilize Thermal IR imagers to investigate cabinets and comparatively identify hotspots ; other investigation modes require close proximity interrogation Temperature difference between phases Load Center 3

4 Safer Inspection of Medium Voltage Electrical Panels on Navy Ships Issue Current Inspection Practices: secure the area, personnel don full coverage Personal Protective Equipment (PPE) to image inside active panels, preferably while drawing a high load such as during sea trials. Some facilities will not open panels for inspection on 4160V, even with PPE. Necessitates a new paradigm in switchboard inspection to comply with OSHA regulations and avoid Technical Warrant Holder (TWH) waiver requests Approach EOC s initial analysis identified preliminary requirements and potential solutions for both temporary installations acceptable before and during sea trials as well as permanent solutions which must be compliant with Mil-Specs for shipboard operations Leading candidate solution: temporary or permanent installation of panel covers with IR transparent windows enabling safe IR inspection without exposing personnel to active electrical components Allows inspectors in the room to operate at any time before/during acceptance/sea trials without PPE, while utilizing the same cameras and practices currently used but without the cumbersome and costly need to secure the area and deactivate and reactivate electrical switchboards. Candidate solutions were vetted through NSRP Electrical Technologies Panel (ETP) presentations and subsequent stakeholder interactions. Besides IR windows, potential solutions with pros and cons of each were explored including a standalone gantry for remote imaging, temperature sensitive paint, and RF interrogation of embedded temperature sensors With the support of this community, the approach was refined such that this project focuses on demonstration of temporary (or permanent) installation of panel covers with IR transparent windows enabling safe IR inspection without exposing personnel to energized electrical components New MIL-DTL-32483, dated 8 Nov. 2013, DETAIL SPECIFICATION SWITCHGEAR, POWER, HARD- MOUNTED, MEDIUM VOLTAGE, NAVAL SHIPBOARD, requires use of thermal imaging windows. LHA 8 invokes MIL-DTL for 4160V Switchboards. 4

5 Active Project Participants Lead Investigators Jeff Callen Matthew E. DiGioia Sponsoring Shipyard Jason Farmer Penn State Electro-Optics Center Research and Development Engineer, Electrical Engineering and Systems Engineering Penn State Electro-Optics Center Engineering Project Manager, ManTech Sensors, Robotics, and Automation Ingalls Shipbuilding (Pascagoula) Project Lead / Electrical Engineer IV jcallen@eoc.psu.edu mdigioia@eoc.psu.edu jason.farmer@hii-ingalls.com Government Stakeholder Clay Smith Project Technical Representative Richard Deleo SUPSHIP Gulf Coast Engineering Newport News Shipbuilding Engineering Manager - Submarine Electrical david.smith@supshipgc.navy.mil r.deleo@hii-nns.com 5

6 Integrated Project Team (IPT): Advisors and Other Stakeholders Government Stakeholders Dave Mako NSWC Philadelphia Division, Code 427, Propulsion & Power Systems John Zabita NSWC Philadelphia Division, Code 511, Instrumentation & Sensors (IR Thermography) Industry Advisors Gary Weiss DRS Power & Control Technologies, Inc. Business Development Manager for Power Distribution and Power Conversion John Ykema L3 SPD Electrical Systems, VP and CTO Other Interested Parties Tom Connolly NSWC Philadelphia Division, Code 427, Propulsion & Power Systems Greg Stevens Bath Iron Works Electrical Engineering Dennis Neitzel AVO Training Institute, Inc. OSHA Authorized Maritime Trainer Principal Committee Member, NFPA 70E 6

7 Technical Approach Process and Means to Accomplishing Goals and Objectives (from SOW) Review Shipbuilder/Government/Industry Requirements for IR Panel Inspection and Current Inspection Practices [HII, SSGC & Penn State EOC] Determine Camera(s) and Window(s) to be Used [Penn State EOC Led] Laboratory Tests of Cameras and Windows [Penn State EOC Led] Devise Practical Implementation [Penn State EOC, HII & SSGC] Plan and Prepare for Final Demonstration [Penn State EOC, HII & SSGC] Develop Technology Transition Path Including Safety/Business Case [All] 7

