Your SlideShare is downloading. ×

Standards

590

Published on

Published in: Education
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
590
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
22
Comments
0
Likes
1
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Marine Electrical Standard Requiremnent
  • 2. Lesson overview• Shore based connection requirement for equipment for shipboard equipment• Electrical system and dynamic marine environment- vibration and voltage fluctuation• SOLAS minimum requirements for electrical machinery installation• Electrical equipments installation on board ship - From indicator bulb/lamp up to main propulsion
  • 3. Objectives• To know general requirements for electrical machinery on board ship• To understand general requirements for provision of electrical power and lighting for normal & emergency operation
  • 4. Introduction• Must meet minimum standards specified by various national & international organizations• For British registered vessel, to comply: – Regulations for the Electrical and Electronic Equipment of Ships - Institution of Electrical Engineers (IEE) – British Standards Institute (BSI) - combined with Recommendations for Electrical and Electronic Equipment of Offshore Installations• The Merchant Shipping Rules - MCA• SOLAS – IMO Convention• British Standards (BS)• International Electrotechnical Commission (IEC)
  • 5. Introduction• General requirements - refer to SOLAS requirements• Chapter II-1 - outlines requirements for Ship construction sub-division and stability, machinery and electrical installations• 5 Parts: – Part A General – Part B Sub-division and stability – Part C Machinery installations – Part D Electrical installations – Part E Additional requirements for periodically unattended machinery spaces
  • 6. • Part D: – Regulation 40 • General – Regulation 41 • Main source of electrical power and lighting systems – Regulation 42 • Emergency source of electrical power in passenger ships – Regulation 42-1 • Supplementary emergency lighting for Ro-Ro passenger ships – Regulation 43 • Emergency source of electrical power in cargo ships – Regulation 44 • Starting arrangements for emergency generator sets – Regulation 45 • Precautions against shock, fire and other hazards of electrical origin
  • 7. • Standards specified met when ship is designed, built, approved and classified• Ship owner & operating staff to maintain vessel and its electrical installation to Class requirements throughout ships lifetime• Periodical survey - to check installation is maintained to Class Rules
  • 8. Items subject to survey• Generators and Governors• Circuit Breakers• Switchboards and Fittings• Cables• Insulation Resistance• Motors and Starters• Emergency Power Equipments• Parts of Steering Gear• Navigation Light Indicators• UMS vessels• Tankers
  • 9. • For UMS - survey of associated alarms, controls and fire detection is required• For tankers/gas carriers & others transporting flammable cargo - additional survey for electrical equipment in hazardous areas• Carried out during each docking survey & annual survey - Means - electrical equipment in hazardous area is surveyed every year
  • 10. Generators & Governors
  • 11. Generators & Governors• Clean• Respond correctly to controls & load changes• Stable operation when running in parallel• Windings - free of dust, oil and moisture• Visual check - deterioration, abrasion or cracking of insulation around winding end coils on stator• Insulation test to carry out while machine still hot after running on load• Minimum 1.5 MΩ for new equipment• Surveyor - > 1kΩ/volt min value for 440V genset• HV equipment – min IR level (kV + 1) MΩ• e.g. for 6.6 kV motor, the acceptable min IR would be 7.6 MΩ
  • 12. Generators & Governors• Appropriate action taken before carried out megger test• Contact surface of commutator or slip-rings• Contact surfaces – smooth & concentric without signs of pitting or deep grooves• Carbon brushes - adequate length, correct spring pressure and properly contoured onto its commutator or slip-ring• Important to remove excess carbon dust in brush gear & around rotor coils• To run tests, on load, confirm of proper governor & AVR operation• Correct indication – V, f, A, kW, power factor• Governor response to sudden load changes - within declared specification• Stability of load sharing during parallel operation - clearly demonstrated
  • 13. Circuit breaker
  • 14. Circuit breaker• Visual examination - main, arcing and auxiliary contacts for wear, misalignment and overheating• Similar inspection - fixed and moving isolator contacts at rear of circuit-breaker• Arc chutes - clean, free of arc debris and correctly aligned• Internal wiring - good condition & end connections tight• Mechanical linkages - checked for wear or stress• Tests – close and trip operations while in isolated position – racking mechanism - free moving & fixed main terminals must shuttered off when breaker is withdrawn• Emergency hand charging (if fitted) - correct operation of mechanical indicators (open, closed or isolated)• UV release mechanism & OCR settings for level and time delay - clearly set• Basically, OCR trip generator breaker - set for 130% of FLC with 3s delay• In addition, to suit generator thermal capacity & coordinated with overall protection scheme for power system• Only proper current injection test – prove manufacturers I/t characteristics & settings (specialist task)• CB time delay mechanisms with oil dash pots – to filled to correct level with clean oil of maker recommended type
