Explain in detail the steps that must be taken to ensure that the task is carried out safely (include drawing and sketches where required, include pre commencement of work activities and the work itself in a chronological manner).
A. Verify IFC drawings availability
B. Verify Documents for QC material receiving inspection
C. Mobilization of equipment
D. Transport of materials loading & Unloading
E.L V Cable Pulling
PURPOSE
This Method Statement covers the work method and procedure for Low Voltage Cable Laying / Pulling to be
carried out in Waad Al Shamal Integrated Solar Combined Cycle Power Plant Project. This method was prepared as
guideline for effective enforcement of work thus; construction personnel have to determine the applicability and
feasibility of this MS in accordance to approved construction drawing, cable specifications and site condition.
REFERENCE DOCUMENTS
• Contract Agreement
• Project Technical Specifications
• Applicable/ Approved International Standards
• Issued For Construction Drawings
• Manufacturer’s Instructions
DEFINITIONS AND ABBREVIATIONS
• IEC International Electro-Technical Commission
• NEMA National Electrical Manufacturers Association
• RSI Request for Site Inspection
• MRR Material Receiving Report
• NCR Non-Conformity Report
REFERENCE STANDARDS
NFPA 70/NEC National Fire Protection Association/ National Electric Code
ASTM American Society for Testing and Materials (B3 Specification for Soft or Annealed Copper Wire)
IEEE Institute of Electrical and Electronic Engineers
383 type test of class lE electric cables
1202 Flame testing of cables for use in cable trays.
RESPONSIBILITY
Site Manager — Determine all requirements needed in order to comply with contractual requirements and safety standards.
Construction Manager – Lead all construction activities and enforce strict adherence to all project requirements.
Electrical Superintendent — Ensure that work once started is carried out as planned and that the applicable standards are
complied with. Check working methods and precautions to be taken by the supervisors/foreman before commencing work.
Field Engineer – Ensure that all related works are carried out in accordance with approved Issued for Construction
drawings, specifications, schedule, quality and safety. Report to Construction Manager.
Supervisor/ Foreman –Supervise all field installations. Reports to Electrical Superintendent
QC Inspector – Shall be responsible for conduction surveillance and inspection duties for work and ensuring quality
compliance and efficient recording and reporting of results if required. He shall review all relevant documents, material
conformance certificates and non-conformance reports. Prepares Request for Site Inspection.
Safety Manager/Officer — Ensure that HSE plan is being implemented and monitored.
METHODS AND GENERAL GUIDELINES FOR LOW VOLTAGE CABLE PULLING/LAYING
General Requirements
• Cables in ducts. Ducts and slots in concrete slabs will be checked to ensure that they are free from obstructions
before cables are drawn in. Where draw-pits are present each one shall be given a unique identifier which shall be
included on all layout drawings. Lubricants or materials used to assist with drawing cables into the ducts or to seal
the ducts after the cables have been drawn in shall have no detrimental effect on the cable sheath.
• Cable routing and segregation. All cables will be installed to have adequate clearance from other services. Cables
shall generally be routed to avoid hot and fire-risk areas, and to minimize the risk of damage from any external
heat source. The layout of all cables shall be arranged to have adequate clearance from other services.
• Cable separation must be considered with the corresponding voltage level. Power cables are not to be installed on
the same tray or ladder rack as control cables.
• Control cables as well as the cables of the Communication Systems will be laid sufficiently apart from the power
cables so that no interference will occur and the transmission of fault signals is excluded.
• Where control cables are required to be run along the same route as one or more power cables, the control cable
tray can be routed underneath the power cable tray.
• To enable complete redundancy to be maintained, two separate routes may be used for the data highway and all
other redundant circuits. Redundant cables will take two distinct paths, when not routed in duct banks.
• The power and control cable systems of each individual generator unit or station auxiliary system will be routed
along a different path from other unit or station auxiliary systems.
• Routes plans shall be checked for all underground cables. The plans shall accurately show the location of the
cables, including road crossings and underground services in the vicinity of the cables.
• Cable risers near gangways or in electrical rooms that are exposed to possible mechanical damage are to be
protected.
• In areas where there is a possible risk of oil or other combustible material falling onto cable trays and ladder racks
the trays and ladder racks may be mounted in the vertical plane.
Cable Handling and Preparation
Field engineer and supervisor shall check approved issued Construction drawing, cable route plan and cable list.
Field engineer and supervisor shall check at site the completion of the following cable route as shown in the
construction drawing:
• Cable trench
• Duct bank and conduit
• Cable tray installation
• Sections and details
Ensure that a worksite location has been released and ready for safe work execution. Cable installation will be
carried out by technically qualified and competent personnel. Cable continuity and insulation test of cable will be
checked before cable pulling activity. After cable test, insulation test equipment (meg-ohm meter) must be
discharged and cable cores must be grounded to discharge any induced voltage.
Check for separation of cables as per voltage classification and approved Construction drawing.
Clean cable duct before cable pulling by blowing using air compressor, appropriate mandrel and wire brush.