8 Deliverable 6.1 Proof of Concept Demonstration A demonstration of IR thermography through one or more IR windows installed in the door of a 4160V switchgear panel that is representative of the type of switchgear panels to be on LHA-8 and similar vessels. Demonstration for sponsors and IPT ~ late January Originally Targeted LHA-7 Sea Trial (trials scheduled for late Summer 2016 = outside PoP) Now Exploring DRS Milwaukee Facility: Thermography Demonstration in DRS prototype 4160V switchgear panel and testing facility Make main power connections to the panel busbar (two phases minimum, three preferred) Energize panel connections with low voltage, high current to simulate properly operating panel (temperatures of phases approximately equal and typical of full load temperatures) IR thermography imaging through IR windows mounted in panel cover. Window and camera placement such that viewing can be done around internal obstructions in the cabinet. Thermography Demonstration with Simulated Fault Simulate a potential bad connection by altering the test conditions so that one phase connection is significantly higher temperature than another phase. Repeat IR thermography through Windows Assistance in fabricating a panel door cover modified with IR windows(s) DRS and EOC jointly determine location of two IR windows such that imaging of main bus connections can be done through the windows, taking internal obstructions (structure, phenolics, other cables) into account. EOC supplies DRS with two IR windows DRS supplies a surrogate cover for the panel and installs the window(s) in the predetermined cover locations 8

9 Reporting Deliverables 6.2 Quarterly Reports: April, July, and October Report Outline: (1) Project Overview (2) Technical Status (3) Schedule, (4) Business Status (5) Issues (6) Near-Term Plans 6.3 Final Project Report Final report content shall summarize research done, test methodology, test results, demonstration results, and technology transition path forward 9

10 Project Update IR Windows Crystal vs. Polymer Crystal Windows Pro: Vis and IR, no reinforcement grid. Con: possibly could deteriorate over time (reviewing this issue), transmission cuts off midway through long IR band Polymer Windows Pro: no deterioration, full IR band, some rectangular Con: Need reinforcing grid, some will not pass vis light (need separate window) Cameras and IR Windows Cameras FLIR EX320 from SUPSHIP-GC Fluke TI32 from Ingalls FLIR T440 borrowed from FLIR Windows FLIR IRW-4S: 4 round crystal (matches LHA-8 spec) Fluke CLirVu CV400: 4 round as a 2nd crystal window Exiscan XIR-A-4-H-X: 4 square polymer window IRISS VPT-100: 4 round as a second polymer window Laboratory Testing Tested both polymer and crystal windows, plus multiple cameras Established basic performance: accuracy with and without windows, temperature range, Field of View, visible transmission, view actual cable with lugs and simulated temperatures 10

11 Laboratory Test Results - 1 Cameras FLIR EX320 from SUPSHIPS not used FLIR T440 Fluke TI32 4 Windows (covers removed) FLIR IRW-4S Fluke CV400 IRISS VPT-100 Exiscan XIR-A-4-H-X 11

12 Laboratory Test Results - 2 Test Setup Camera, windows and targets fastened to fixtures on optical table for repeatability For most tests, target was CI Systems model SR-80 blackbody radiation source (20 C to 87 C). 7 by 7 radiation face (emissivity = 0.97) Windows clamped to fixture for quick interchangeability. Window 18 from target, camera 1 from window. Camera mounted Blackbody Controller Window Fixture Blackbody Head FLIR IRW-4S window with T440 Camera 12

13 Laboratory Test Results - 3 Camera Tests FLIR T440 and Fluke TI32 tested without windows at three temperatures. FLIR EX320 not tested. RESULTS: Differences between cameras were minor and both were judged to have performed essentially the same without windows. Window Comparison All four windows tested with both cameras at two temperatures. Reading without window taken, then with window installed, transmissivity of camera adjusted so that temperature was same as that without window. RESULTS: Accurate measurements were made with both window types. Transmissivity settings indicate more attenuation in the crystal windows. The two crystal windows are virtually identical to each other. The reinforcing grids on the polymer windows were evident in the images and affected temperature readings slightly. Small variation (a few percent) in transmissivity settings between cameras and between tests. 13

14 Laboratory Test Results - 4 Horizontal and Vertical Field of View (T440 Camera/FLIR and IRISS Windows) Blackbody source masked for a more realistic target. Camera fixed in place and target moved left and right until reading no longer possible. Distances measured and angle calculated for maximum horizontal field of view. Camera and mask rotated 90. Test repeated for vertical field of view. Camera has a standard lens which has an HFOV of 25 and a VFOV of 19. Thermal Image of target mask size and shape of connection lug Camera and target mask rotated for vertical field of view test 14

15 Laboratory Test Results - 5 Horizontal and Vertical Field of View Results Horizontal and vertical field of view through both windows was very large span width and most of height of representative cabinets. Camera positioned and angled for best view Temperatures dropped at far extreme angles for both windows (more material at shallow angle) Drop off more severe for polymer window (more of reinforcing grid) Window HFOV VFOV Temp drop at extreme edge Crystal (FLIR) % Polymer (IRISS) % Digital image through polymer window at shallow angle 15

16 Laboratory Test Results - 6 Simulated Fault, with cable and lugs Two samples of representative T400 cable with connecting lugs bolted to copper bus bar with 500 W power resistor mounted to the rear. Temperatures of the two lugs set to different values by running a different current through each resistor as a heater. Stabilizes in about 1 hour. Images taken with no windows and with the crystal window and the polymer window Cables and Lugs on bus bars Rear view, power resistors as heaters Black tape for setting camera emissivity (bus bar and lugs stabilize at same temperature). Measure temperature on tape with emissivity set high (0.95). Set emissivity for lugs to obtain same temperature. 16

