Repair or modify traction and rolling stock electrical circuits
Overview
This standard identifies the competences you need to repair or modify traction and rolling stock electrical circuits, in accordance with approved procedures. You will be required to repair, modify and update circuits in accordance with specifications and latest issue drawings and standards. You will be expected to remove and replace cables, add new cables, change breakout points and change the routing of cables. You will also be expected to change components, connectors, units and mounting trays. You will need to show proficiency in using various tools and equipment for cutting, stripping, crimping and soldering, and in the installation of the various wires, cables and components that make up the traction and rolling stock electrical systems and circuits worked on. The term traction and rolling stock used in this standard applies to passenger, freight and on-track machines (OTM). Where it is relevant these standards also apply to traction and rolling stock that has been fitted with the European Train Control System (ETCS).
Your responsibilities will require you to comply with organisational policy and procedures for the repair or modification activities undertaken, and to report any problems with the activities, components or equipment that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You must ensure that all tools, equipment, and materials used in the repairing or modifying activities are removed from the work area on completion of the activities, and that all necessary documentation is completed accurately and legibly. You will be expected to work with minimal supervision, taking full responsibility for your own actions, and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will provide a good understanding of your work, and will provide an informed approach to applying repair or modification procedures. You will understand the repair or modification to be carried out, and its application, and will know about the methods, tools and equipment to be used, in adequate depth to provide a sound basis for carrying out the activities, correcting faults and ensuring that the repair or modification is carried out to the required specification and remains compliant with all standards and regulations.
You will understand the safety precautions required when carrying out the repair or modification activities. You will be required to demonstrate safe working practices throughout, and will understand the responsibility you owe to yourself and others in the workplace.
Performance criteria
You must be able to:
P1 maintain safe working practices and comply with all relevant health and safety regulations, directives, and guidelines
P2 obtain and follow the relevant repair or modification specifications and job instructions
P3 confirm and agree what repairs or modifications are to be carried out to meet the specification
P4 prepare the electrical circuit for the required repair or modification
P5 carry out the system repair or modification using approved materials, methods and procedures
P6 complete the repair or modification within the agreed timescale
P7 ensure that the repaired or modified electrical circuit meets the specified operating conditions
P8 produce accurate and complete records of all work carried out address problems within your control and report unresolved issues.
Knowledge and Understanding
You need to know and understand:
K1 the relevant health and safety regulations, directives, guidelines, and safe working practices and procedures defined by your organisation, as appropriate to the activity and your working area
K2 the isolation and lock-off procedure or permit-to-work procedure that applies to the system circuits (such as electrical isolation, locking off switchgear, placing of maintenance warning notices, proving the isolation has been achieved and secured)
K3 the hazards associated with carrying out repair or modification of electrical circuits, and how to minimise these and reduce any risks
K4 the classification of different voltage levels and the authority requirements for working on them
K5 what constitutes a hazardous voltage/current and how to recognise victims of electric shock
K6 how to reduce the risks of an electric shock (such as insulated tools, rubber matting and isolating transformers)
K7 the personal protective equipment and clothing (PPE) to be worn during the repair or modification activities
K8 how to obtain and interpret drawings, circuit and physical layouts, charts, specifications, manufacturers' manuals, graphical electrical symbols, wiring regulations, and other documentation used during the repair or modification activities
K9 the principles of how the circuit functions, the operating sequence, the working purpose of individual units/components, and how they interact
K10 the procedures and precautions to be adopted to eliminate electrostatic discharge (ESD) hazards when working with and handling electronic devices
K11 the different types of cabling (such as multicore cables, single core cables, steel wire armoured (SWA) cables, data cables, screened cables) their fittings and their application
K12 the different types of electrical component (such as plugs, sockets, switches, lighting and fittings, junction boxes, relays, protection devices)
K13 preparations to be undertaken prior to the repair or modification of the circuit
K14 how to extract and insert new cables in wiring enclosures (such as conduit,trunking and traywork) without causing damage to other cables or components
K15 the methods and techniques to be used for soldering and de-soldering, and the importance of adhering to these procedures
K16 the methods and techniques to be used for crimping and heat shrinking, and the importance of adhering to these procedures
K17 the various mechanical fasteners that can be used, and their methods of installation or removal
K18 the procedure for obtaining replacement parts, materials and other consumables necessary for the repair or modification activities
K19 the importance of ensuring that the completed circuit is free from foreign objects, and that all terminations are electrically and mechanically sound and secure ',checking that faults have not been introduced into other systems and, if the tests have identified a fault that requires rectification, the importance of repeating the testing to confirm that the repair has been effective
K20 how to conduct any necessary checks to ensure that the completed repair or modification complies with all appropriate standards
K21 the methods and equipment used to transport, handle and lift components/cabling into position, and how to check that the lifting equipment is within its current certification dates
K22 the importance of recording the serial numbers of removed and newly fitted components affecting the rolling stock asset tree
K23 how to check that tools and equipment are free from damage or defect, are in a safe and usable condition, and are configured for their intended purpose
K24 the problems that can occur with the repair or modification operations, and how these can be overcome
K25 the recording documentation to be completed for the activities undertaken
K26 the extent of your own authority and to whom you should report if you have problems that you cannot resolve
Scope/range
Scope Performance
During circuit modification and rewiring activities, individuals will:
- obtain and use the correct issue of company and/or manufacturers' drawings and planning documentation as well as the correct version of any maintenance software tools required
- adhere to procedures or systems in place for risk assessment, control of substances, personal protective equipment and other relevant safety regulations and procedures to realise a safe system of work
- ensure the safe isolation of equipment (such as electricity, mechanical, air or fluids)
- provide and maintain safe access and working arrangements for the repair or modification area
- repair or modify electrical circuits using approved techniques and procedures
- apply safe working practices and procedures at all times dispose of waste items to comply with environmental protection guidelines and ensure the work area remains safe
Types of electrical circuits, subject to repairs or modifications, could include:
- single-phase power circuits
- control systems and components
- three-phase power circuits
- direct current power circuits
- wiring enclosures (such as conduit, trunking or tray work)
- traction motor control
- luminaires
- switchgear and distribution panels
- other specific electrical circuits
Repair or modification activities could include:
- replacing cables
- replacing connectors
- replacing sockets
- making changes to looms or circuits
- changing or adding components to panels or sub-assemblies
- changing the position or angle of breakout points
- changing position of electrical units
- adding or removing components from circuits
- fitting new electrical circuits
- changing the route of cables
- removal of cables
- adding further looms or circuits
- addition of cables
- repairing cables
- other specific activity
Repair or modification processes could include:
- terminating cables
- heat shrinking (devices and boots)
- bending and forming conduit
- crimping (tags and pins)
- bending and forming trunking and wiring trays
- fitting mounting trays
- stripping cable insulation/protection
- replacing cable insulation/protection
- sealing and protecting cable connections
- removing cable end fittings
- fitting cable end fittings
- making mechanical/screwed/clamped connections
- extracting/inserting components
- soldering and de-soldering
- allocating identification markings
- other specific process
Repaired or modified electrical circuits may need to be produced in accordance with the following:
- organisational guidelines and codes of practice
- equipment manufacturers' documents
- engineering change documents
- BS, ISO and/or BSEN standards
- company standard operating procedures (SOP's)
- documents such as technical procedures, vehicle maintenance instructions, vehicle overhaul instructions, workshop overhaul standards specifications
Types of paperwork/records that need to be completed and passed to the appropriate people could include:
- job cards
- permits to work/formal risk assessment and/or sign-on/off procedures
- maintenance log or report
- company-specific documentation
- electronic records