Cable pulling supervisor and foreman shall organize the cable pulling plan which includes the following:
• Cable schedule/pull sheets review
• Cable drum schedule
• Measurement of cable to be pulled
• Location of cable reel/drum
• Lifting of cable reel and placing at cable stand
• Placing of cable rollers
• Pulling machine preparation, for large cable
• Number of person and each positions
• Communication device to be used are established
• Cable basket, winch and rope to be used (cable pulling at trench and conduit)
• Preparation of scaffold for cable pulling at height
• Preparation of miscellaneous materials
• Cable tag/wire identification installation
• Barricades and warning signs are in place.
• Both sides of each duct bank shall be protected to avoid falling material such as stones, etc. on cables
Handling of cables. The following will be considered during handling and unloading of cable.
• Cable reel should be handled in accordance with manufacturer’s instruction and cable handling procedure
• Cable reels should be handled on edges of flanges only (not on flat side of flanges)
• Reels shall be chocked during transporting to prevent damage from load shifting
• Cable reel must not be placed where they would impede personnel
• Cable reel shall not be dropped. Ensure that lifting equipment and material are inspected and in good condition.
• A void cable reel over sharp edges.
• Cable reel should be located on hard surfaces and avoid sinking into soil during handling.
• Cable reels should be rolled in accordance with roll directional arrows labeled on reel flanges
• When fork lift handling, reel flanges will be cradled between the fork tines, and should touch flange edges at all four points
• Cable drum must be transported from stockyard to site location. Roadway for unloading location must also be check due to any on-going construction activity on road
FIGURE A. TRANSPORTATION
Cable Pulling
Refer to cable schedule and verify in actual site condition the measurement required for cable pulling from starting point to end point. Cable pulling report shall be filled up and submitted to document controller for master file.
Cable reel/drum location will be identified through site inspection and will be shown in cable pulling route drawing.
Cable reel/drum stand:
• Cable drum shaft and trolley
• Cable stand will be used for uncoiling of cable during pulling
• Cable stand shall be checked as per capacity and requirement of cable reel/drum
• Cable stand shall be check for good condition, and shaft shall meet the capacity requirement of cable reel/drum
• Movable parts will be checked for free willing and grease will be applied as needed
• Use steel plate base for cable stand to avoid sinking at the ground.
Transport cable to designated area. Insert shaft in the flange, lift the cable drum and place in the cable stand.
Check the correct roll direction of cable.
When rollers are to be used, ensure that cable rollers are installed and secured with appropriate space. Use cable roller intended for long bend and offset route of the cable (heavy duty corner roller). Cables must not be in contact with surfaces which can damage external sheath. Communication device should be ready before and during cable pulling activity
Cable pulling at duct bank/road crossing:
• Where cable was to be pulled in a conduit, ensure that the conduit was clean and free from debris.
• Apply approved lubricant during pulling of the cable.
• Cable shall be protected against abrasive surfaces and edges during pulling at conduit with appropriate side
roller
During Manual Cable Pulling and Handling:
• All workers shall wear complete PPE and shall follow the agreed instruction and safety procedure in cable pulling
initiated by their supervisor.
• Supervisor/foreman shall have adequate person to pull the cable
• Persons will be assigned at the cable drum location for its rotation and feeding of cable, at cable bend, at pull
boxes, at cable ends and at any intervals needed as per work condition.
• If wire rope and basket will be used for cable, check and secure for tightness. Swivel will be fitted to avoid twisting
of cable and damage to the external sheath.
• Provide protection to cable for any edges and abrasive surfaces
• Establish a good coordination and clear instruction while pulling the cable to avoid incidents in loosing of grips,
cable drop or caught between
• Cable route shall be checked when cable was hard to pull, it should be easily pulled avoiding excessive tension
• Cable can be flaked, to avoid any jam or twisting when cable needs to be pulled to succeeding route.
During Cable Pulling by Winch:
• Wherein pulling machine/puller winch will be used during activity, it must be inspected and checked for good
condition.
• Always refer to manufacturer’s instruction and safety manual of pulling machine. Machine shall be operated by
competent person.
• Safety Check and Precaution
• Review and follow approved Safety Job Hazard Analysis
• Review and recheck material requiring certification
• Working area must be cordoned-off and use warning sign to limit access only for operator and allowed personnel.
• Supervisor and foreman shall designate person’s position at cable route. Personnel for cable pulling shall
thoroughly check cables during pull, cable rollers and cable reel. There shall always be assigned person in each
corner route, cable reel, in the pulling machine and at end side.
• Prepare cable basket and winch cable. Cable basket size will be according to diameter of the cable.
• Ensure that basket and winch cable/rope for pulling is secured and tight. Ensure that cable basket and winch
cables were free from damage.
• Check for any loose object and connection in the potential path whipping back of a rope/winch cable after failure
under tension.
• Swivel connector will also be connected to prevent winch cable from twisting.
• A void excessive bending of the cable.
• Cable shall be pulled in a constant speed; avoid excessive tension during straight and in corner pull.