17 Laboratory Test Results - 7 Simulated Fault, with cable and lugs - Results Temperatures varied considerably highly sensitive to placement of measurement spot (surface variations). More repeatable with measurement box. Navy compensates for variations by mandating an emissivity setting of 0.8, rather than have each operator estimate the setting. Tests done at different times and by different operators can be compared. Comparison between electrical phases more important than absolute temperatures. With emissivity at 0.8, readings through crystal window are a little high for the upper temperature, and readings through polymer window are a little low. Transmissivity settings taken from previous tests and result in slight differences in readings. TAKEAWAY: As the Navy does for emissivity settings, a practical test will need to establish proper transmissivity settings to result in a test that errs on the side of safety while allowing comparative tests. 17

18 Laboratory Test Results - 8 Rubber Dust Boot Not strictly an IR Window issue, use of rubber dust boots over the bus bar connections will affect the thermography. Rubber (exact material unknown) boots are placed over bus bar connections to reduce the clearance distances required to avoid arcing, tracking and electrical creep. Sample boot tested with cable and lugs test setup. Installation jury rigged (not same geometry) to cover lugs and be enclosed. Some air gaps remained. Two lugs were heated until about 34 C apart then allowed to stabilize over 3-4 hours to allow heat to build up underneath the boot. No windows. Measurements at multiple points Camera distance 27 for more in field of view. Emissivity 0.95 based on tests with the boot material. 18

19 Laboratory Test Results - 9 Rubber Dust Boot Results Hot spots in various locations small air gap or touching. Max temperatures about 20 C lower than temperature of the lug beneath it. Despite ill fitting boot on test setup, still a noticeable difference between hotter and cooler sides. Also measured cable temperatures below the boot - temperature difference 35 C between lugs and about 20 C between cables. Repeated test with crystal window with identical results. Definitive quantitative data not possible from this test, as fit of boot allowed large air gaps in places. Sufficient differences between hot spots on boots or cables to indicate one connection is significantly hotter than adjacent connection. 19

20 Laboratory Test Results - 10 Visible Imaging Visible images put thermal image in context to identify location. Thermal imagers have visible camera and lamp built in. Visible images taken through both crystal and polymer windows. Two issues were evident. Crystal window provided no obstruction to the image. Polymer window, though clear, has reinforcement grid. Grid does not affect thermal image significantly, but is present in the visible image. Reflection off the window face when illuminated by camera lamp. Imaging through windows will have cabinet cover closed, and no internal illumination. Glare is worse on the polymer window reinforcing grid. Images can be taken through polymer reinforcement grid, but requires careful camera positioning May be necessary to use another illumination source - same window or another location to illuminate the target area. 20

21 Laboratory Test Results - Conclusions These tests established baseline on how windows affect measurements and provided insight on impacts to shipboard thermography inspections. Environmental tests on windows outside project scope. Conclusions: 1. Reasonably accurate temperature measurements can be made through IR windows provided attention is paid to emissivity and transmissivity settings in the camera. 2. Variations in emissivity and transmissivity will need to be minimized by developing uniform techniques and procedures to provide a useful comparison test, as is done presently with emissivity settings. 3. Windows allow wide enough field of view that number and placement of windows in the cabinet will be limited only by the internal obstructions and line of sight views. 4. Polymer window reinforcement grids affect thermal measurements slightly, but also affect the field of view and make visible imaging difficult. 5. Rubber dust boots do affect the absolute thermal measurements. Hot spots will show up on the boot or cable, but it was not possible to quantify the differences properly. More study is needed. 6. Reflected glare indicates that for visible imaging in a closed cabinet, some other illumination source will be needed, either through the same window or through some opening. 21

22 Safer Inspection of Medium Voltage Electrical Panels on Navy Ships Summary Milestones (NCE Pending) 1/19/15: Contract awarded to EOC 2/11/15: Kickoff Meeting HII 4/10/15: Quarterly Report #1 4/16/15 (Thur): 1st Telecon (review requirements & camera selections, Quarterly Report #1) 6/10/15: Technology Interchange Meeting (Concurrent with Summer ETP Meeting) Discuss the results of initial research into suitable IR inspection window(s) and camera(s) Identify a candidate system for testing and demonstration with preliminary test plans conveyed The outcome of this meeting will be agreement to proceed with procuring equipment & materials Jul 2015: Quarterly Report #2 Aug 2015: 2nd Telecon (review finalized lab experiments & plans) Oct 2015: Quarterly Report #3 Oct 2015: Technology Interchange EOC (was 3rd Telecon ) Review lab results and discuss practical implementation plans Jan 2016: 4th Telecon (finalize plans for demo) Jan/Feb 2016: Demonstration (@DRS) Mar 2016: Draft of Final Report (w/ Transition Path Developed) Delivered (in advance of Final Review) Mar 2016: Final Review Meeting (Telecon) [Deliverable] Apr 2016: Update & Deliver Final Report [Deliverable] 4/20/16: End of EOC Period of Performance (NCE Pending) 22