  • 15. Switchboard & fittings
  • 16. Switchboard & fittings
  • 17. Switchboard & fittings• Section / distribution board – clean• Includes all internal / external panel surfaces, instrument faces and control switches• Thorough cleaning inside main swbd carried out only when the board is completely dead• Bus-bar & aux connections checked for tightness during major internal clean up• Overheating signs at connection - loose joint• Direct heat testing (IR thermal camera) - useful technique for locating hot- spots• Bus-bar supports - examined for surface tracking & damage to insulation material• All internal wiring securely fixed• Cable entries at bottom of switchboard sealed with non-flammable material – prevent dirt & act as fire stop• Earth bar securely bonded to both board frame (ships hull)
  • 18. Switchboard & fittings• One secondary terminal of each CT) and instruments and relays metal cases should wired to main earth bar• Hinged panel doors bonded with earth strap to swbd frame• Feeder isolator & fuse holder contacts - checked for mechanical wear / damage due overheating / arcing at contacts• Lightly smear moving contacts with contact lubricant – recommended• Operational tests - synchronising controls & generator protection relays (reverse power & preferential tripping)• Typical reverse power trip settings – 5~15% of generator power rating, with 0.5~2.5 sec for diesel drive• 2~5% and 5 s - turbo-generator settings• E.g - cargo winches & cranes may feed power back into supply network, under light load, such feedback may cause generator to trip on reverse power if time delay set too short
  • 19. Cable
  • 20. Cable• Close visual examination beside megger test• Inspection - external damage of cables outer sheath and wire or basket weave armouring (if fitted)• Adequately supported along horizontal / vertical runs by suitable clips / ties• If running along open deck with expansion loops - examined for abrasion and wear• For cables pass though bulkheads - correctly glanded or through stopper boxes, prevent fire passage between compartments• Common insulations onboard - EPR (ethylene propylene rubber) or butyl rubber, sheathed with PCP (polychloroprene) or CSP (chlorosulphonated polyethelene)• EPR/butyl subjected to oil vapour - to tape / sleeve cable ends• Flexible cables to light fittings, power tools, etc. - inspected for mechanical damage, repeated dragged and chafed• Copper strap / flexible earthing braid/wire - bond equipment steel frame to ships hull
  • 21. Insulation resistance• Surveyor - results of recent insulation tests on all 440V & 220 V• List indicate test dates, weather conditions (hot, humid, etc) & comments (e.g. machine hot or cold)• For generators & main motors - IR trend, history of past results
  • 22. Insulation resistanceRequired to test on selected motors• Visual examination - frame & terminal for damaged or missing parts• General neglect suspected if motor covered with dirt, oil or rust• TEFV induction motors - require less attention as windings well protected• Drip proof, weatherproof & deck water tight – thoroughly inspected• May need to open - check ingress of oil / water, insulation damage & internal corrosion• Commutator / slip-ring - checked for rotary contacts and brush gear• Cargo cranes and winches are not strictly part of a survey as they are not considered essential to the safety of the ship.
  • 23. Insulation resistance• Running test – vibration, noise, worn out bearings & ampere compared to rating plate• Remote stop/start buttons, regulating resistors etc. - check for burned & misaligned contacts• General condition of starter equipment - loose connections, worn pigtails on moving contacts, badly carbonised arc chutes & overheating on coils, transformers & resistors• Dust / weather proof features - in place & serviceable• Functional checks – starts from local, remote and emergency, signal lamp status• OCR trip settings compared with motor FLC rating• Fuse size & type for starter - checked against makers drawings & motor rating
  • 24. Electrical power & associated equipment• Sequence & operation of emergency generator - manually & automatically• Emergency switchboard - voltage, current and frequency checked when powered by emergency generator• Functioning of emergency lighting, fire pump & other emergency equipment• Interlocking arrangements between main & emergency switchboard• Auto-start relays (voltage / frequency operated) examined and tested• Emergency battery installation & charging rectifier• Battery – dry, well ventilated, top parts clean, terminal & connections free from corrosion & greased, proper electrolyte level & correct SG value• Safety notices & PPE available adjacent to batteries & proper ventilation• Battery charging equipment - checks for dirt, overheating, loose connections & correct functioning of indicators, instruments and alarms
