Multi Cable Transit Devices: Applications & Design Methods, PCIC Middle East Feb. 2014

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Summary presentation from a white paper delivered to PCIC Middle East February 2014, introducing engineering design methods for cable transit devices (MCT's), best practices for use of these solutions and engineering work process.

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Multi Cable Transit Devices: Applications & Design Methods, PCIC Middle East Feb. 2014

  1. 1. Multi Cable Transit Devices: Applications and Design Methods Allen Gibson, Roxtec Group Bo Millevik, Roxtec Group Alan Bozek, EngWorks, Inc.
  2. 2. PCIC MIDDLE-EAST 20142 Summary • Introduction - Background • Critical components, configurations and proper sizing of cable transits • Protection, ratings & benefits • Applications • Comparing field-based decisions to proven engineering methods • Checkpoints - Specifications for cable entries • Checkpoints – QA / QC for MCT installations • Conclusion
  3. 3. PCIC MIDDLE-EAST 20143 Introduction • Multi cable transit (MCT) devices commercialized since 1950’s • Original designs to prevent water and fire passage within submarines and marine vessels • MCT devices accepted as standard design and safety practice through most marine and offshore oil/gas applications − DNV, ABS, USCG, Lloyds, etc. • Today = Transferring the knowledge from marine/offshore to land-based industrial applications 3.7.5 cable transit device an entry device, intended for one or more cables, with a seal made up of one or more separate elastomeric modules or parts of modules (modular internal seal), which are compressed together when the device is assembled and mounted as intended. NOTE Cable transit devices can also serve as Ex blanking Elements when the elastomeric modules provided allow for this function.
  4. 4. PCIC MIDDLE-EAST 20144 Multi Cable Transits – Simply Stated • Best value when used for high cable density when more than one demand is present − Fire+IP − Blast +rodent − Vapor tight + blast − Etc. • When maintenance, expansion or future access for cables or pipes will be required
  5. 5. PCIC MIDDLE-EAST 20145 MCT Devices – Critical Components • Frame (window) • Modules (inserts) − Fixed diameter − Adaptable layers with core − Insert blocks • Stay plates (dividers) • Compression (wedge or unit)
  6. 6. PCIC MIDDLE-EAST 20146 Applications – Walls & Floors
  7. 7. PCIC MIDDLE-EAST 20147 Applications – Terminal / Junction Boxes
  8. 8. PCIC MIDDLE-EAST 20148 Applications – Pre Terminated Connectors
  9. 9. PCIC MIDDLE-EAST 20149 MCT Devices – Configurations • Flanged • Non-flanged • Multiple windows – vertical • Multiple windows – horizontal • Combination • Proper framing of aperture is critical
  10. 10. PCIC MIDDLE-EAST 201410 MCT Devices – Sizing / Packing Space • Early engineering decisions = project savings • Get the aperture size correct… FIRST • Consider spare capacity for future expansions and upgrades • Communicate aperture size requirements to civil design and building contractors…BEFORE construction begins
  11. 11. PCIC MIDDLE-EAST 201411 Protection: Environmental (IP) • Most standard MCT designs should have a minimum water tight and dust tight rating equivalent to an Ingress Protection (IP) rating for electrical enclosures of IP 54 as defined by IEC 60529. • Wall / floor applications for MCT’s should be defined by the environmental performance requirements of the structure
  12. 12. PCIC MIDDLE-EAST 201412 Protection: Blast • Blast rating EX, ATEX or HazLoc approval • Cable entries must be considered in design of blast-rated structures, just as doors and windows • MCT devices are commonly available to provide protection against blast load to >10 psi for > 60 milliseconds.
  13. 13. PCIC MIDDLE-EAST 201413 Protection: Vapor-tight barrier • Definition – “a barrier that will not allow the passage of significant quantities of gas or vapor at atmospheric pressure” API RP 500/505 • Effective way of locating non-hazardous rated equipment adjacent hazardous areas
  14. 14. PCIC MIDDLE-EAST 201414 Protection: Vapor-tight barrier An unclassified room or building may be installed adjacent to a classified area provided a vapor-tight barrier is placed between the hazardous location and the unclassified area. •Benefits − Reduce on-site wiring costs − Allows equipment to be pre- commissioned
  15. 15. PCIC MIDDLE-EAST 201415 Protection: Hazardous locations • Cable transit devices are recognized and approved for use according to IEC 60079-0 • MCT devices used in electrical equipment within hazardous locations MUST be properly certified and labeled 3.7.5 cable transit device an entry device, intended for one or more cables, with a seal made up of one or more separate elastomeric modules or parts of modules (modular internal seal), which are compressed together when the device is assembled and mounted as intended. NOTE Cable transit devices can also serve as Ex blanking Elements when the elastomeric modules provided allow for this function.
  16. 16. PCIC MIDDLE-EAST 201416 Protection: Earthing, bonding & EMC «EMC, ElectroMagnetic Compatibility » •Cable segregation •Single Entry Panel
  17. 17. PCIC MIDDLE-EAST 201417 Protection: Earthing, bonding & EMC « Metallic layers inside cables should be connected to earth » •Electrical safety − Protective Earthing − Equipotential Bonding •Lightning Protection •Electro Magnetic Interference (EMI)
  18. 18. PCIC MIDDLE-EAST 201418 Protection: Earthing, bonding & EMC