23 Safer Inspection of Medium Voltage Electrical Panels on Navy Ships Sponsor: The National Shipbuilding Research Program 2014 Electrical Technologies Panel Project Average of 8 arc faults per year throughout the navy fleet - all occurred in Switchboards and Load Centers can result in serious injury and costs Navy millions of dollars in downtime and repairs Current Inspection Practices: secure the area, personnel don full coverage Personal Protective Equipment to image inside active panels, preferably while drawing a high load such as during sea trials. Tasks/Achievements: Leverage the current state of the art in industry and the recently revised NFPA 70E criteria (National Electrical Code, Standard for Electrical Safety in the Workplace ); emphasizes substantial risk reduction for workplace injuries and fatalities due to shock, electrocution, arc flash, and arc blast Review Shipbuilder/Government/Industry Requirements for IR Panel Inspection and Current Inspection Practices Laboratory Experimentation with Cameras and Windows Plan and Execute Final Demonstration of Practical / Representative scenario on a Navy ship Develop Technology Transition Path Including Safety/Business Case Deliverables: Quarterly Reports: April, July, and October Proof of Concept Demonstration: representative IR thermographic inspection using an IR window in closed electrical panel cover Final Project Report: Jan-16 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Objective: Develop safer, cost effective solution within existing thermographic inspection practices for onboard medium/high voltage electrical infrastructures: utilize IR transparent viewports in electrical panel covers to reduce risk for government and shipbuilders Performing Activities: Jan 2015 Jan 2016, $150K Penn State Electro-Optics Center Ingalls Shipbuilding SUPSHIP Gulf Coast Newport News Shipbuilding Integrated Product Team Includes: NAVSEA (TWH Office), Naval Surface Warfare Center Philadelphia Division, OSHA Safety Trainer, Industry Product Supplier Implementation: System: Medium & High Voltage Electrical Infrastructures on Navy Platforms (LHD, LHA, CVN ) Site: Schedule: Status: LHA-7 SUPSHIP-GC (Proof of Concept Demo - Future) Jan 2016 = Demo Results with Transition Plan for Temporary Installations Intend future Insertion / adoption Benefits / Payoff: Reduced safety risk to personnel: enables safer practices within existing inspection methods and procedures Potential to provide inspection process cost savings Applicable across multiple military domains & platforms with Information shareable across shipbuilder industry 23 NOV15

24 BACKUPS 24

25 Safer Inspection of Medium Voltage Electrical Panels on Navy Ships Project Goals and Objectives The suitability and the safety impact of using IR windows in electrical panels for thermographic inspection of electrical connections on Navy ships will be determined 1. Develop safer, cost effective solutions with IR transparent viewports in electrical panel covers to reduce risk for government and shipbuilder inspection of onboard medium/high voltage electrical infrastructures Facilitate comprehensive inspections accomplished with less risk and reduced labor Eliminate or reduce the need for secured locations, personal protective equipment (PPE), and waiver requests wrt OSHA standards 2. Develop and demonstrate a proof of concept solution that meets temporary (or permanent) installation requirements for the shipbuilder/government implementers Utilize principal methods and practices currently employed but without the cumbersome and costly need to secure the area and deactivate and reactivate electrical switchboards Inspections made with closed panels avoiding dangerous proximity to energized circuits Allow inspectors in the room to operate at any time before/during acceptance/sea trials 3. Establish the business / safety case and path to implementation for government and shipbuilder applications Develop the business case and risk reduction benefits for shipbuilder construction and government applications where inspection of electric switchboards, load centers, and transformers is necessary Pursue industry support and buy-in with identification of vendors which can provide products that meet temporary installation requirements Explore the criteria and viability for permanent installations within MIL-DTL (RevA pending) 25