  • 25. Steering gear parts
  • 26. Steering gear parts• 3 important parts: – Power unit – Steering control – Indications and alarms• Power unit - duplicate motors & starters supplied from main swbd• SOLAS requirements - one motors to be supplied from emergency swbd• Motors, starters & c/o supply switch units to be inspected• Rudder control (hydraulic telemotor or electric controller), supplies, changeover facilities for steering wheel and auto pilot must tested & well functional• Rudder swung from 32° port to 32° stbd in 28 sec with loaded condition• SG status indications operate correctly - steering flat, MCR & on bridge• Bridge indication should compared with direct mechanical indicator on rudder stock in steering flat• Motor over current alarms – test by simulating over current relay• SG motor does not have OCR protection – fuses only• Hydraulic low level alarms - correct initiation by level sensors
  • 27. Navigation light indicators
  • 28. Navigation light indicators• Indicator operates correctly & shall gives appropriate alarms• Simulation – by pulling the fuse• Power supply must duplicated & c/o facilities checked• Visual inspection on cable to the lights• Actual light fittings for navigation - part of Safety Equipment Survey
  • 29. UMS operation• Apart from basic survey, additional survey required to include alarms, fire detection, controls and fail-safe features• Alarms associated with ME, AE, lubrication & cooling - tested for correct operation• Testing of circuits for sensors – manually by switch or simulate to alarm condition - prove function correctly• Sensor calibration & alarm annunciators – specialist• Initiation and action of automatic shut down features to be tested• Essential drives for lubrication, cooling & fuel are duplicated - on duty/standby basis, automatically start up standby unit if duty pump pressure loss• Automatic start-up (under voltage & under-frequency relay) of emergency generator demonstrated, run up to speed & supply voltage to emergency swbd
  • 30. UMS operation• Stby generator starts automatically if loss of duty generator & supplying voltage within 45 sec• Followed by automatic restarting of essential auxiliaries - lubrication, cooling, fuel & steering• Bilge level alarms with automatic bilge pumping must proven• Main & stby power supplies to overall alarm monitoring system - inspected & tested• Stby power arrangement - backup battery & its trickle-charger to inspect• Tests made on UMS alarm system to verify: – alarms displayed on main console relayed to group alarm panel on bridge – duty engr call system - duty engineer cabin, duty mess and lounges – Allowance of 2-3 minutes to respond to machinery alarm, otherwise dead man alarm sounded• Complete inspection / test of fire detection system• All smoke, heat & flame sensors - function correctly, giving audible & visual alarms• Hand operated fire alarm switches (break glass) - examined & to be tested• ME controls functional & tested from bridge, local & emergency position• Operational features of ME control & indication - demonstrated during full engine test• All equipment & connections associated with engine control - examined for wear & tear, insulation level, cleanliness, loose connections and overheating
  • 31. Tanker• Electrical equipment - surveyed every 4 yrs & during docking• Hazardous area electrical equipment - surveyed every year• Common hazardous area electrical equipment - flameproof enclosure type (Exd) - light fittings, motors, starters, push-buttons and alarm bells• Inspected for surface cleanliness, corrosion & secure mountings• Light fittings – cement, bonds the lamp glass to its frame - inspected for cracks or indentations• All bolts in place, evenly torqued-up and of correct type• Edges of ‘Exd’ flamepath flanged joints - not painted over / impeded• Must be adjudged weatherproof with correct (approved) gaskets or O rings in place• Fittings may opened up - check condition of flamepath surfaces for corrosion, pitting or scratches• Ex Certification & equipment rating label must not painted over• No alterations allow on Exd equipment without permission from Certification Authority - lamp size & its rating
  • 32. Exd Flamepaths
  • 33. • Pump rooms - pressurized light fittings (Exp)• To confirm - fittings are purged & pressurized before light is switched on• Lights automatically switched off if air pressure drops• Instrumentation & communication equipment - must intrinsically safe (Exi)• Most Exi - zener barriers connected in line with IS circuits & fitted in safe area, outside hazardous area• Test zener barriers – uneasy task, accepted if equipment function correctly when circuit fault arise• Visual inspection during installation• Barriers have secure connections & bolted to earth strap, bonded to ships hull
  • 34. Exi Barrier Circuit

×