  19. 19. PCIC MIDDLE-EAST 201419 Protection: Fire Barrier • MCT’s can provide 30 minute to 4 hour protection as a passive fire barrier • Jet fire, A60, H60, UL1479 and more • Some fire rated installations require installation of mineral wool insulation to comply with certifications
  20. 20. PCIC MIDDLE-EAST 201420 Protection: Fire Barrier
  21. 21. PCIC MIDDLE-EAST 201421 Protection: Rodents, Pests, Snakes… “Have you experienced accidents, downtime or damage from mice, rats, insects, snakes, etc. in your motor control, switch gear or other electrical cabinets?”
  22. 22. PCIC MIDDLE-EAST 201422 Protection: Rodents, Insects & Snakes “I've spent quite a few years fixing communications equipment contaminated by ants or dead lizards. Some years ago I had to fix some Optical Fibre equipment where mice had bitten through the fibre to either the transmitter or the receiver; as well as fouling the PCB assembly.” Electrical Project Engineer
  23. 23. PCIC MIDDLE-EAST 201423 Protection: Rodents, Insects & Snakes “I'm involved in a project where the 15 kV service- entrance gear to a facility is mouse and rat-infested. They've chewed the insulation on conductors, and generally left trails all over everything….I'd really like to see the building sealed tight.” John M http://forums.mikeholt.com/showthread.php? t=144240
  24. 24. PCIC MIDDLE-EAST 201424 Protection: Rodents, Insects & Snakes “Yes. I experienced rodent entry into HV and MV switch gear in different companies I worked with. Twice lizard entered into MV switch gear, caused flash over which led to total power failure. Once a snake entered into 11KV switchgear and resulted in trip of the bus section…”
  25. 25. PCIC MIDDLE-EAST 201425 Protection: Rodents, Insects & Snakes …In both cases the identified reasons were similar. Openings in switch gear providing access to cable compartment, growth of grass and weeds around the substation and non installation of rodent repeller in the substation. The total power failure was due to failure of protection system and problems with protection coordination.” Senior Electrical Engineer
  26. 26. PCIC MIDDLE-EAST 201426 Work Process & Design Approach Critical Decision: Field decision or engineering decision? OR
  27. 27. PCIC MIDDLE-EAST 201427 Work Process & Design Approach Critical Decision: Field decision or engineering decision?
  28. 28. PCIC MIDDLE-EAST 201428 Work Process & Design Approach Critical Decision: Field decision or engineering decision?
  29. 29. PCIC MIDDLE-EAST 201429 Work Process & Design Approach Critical Decision: Field decision or engineering decision?
  30. 30. PCIC MIDDLE-EAST 201430 Project Award FEED Decision for cable entry methods, EMC requirements & project standards Detailed Engineering Constructio nEPC Installation Completion Preliminary MCT drawings to develop apertures / cut-out sizing. Approved Vendor List Engineering specification – Frame configuration and acceptance Bill of Material finalized from final cable schedules Materials list to relevant sub-suppliers Confirm frame specs Detail design of modules Logistical services On-site installation training to contractors & maintenance teams On site validation inspections Project documentatio n Work Process & Design Approach
  31. 31. PCIC MIDDLE-EAST 201431 EPC / Design – Required Information Input MCT Design Software Issue Cable Transit Schedule NO: return to MCT manufacturer with Comments Cable Schedule Equipment Layouts Building Layouts Cable Routing Cable Specification Installation Specifcation Cable type & description Cable #, routing to/From Location of Transit Installation Requirements Info Share to Vendor Cable data to MCT Vendor for Design Client Input Data to Transit Designer Transit Detail Drawings Bill of Material Certifications & Installation Instructions Issue specification Check and Approved Yes No MCT Manufacturer – Required Actions and Output OR Work Process – MCT Design
  32. 32. PCIC MIDDLE-EAST 201432 Specification Checkpoints for Multi Cable Transits Variables •Blast load demands •Fire demands •Environmental (weather) or IP demands •Operating Temperature •Cable retention or pull force demands •Corrosion demands / material requirements •Preferred installation method •Bonding, earthing, EMC demands Interfaces •Application - wall / floor / enclosure •Structure Material •Cable
  33. 33. PCIC MIDDLE-EAST 201433 Simple QA / QC checkpoints for MCT installations: • Fully-tightened compression unit – most common failure point! • Flashlight / daylight test – if you can see light through the transit, it should be re-installed or compression tightened • Pull test – a simple pull on the cables will confirm proper installation − Slippage indicates oversized insert block for cable O.D., or − Lack of proper compression Installation Checkpoints for Multi Cable Transits
  34. 34. PCIC MIDDLE-EAST 201434 Conclusions • Project owners / end users should develop, then communicate standards for cable entries − This will increase project safety, improve project efficiencies, and reduce design and installation risks – − we should learn from offshore & marine markets • MCT devices are simple, fit-for-purpose solutions that can add protection to your projects, people, equipment and operations against the hazards of blast, fire, weather (IP), rodents and vapors • MCT devices are available for retro-fit to exsisting openings without removal / re-glanding of cables • Manufacturers are readily available to provide MCT design support as well as onsite trainings and inspections and should be consulted early in projects to optimize efficiency and safety

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