26 Project Assumptions V panel from LHA7 examined at HII on 2/11/15 will be considered as representative of the inspection to be solved. This type of panel will be used for the project demonstration. 2. Target conditions for final demonstration will be to take thermal images on one energized LHA7 panel in situ on the ship. Intentional faults will be excluded for safety reasons. Scheduling and logistical concerns may preclude this scenario and if so, alternative conditions will be developed and agreed upon by the IPT. 3. While all electrical connections within the cabinet are important for inspection, SUPSHIPS is most interested in the connections made at the shipyard to the cabinet. Specifically, this includes the feed cables at the bottom level of the cabinet and at the middle level of the cabinet. The connections to the fuses at middle and top and the transformers behind the fuses will be considered but with lower priority than the feed cables. 4. Broadband windows will be required such that IR and visible inspection can be completed through the same viewing port. 5. IR windows used will have metal covers over them to secure the integrity of the panel cover when window is not in use. 6. HII and GCSS will be able to loan IR cameras for thermal inspection to Penn State EOC subject to scheduling constraints. 7. Depending on viewing angle and cabinet construction, multiple smaller windows may be desirable rather than fewer large windows. 8. Windows and other materials used in the testing and demonstration will need to meet MIL-STD 901D Grade B shock and vibration, or that a path forward to attain this standard can be developed. 9. Field of View and off angle viewing will permit much more area within the cabinet to be viewed by the camera than the space directly behind the window. 26

27 Project Requirements 1. Relevant delta temperature values for pass/fail inspection of 4160V panels or guidelines as to what temperature delta will make a relevant demonstration. 2. Dimensional drawings of the target demonstration panel, so realistic laboratory tests can be developed. 3. Samples or part numbers of dust cover boots used in the target 4160 panel. If not available, then representative material. 4. Samples of cables with lugs that are used for connecting to the target 4160 panel. 5. List of IR thermography cameras currently used or planned to be used for inspections (Fluke TI-32, FLIR EX320, possible FLIR T400) 6. If possible, supply of an actual panel cover for the target 4160V cabinet that can be modified for installation of IR windows to use in the demonstration. 27

28 Camera Compare 28

29 Window Compare No. LHA-8 Spec FLIR IRW Series FLIR IRW S* Exiscan XIR-A- 4-H-X Exiscan XIR-A- 3-H-X Exiscan XIR-S- Fluke CLirVu Fluke CLKT IRISS VPFC IRISS VPT 4-H-X 1 Permanently attached cover Y Y Y Y Y Y N Y Y 2 Single hole installation Y Y No, 8 bolts No, 8 bolts No, 8 bolts Y 3 self tap screws???? 3 standard hole punch install Y Y Saw or punch Saw or punch Saw or punch Y Y???? 4 Solid metal cover Y Y Y Y Y Probably Probably Y Y 5 No tools to open window single thumbscrew single thumbscrew 4 hex head captive screws 4 hex head captive screws 4 hex head captive screws 1/4 turn hand turn captive Hex head screw Phillips screw Phillips screw 6 Broadband (vis and thermal) Y Y No, separate window for vis No, separate window for vis No, separate window for vis Y Y Y Y 7 No obstructions, including reinforcing screens Y Y Diamond reinforcing screen Diamond reinforcing screen Diamond reinforcing screen Y Y Y Hex reinforcing screen 8 Rated to 250 C 260 C 260 C 150 C 150 C 150 C 232 C & 260 C intermittent 9 Stainless Steel housing Anodized Alum. 316 Stainless Stl anodized Alum, pwdr coat anodized Alum, pwdr coat Stainless "high strength alloys" 250 C 200 C 200 C Aluminum Nylon Nylon, SS cover 10 Pull out strength 3600 lbs. 2" 1450 lb. 3" 3650 lb. 4" 3700 lb. 2" 1450 lb. 3" 3650 lb. 4" 3700 lb. No Spec No Spec No Spec No spec 1388 lb. No Spec No Spec 11 Rated low, med, high voltage Y Y Y Y Y Y Y???? 12 Meet UL 50V Y Y Y Y Y Y? Y Y 13 Meet UL50 Environ. Type 4/12 4/12 4/ /12 3/ Meet KEMA (IEC ) Arc flash 5kV, 63 ka 30 cycles 60 Hz. 5 kv, 63 ka 30 cycles 60 Hz 5 kv, 63 ka 30 cycles 60 Hz ANSI/IEEE C ANSI/IEEE C ANSI/IEEE C37 63 ka 30 cycles Hz, meets C C ka for 30 cycles 60 Hz?? C ka, 15 kv for 30 cycles 60 Hz 15 Meet TUV (IEC 60529) IP67 IP 67 IP 67 IP65 IP65 IP65 IP67 IP65 IP65 IP65 16 Meet TUV (IEC 60068) 100 m/s 2 IEC IEC ???? vibration 100 m/s m/s 2 No Spec vibration "unaffected" No Spec vibration "unaffected" No Spec vibration "unaffected" 17 Meet TUV (IEC ^ ) 15 day Y Y Humidity & extreme humidity moisture "unaffected" Humidity & moisture "unaffected" Humidity & moisture "unaffected" IEC IEC ???? 18 Optic Material Calcium Fluoride Calcium Fluoride Polymer Polymer Polymer Crystal Crystal Calcium Fluoride Polymer 29