• When excessive tension was observed, pulling should be stopped and check cable path for any obstruction. Also
check that cable rollers were freely rotating, cables entering duct were properly lubricated, edges and offsets were
checked and cables were in proper slope
• Care shall always be taken to avoid damage on the cable insulation while pulling.
DURING CABLE PULLING ON CABLE TRAY/LADDER
• Check completeness of cable tray and visually inspect to ensure that is free from debris, burrs and sharp edges
that can damage the cable. Put insulator/rubber to protect cable from edges of the cable tray. Verify allowable
space for laying of cable on tray/ladder.
• Cables that is to be installed on tray shall be laid neatly in parallel runs with no crossing over of cables except as
approved by the Client
• Cables shall be fixed to the ladder with cable ties threaded through the slots in the ladder rungs. Cable shall be
tied on ladders run horizontally with rungs horizontal and on vertical ladder or ladder run horizontally with
rungs vertical (on edge).
• Cables installed on cable tray must be fixed with cable tie.
• Smaller cables may be tied in groups. After cable ties have been ‘zipped’ tight, the ends shall be trimmed and the
cut ends removed as part of site cleanup
• When positioning cables on the
tray, proper separation shall be maintained between
control/instrument/communications cables and power cables run on the same ladder.
• Cables must leave the tray through the rungs and not over the side rail.
CABLE PULLING FROM CONDUIT
The following cables should not be run in the same conduit or duct:
• Cables of different voltages
• Cables of more than three wire sizes
• Cables for ac and de circuits
• Cables for power and control/instrumentation/communications
• Conduit runs shall be completely assembled, swabbed through to remove any foreign debris prior to cable pulling.
• Care shall be taken during pulling of cable in conduit to minimize friction between the cable and the conduit
• A recommended lubricant can be used to reduce friction.
• Where a cable enters a conduit or duct, provision shall be made to prevent the ingress of water or other liquids by
glanding or sealing with glued heat shrink.
When the cable reaches the equipment or end of trench, measure length of cable required to be cut. Allowable extra length
of cable must be considered for dressing and termination requirements.
Cutting cables must be done with appropriate tools such as hydraulic shears, hand shears or hacksaw (ensure the required
length before cutting).
After cable pulling, provide protection for the floor and the cable (plywood or tarpaulin plastic). Area shall be barricaded,
secured and obstruction to passageways shall be avoided.
Immediately after completing the cable pulling, cable was laid and cut, protect both ends of cable or splicing secured with
insulation tape or heat shrinkable cap to avoid moisture absorption to the cable strands. The remaining cable on reel shall
also be protected.
If in the substation, cable originating point, is not ready to receive the cable, sufficient length of cable will be left on cable
drum and the drum will be removed from jack and placed on the cable trench, as closed possible to the cable entry.
Similarly at the end point, an area will be identified and the required length of cables will be coiled. The area will be hard
barricaded and tarpaulin may be used to protect the cables.
Temporary identification label shall be made at each end; the identification shall be as per cable list. Final label or
identification will have to be installed after termination is completed.
Underground cable shall be marked with stainless steel tag fixed with stainless steel cable ties at required distance. Install
tag number all along the route in reference to Project Specification and drawing.
Continuity, insulation test of cables will be checked after cable pulling and before final cable termination.
Marked-up/ As-built drawings for any changes made.
Clean the area after completing cable pulling, cable tagging were installed. Housekeeping to be performed daily before end
of shift.
After cable pulling all the trenches shall be barricaded with concrete protection to avoid heavy equipment such as trucks,
cranes, etc. from passing over the laid cables
INSPECTIONS
QC Inspection
All inspections shall be coordinated by CGA QA/QC Inspector, who will implement the inspection program and notify all
parties involved in advance of the scheduled dates of inspection to enable them to participate. Insulation resistance test and
high potential test will be applied according to vendor’s recommended test voltages and testing procedures.
Cable shall be inspected and tested (pre-installation and pre-commissioning requirement) using approved forms.
Internal and preliminary inspection must be done before submitting to Contractor for Final Inspection. Verify and check
that cable installation complies with project specification, cable schedule and approved construction drawing.
RSI will be raised for inspection once work and internal inspection was completed.
Relevant records shall be signed by all the required parties and originals kept by the QA/QC Department.
Acceptance criteria for inspection will be within Project specification and standards. Required actions will be taken place
as per site work condition for remarks and punch lists noted during inspection and testing.
As-Built Drawing
Document controller will be responsible for maintaining a complete set of Construction drawings, Material Take-off
(MTO) and Data sheets dedicated for up-to-date marked-up of any actual field changes to the drawing issued or any
revisions.
Once the scheduled area/portion is completed, foreman will inform the supervisor for any changes in the approved
drawings.
The Supervisor makes “As-built” drawings in Master Copy immediately after completion of works (“As-built” – any changes in the approved drawings, P&ID and specifications marked in red according to actual constructed condition) and submits to field engineer who will review and forward the As-built Drawings to QA/QC department.
After QA/QC department reviewed and verified it, the gathered “As-built” red-marked drawings submitted by Construction will be processed for submittal to client and a Master copy will be kept by CGA document controller.