The purpose of this method statement is to provide general guidelines for cable laying and cable termination for control and signal cables.
Scope of this method statement covers the followings activities.
- material handling
- procedure
- precaution
- testing
- inspection
The following documents are considered as reference documents:
- project standard installation drawings
- project specifications
- project quality plan (pqp)
- inspection and test plan
Mandatory Tools
- Hand Drill Machine
- Hole Saw
- File
- Drum Jacks
- Axle
- Cables Rollers
- Certified Test Equipment.
- Cable Knife
- Cable Cutter
- Lugs Press
- Side Cutter
- Wire Stripper
- Insulation Tape
- Hack Saw
Abbreviations
SE: Site engineer
SUP: Supervisor
ITP: Inspection and test plan
E&I: Electrical and instrument
QA/QC: Quality assurance and control
MS: Method statement
IFC: Issue for construction
PPE: Personal protection equipment
HSE: Health safety & environment
PTW: Permit to work
Responsibilities
Supervisor will check cable routing as per project drawings and specifications, all cables, control and instrument to be laid and installed as per above standard details.
Site engineer is to ensure that all activities mentioned above comply with project drawings, specifications and standard details
PTW Holder: Work permit system will be followed. work-permit coordinator will be responsible for this and the work-permit holder will be responsible to follow work-permit requirements.
Method of Cable Laying Work
Receipt and storage of material
The material received from client shall be stored in designated area of store.
arrangements shall be made to protect against effects of weather and environment.
Arrangement cable laying for termination
- preparation of gland hole in bottom plate of gland box.
- marking of gland hole as per size.
- using of hole saw with drill machine.
- filing of sharp edges of gland hole.
Pre-installation requirements
- the site engineer is to check conformity with cable schedule, suitability of cable route and prepare a cable laying plan.
- insulation resistance of the cables shall be checked before laying cables.
Preparing for Cable Laying
- cables rollers are to be used for laying cables over cable trays to reduce friction and prevent damage to the cables sheath.
- cables rollers are to be arranged at bends and change of elevation according to the minimum bending radius of the cables.
Cable Laying Procedure
Cable drum is to be shifted to site and jacked up for laying out. the drum jacking arrangement is to be suitable for the size and weight of the drum.
Unrolling of the cable is as per direction shown on drum.
For large size cable, a proper size cable pulling sock shall be used.
sufficient no. of skilled & unskilled workers are to be employed to lay the cable taking care of the following:-
- the cable does not stray away from the route and remains on the rollers.
- the cable does not touch or scratch against any object damaging it in any way.
- the cable is pulled uniformly all along the route.
Cable Termination Procedure
All jointing and termination work shall be carried out by trained technicians, experienced in such work for the operating voltage concerned.
Proper crimping tools shall be used for compression type lugs.
All cables are to be terminated used glands of proper type and size as per area classification.
The gland shall be assembled strictly in accordance with the manufacturer’s instruction, particular attention being paid to ensuring good mechanical and electrical contact between parts with out excessive strain or distortion of cable.
The entire body of the cable must enter the gland. the cable shall be on a straight axis from a point at least six diameter before entering the gland. seals shall be checked for correct size at the point of application.
Unused cable entries shall be closed with plug suitable for the degree of protection and classification.
Circuit Identification
Proper identification tags shall be used for identification of the cables. Cables cores shall be positively identified at every terminal point, in accordance with the drawings and specification.
Inspection
Inspection and test plan specific to project requirements shall be followed and inspections activities are recorded on the formats. .
Precautions
existing installations
- no work in the immediate vicinity of existing electrical installations shall be allowed without valid permit to work.
- where it would be required to work in the vicinity of electrical equipment all necessary precaution to avoid accident contact with live conductors etc. would be taken.
- a competent qualified electrician shall carry out installation modification or work in the immediate vicinity of any electrical equipment under full time supervision.
new installations
- All the pre-assembled racks (par’s), pre-assembled units (pau’s) and vendor-assembled units (vau’s) shall be pre-installed with the secondary lighting system, only the interconnection to be carried out at site.
- All the modular buildings (vsd and subsation-11) shall be pre-installed with the internal wiring, only the interconnection to be carried out at site.
- Cables in cable trays shall be protected from welding sparks and other falling objects by using gi sheet etc.
- Cables insulation scraps shall be removed on daily basis from panels / control rooms.
Scaffolding
- Scaffolding shall not be disturbed or altered by any unauthorized persons. where alterations are required an authorized scaffolder would be used to carryout the work under competent supervision per safety tag system.
- Where materials are to be positioned on scaffolding it shall be ensured that the scaffolding is not overloaded.
- Scaffolding shall be inspected regularly for suitability.
- If there is any doubt about the security of any anchorage, suspension points of ties for a scaffold e.g., strength of existing building/ structure, or these under construction, the client’s representative shall be consulted before proceeding with erection.
Safety Instructions
During the installation all measures shall be adopted to ensure safe working.
- Client site management system shall be implemented
- All personnel involved shall use necessary ppe.
- all equipment will be inspected by hse (tmegc / gilf classic) prior to use.
- Access and good housekeeping will be maintained.
- Fire extinguisher will be available at all work fronts where applicable.
- All activities at heights will be provided with suitable working platform
- When working at height proper fall protection measures shall be taken.
- All access ladders and scaffolding shall be secured and safety tagged before use.
- Waste management should be strictly followed to keep the job site neat and clean.
- The following personal protection wears shall be used safety helmet, safety goggles, safety shoes, hand gloves, and gas mask.