30 Master Integrated Schedule (v.6/2/15) 30

31 Other Solution Concepts IR Fibers for Blackbody Radiation [NNS via Deleo] IR Fibers for Blackbody Radiation 1. One potential avenue is to use IR fibers to transmit blackbody radiation to a high density FO connector on the face of the panel. 2. Connector can then be read by a variety of methods. Can even develop a special tool to automate scanning. 3. This allows a high level of flexibility with regard to mapping the inside of a panel and monitoring areas without a direct line of sight. 4. You can also easily accommodate a large number of measurements without a significant impact to the panel face (just a connector and dust cap). Pro s: 1. Non-conductive materials eliminate short circuit potential 2. No EMI concerns 3. Not a tactical concern (failure or loss doesn t degrade performance of equipment) 4. Flexible and can be added easily to a design with minimal risk to military qualifications 5. Field installable 6. Lends itself to automation in the future 7. Simple installation. Fibers are not required to carry data so precision installation not an issue. Large light loss acceptable. You only need enough to measure radiation frequency to determine temperature. 8. High quality FO conductors exist 9. High quality (and Mil Spec) connectors exist (Mil-DTl-38999) at high densities (e.g. 64 conductors in small footprint) Con s: 1. Not consistent with current inspection practices 2. Expensive / impractical retrofit? 31

32 Other Solution Concepts Embedded Temperature Sensor & Camera [via Mako & Smith] FLIR AX8TM Combining thermal and visual cameras in a small, affordable package, the AX8 provides continuous temperature monitoring and alarming for uninterrupted condition monitoring of critical electrical and mechanical equipment. 1. The AX8 provides early detection of temperature-related issues in electrical and mechanical equipment, making it the ideal temperature sensor for continuous condition monitoring and hot spot detection for electrical cabinets, process and manufacturing settings, data centers, mass transit facilities, energy generation plants, and storage facilities. 2. Easy to install in electrical cabinets or other confined areas, the AX8 provides uninterrupted condition monitoring of critical electrical and mechanical equipment to help reduce unplanned downtime and prevent safety hazards. 3. Learn more about this powerful thermal sensor and camera, and its many practical applications: Pro s: 1. Continuous condition monitoring 24/7 2. Excellent solution for new construction (pending cost/safety benefit) Con s 1. Not consistent with current inspection practices 2. Expensive / impractical retrofit? Pending Further Investigation 32

33 Results of Initial Trade Study EOC s initial analysis identified preliminary requirements and potential solutions for both temporary installations acceptable before and during sea trials as well as permanent solutions which must be compliant with Mil-Specs for shipboard operations Leading candidate solution: temporary or permanent installation of panel covers with IR transparent windows enabling safe IR inspection without exposing personnel to active electrical components This would allow inspectors in the room to operate at any time before/during acceptance/sea trials without PPE, while utilizing the same cameras and practices currently used but without the cumbersome and costly need to secure the area and deactivate and reactivate electrical switchboards. Besides IR windows, potential solutions with pros and cons of each were identified including: Curtain RF interrogation of embedded temperature sensors A standalone gantry for remote imaging temperature sensitive paint Candidate solutions were vetted through NSRP Electrical Technologies Panel (ETP) presentations and subsequent stakeholder interactions With the support of this community, the approach was refined such that this project focuses on demonstration of temporary (or permanent) installation of panel covers with IR transparent windows enabling safe IR inspection without exposing personnel to energized electrical components 33

34 Initial Trade Study Solution Concepts Panel with IR Transparent Windows (Temporary or Permanent) Replace panel with a temporary panel that has IR transparent windows in it. 1. Windows would be small to keep costs down. 2. Multiple windows would supply the required angles and fields of view. 3. Small panels, some of each with windows, can be modular. 4. An entire panel might consist of 9 subpanels, of which 3 or 4 would have windows. 5. The subpanels would be reconfigured to match the best viewing angles for the switchboard that is being inspected. 6. Some of the windows could be in angled conical mounts so as to direct the FOV somewhat off of normal. 7. Rotating conical mounts like this would allow this angle to be aimed in any direction. 8. The power would be shut off while the regular panel is removed and this temporary panel takes its place. Power restored then inspection takes place same as the old inspection. 9. Temporary panel removed and taken to next switch panel. 10. Temporary panel can be reconfigured if necessary. Pro s: 1. Allows inspectors in room, permitting inspection at any time, including underway 2. Inspection can be done with same cameras and techniques used now. Con s: 1. Requires temporary shutdown of panel while temporary panel installed or removed. 2. Geometry dependent. Even with modular subpanels, might be difficult to get the best location and best angles for meaningful test. 3. Unclear whether one size will fit all. May need more than one set, or some adaptor to make it fit on different size panels. Other Issues / Determinations: 1. Wide array of LWIR transparent windows materials: ideal would be one that has high visible (~ 80%) and IR (>60%) transmission, large/standard size, and durability to withstand a flash event (not be blown out or melt). Cost implications 2. Could use separate IR/Vis windows unless it is possible to take the vis pictures after the inspection is over and the panel is shutdown for removal of our temporary panel 34

35 Initial Trade Study Solution Concepts Curtains - Subset of Panel with IR Transparent Windows Curtains (subset of Panel with IR Transparent Windows): Instead of panel with conical camera ports, create a curtain with a port in the middle. 1. Curtain would resist spark and flame, like welding curtains. 2. Can make it from same material as the flash protection suits. 3. Curtain could be sewn so as to form pyramidal or conical general shape. 4. Curtain flexible enough to allow camera to be moved around to exact position and angle desired. If looking through camera lens, no window in curtain will be needed, just a hole to poke the camera through. 5. Camera may need lights for the visible pictures. Pro s: 1. Simpler than panel 2. More flexible in positioning camera 3. No IR window needed 4. Not very expensive Con s: 1. Not sure welding curtain type cloth will be acceptable. (flash protection suit material should be acceptable) 2. May be unwieldy to move camera surrounded by thick curtain 35

36 Initial Trade Study Solution Concepts Temp Sensor w/rfid Interrogation Temp Sensor w/rfid Interrogation 1. Researched commercially available: see below, - Temp Sensor w/rfid Interrogation 2. Use a contact temperature sensor with RFID-like (wireless) interrogation. Pro s: 1. No change to existing panels 2. No camera required to inspect documentation with auto logging of sensor serial #/location 3. Gather data when convenient. Panels operated normally no open panels, no personnel safety issues. 4. Geometry independent camera same angles as with present inspection Con s 1. Requires additional steps to add and remove sensors and create database of sensor locations 2. Unknowns/Issues: 3. EMI interference with panel closed when trying to read? Unlikely but Need more research 4. Cost? 5. Perhaps make a permanent installation? 6. Variation: has a product called Delta T Alert, which is a wireless device you put on the door and it monitors temperature inside the cabinet vs. outside, and logs data at regular intervals. Can set up a network of these. Only measures entire cabinet temperature, but one testimonial credited it with alerting him to a phase unbalance in one of his cabinets. Perhaps part of the long term solution. 36

37 Initial Trade Study Solution Concepts Remote Operated Camera Gantry System Standalone Gantry with PTU 1. Build a man-high frame with a motorized X-Y gantry on it. On the gantry, mount the camera on a PTU. 2. Shut down the switchgear, remove the panels, set up the frame where a person would stand to do the inspection. 3. Gantry and PTU permit the camera to be placed anywhere a person would place it. Control everything remotely. 4. When inspection finished, shut down power remotely, replace panels and move on. Pro s: 1. Can get all of the viewing angles that are currently available. 2. Probably simplest to implement (X-Y and PTU do not need to be of any great precision) 3. Costs are low, depending on the camera Con: 1. Need a camera that can be operated remotely 2. Probably will be wired, so will need to see what safety issues there are running cables out of the room. 3. Bulkiest of the potential solutions. 4. Requires people to be out of room, so would be difficult to implement while underway. Subset (Gantry with PTU inside panel box) 1. Reproduce the XY gantry with PTU in a box that hangs on the switchgear in place of the regular front panel. Shut down panel, remove front, replace with this box, re-energize and do inspection. Pro: 1. Panel is closed so inspection can be done with people in room and done at any time. 2. Fairly low cost XY gantry and PTU do not need to be of great precision Con s: 1. Of necessity will have camera fairly close to panel. FOV and focus might be problematic that close Camera might be bulky 2. Difficult if panels are significantly different in size 3. Projection from panel might be an issue. 4. Need remotely operated camera 37

38 Initial Trade Study Solution Concepts Temperature Sensitive Paint Temperature Sensitive Paint There are paints that change color depending on their temperature (thermochromic). There are both irreversible (which stay at the color they changed to at their highest temperature) and reversible (which change back to their original color when the temperature returns). In the case of irreversible, it is often a change in density of the same color, so the color darkens. They could be incorporated in the following manner: Subset (Irreversible Thermochromic Paint) The paint can be applied on assembly or prior to inspection to the potential hotspots (terminals on cables, studs on panels). If desirable not to introduce paint to the components, pads can be constructed with the thermochromic paint on the top and an adhesive backing. Prior to inspection, these pads can be applied to the potential hotspots. After the panel is powered up, then shut down, the cabinet doors are opened and the colors on the pads examined. Those that were hotter will have darker or different color than their neighbors in the same circuit. Comparison color charts can be made up that can be held against the pad in the panel to judge a maximum temperature reached. Photos can be taken with visible light color camera. Pro s: 1. No change to existing panels 2. No camera required to inspect documentation with a visible camera only 3. Panels operated normally no open panels, no personnel safety issues. 4. Geometry independent camera same angles as with present inspection Con: 1. Will change color only when absolute temperature exceeds threshold. A bad connection may not indicate at less than full current (lower temp). 2. Requires additional steps to add and remove pads 3. Temperature sensitivity may not have fine enough resolution to tell difference between a few C. (ACTION) Need more research. 4. Need to have the pads made up. 5. If paint applied directly, then would need to pass approval to be permanently installed inside the cabinet. Also, would need to be stripped off and reapplied for each retest. 6. Requires shutdown of panel both before (to install the pads) and after (to read the results) Subset (Reversible Thermochromic Paint) The paint can be applied on assembly or prior to inspection to the potential hotspots, either directly, or via the pads described above. Panel replaced with temporary panel containing visible transmission windows. Inspection done while panel energized and color change is noted by comparing color of different phases of the same circuit. Done with visible camera for inspection or just documentation. Pro s: 1. No camera required to inspect documentation with a visible camera only 2. Much more flexibility in obtaining appropriate visible windows than IR windows. 3. Transmission much higher through visible windows (closer to 100 %). 4. Less geometry dependent visible windows can be larger to cover more angles than IR Con s: 1. Will change color only when absolute temperature exceeds threshold. A bad connection may not indicate at less than full current (lower temp). 2. Requires additional steps to add and remove pads 3. Temperature sensitivity may not have fine enough resolution to tell difference between a few C. Need more research. 4. Requires temporary shutdown of panel while temporary panel installed or removed. May not be able to open panel quickly enough to catch change 38

39 Initial Trade Study Solution Concepts Other Ideas Considered but Not Explored in Initial Trade Study Flexible Camera Head Through Louvers (borescope) 1. IR camera with imaging head on gooseneck, probably (non-conductive) fiber optic. 2. Insert camera head through louvers in existing panel while switchpanel is energized. 3. Move camera head around via gooseneck, or attached to insulating rod or other manipulating device. 4. Move to different louvers to get best view. Pro s: 1. No change in existing panels 2. No requirement to shut panels off while equipment is installed or removed. 3. Test can be done at any time, including while ship is underway Con s: 1. Highly geometry dependent. Doubtful that all relevant views can be obtained through louvers. Unclear if required manipulation can be done through louvers. 2. Requires penetration of plane of panel Potential safety issue, even if camera head is isolated Embedded Camera Ports (Subset to Temporary Panel/Curtain) 1. Instead of IR windows, have subpanels with camera ports, probably conical to the outside of the panel. 2. Camera goes at peak of cone, but has ability to be angled in pan and tilt. Inside of cone has mechanical shutter. 3. Panel is installed in place of regular panel. All shutters are closed. 4. Camera is installed in one port, and then shutter is opened. 5. Camera angled for best view and test performed. Shutter closed and camera moved to next port. Pro s: 1. Less expensive than multiple IR windows Con s: 1. May not get all the angles needed with camera fixed at end of cone 2. Possible mechanical challenge to allow PT at port while still protecting from HV discharge within 39

40 Laboratory Test Results - 4 Downselect Though the two cameras were both adequate for the measurements, further testing was down only with the FLIR T440. This camera was selected for its feature set and it is representative of the cameras used by the Navy. The FLIR and Fluke crystal windows were virtually identical in performance but the FLIR was chosen as being closest to the preliminary specifications for LHA-8. The Exiscan polymer window was set aside as it is translucent to visible light and would preclude taking visible images. Also it was hard to focus the IR image through it. The IRISS polymer was used in subsequent tests. Range Test The FLIR and IRISS windows were tested with the blackbody set to 25 C, 35 C, 45 C, 55 C, 65 C, 75 C and 85 C. RESULTS: Accurate readings could be made with both windows of the full temperature range provided transmissivity was set appropriately. Some slight variation of transmissivity setting was seen (a couple of percent) to get the readings to match the no window temperature across the range. The largest deviation was at 25 C, but the blackbody source is not as reliable when set near the ambient temperature. 40

41 Laboratory Test Results - 6 Simulated Fault Two blackbody radiation sources were placed side by side and their faces masked with black tape to leave an area on each the size and shape of a connection lug. The back bodies were set to different temperatures and measurements were taken with both windows at temperature differences between the two sources of 5 C, 20 C, 40 C, 50 C and 60 C. Camera transmissivity settings were taken from previous tests with these same two windows. Thermal image of two targets 20 C apart, through crystal window Results Differences between the two windows was small. Measured temperatures were within 2-3 C of each other for the same measurement when using either window. There is some sensitivity to the transmissivity setting, as was seen in earlier tests, affecting readings by a few degrees. 41