Test traction and rolling stock communication-electronic systems
Overview
This standard identifies the competencies you need to carry out tests on traction and rolling stock communication-electronic systems, in accordance with approved procedures. You will be required to carry out tests on a range of communication-electronic systems, sub-systems or assemblies to line replacement unit (LRU) level, to establish and ensure that they are functioning at optimal level and to specification. You will be required to carry out a range of measurements and tests, which may include voltage and current levels, resistance values, waveform, clock/timer switching, pulse width/rise time, open/short circuit, logic state, frequency modulation/demodulation and signal noise/interference levels, as applicable to the equipment you are working 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 carrying out the testing activities and to report any problems with these activities that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You will be expected to work with minimal supervision, taking personal 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 the procedures used for carrying out the required tests and will provide an informed approach to applying the necessary testing procedures. You will understand the equipment being worked on, the test equipment being used, and the various test procedures and their application, in adequate depth to provide a sound basis for carrying out the activities correcting faults, and ensuring that the equipment operates safely and correctly to the required specification and remains compliant with all standards and regulations. In addition, you will be expected to review the outcome of the tests, compare the results with appropriate specifications, determine the action required, and record/report the results in the appropriate format.
You will understand the safety precautions required when carrying out the testing activities, especially those for isolating the equipment and for taking the necessary safeguards to protect yourself against direct and indirect electric shock. 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 follow the appropriate procedures for use of tools and equipment to carry out the required tests
P3 set up and carry out the tests using the correct procedures and within agreed timescales
P4 record the results of the tests in the appropriate format
P5 review the results and carry out further tests if necessary
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 your responsibilities under regulations relevant to the communication- electronic testing activities being undertaken
K3 the isolation and lock-off procedure, or permit-to-work procedure that applies to the testing activities (electrical isolation, locking off switch gear, placing maintenance warning notices, proving that isolation has been achieved and secured)
K4 isolation procedures that are unique to communication-electronic systems
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 classification of different voltage levels and the authority requirements for working on them
K8 the specific safety precautions to be taken when carrying out testing of communication- electronic equipment
K9 the hazards associated with testing communication-electronic systems (such as high voltages/currents, stored capacitive/inductive energy, radio frequencies, misuse of tools), and how to minimise them and reduce any risks
K10 the importance of wearing protective clothing and other appropriate safety equipment (PPE) during the testing activities
K11 the importance of keeping the work area clean and tidy, and free from waste and surplus materials
K12 how the testing activities may affect the work of others, and the procedure for informing them of the work to be carried out
K13 the procedures and precautions to be adopted to eliminate electrostatic discharge (ESD)
K14 how to obtain and interpret drawings, circuit diagrams, specifications, manufacturers' manuals, test procedures and other documents needed to carry out the test
K15 the principles of how communication-electronic or associated systems function and interact
K16 how subsystems and assemblies function within a system
K17 how to determine suitable test points within a system, subsystem or assembly
K18 how to set up and apply the appropriate test equipment
K19 how to determine the calibration state of the equipment, and the actions to be taken if equipment is out of calibration,
K20 how to ensure that the test equipment is free from damage or defect
K21 how to check that tools and equipment are free from damage or defect, are in a safe and useable condition and are configured for their intended purpose
K22 the various testing methods and procedures, and how to apply them to different operating conditions
K23 how to analyse test results, and how to use comparison and sequential techniques
K24 the environmental control and company operating procedure relating to functional testing
K25 the documentation required, and the procedures to be followed at the conclusion of the test
K26 the extent of your authority and to whom you should report to if you have problems that you cannot resolve
Scope/range
Scope Performance
During the testing activities, individuals will:
- plan the testing activities to cause minimal disruption to normal working
- obtain and use the correct issue of company and/or manufacturers' drawings and maintenance 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
- provide and maintain safe access and working arrangements for the maintenance area
- warn others in the maintenance area if they are at risk of injury from the system being tested
- carry out the testing activities using appropriate techniques and procedures
- take electrostatic precautions when handling components and circuit boards
- re-connect and return the equipment to service on completion of the testing activities
- dispose of waste items to comply with environmental protection guidelines and ensure the work area remains safe
Types of communication electronic systems, sub- systems or assemblies on which tests are completed to LRU level include:
- transmitters
- transceivers
- receivers
- aerial systems
- radar systems
- staff communication systems (such as GSMR, PA, cab to cab)
- train control systems (such as AWS, ATP, TPWS, ETCS)
- data transmission lines (such as fibre optics, coaxial, baluns, twin wire)
- display systems (such as crew and passenger information)
- driver-machine interface
- optical systems (such as CCTV)
- built-in test equipment
- data network systems (such as LANs, WANs)
- data network interfaces (such as switches, router, bridging networks)
- any other identifiable electronic system, sub-system or assemblies to Line Replaceable Unit (LRU) level
- environmental control systems (such as temperature, alarms, fire protection, fire suppression)
- electromechanical systems (such as servos, motors, relays, complex switches)
- power generation systems (such as AC/DC generators, batteries)
- power distribution systems (such as single phase/3-phase distribution panels, shore connections)
- traction supply control systems (such as inverters, rectifiers, regenerative braking)
- monitoring systems (such as On Train Data Recorder (OTDR))
- hybrid systems (such as ADC, DAC)
Types of tools and test equipment used could include the following:
- oscilloscope
- temperature testing devices
- power meters
- logic analyser
- Q meter
- spectrum analyser
- current tracer
- time domain reflectometer
- signal generator
- frequency counter
- multimeter
- protocol analyser
- computer-aided diagnostic equipment
- breakout box
- special-purpose testing equipment
- automatic test equipment
- built in test equipment (BITE)
- other specific test equipment
Tests or measurements, as applicable to the equipment being tested, may include:
- correct function
- correct self diagnostic readout
- resistance
- DC voltage/current levels
- heat dissipation
- AC voltage/current levels
- frequency modulation/demodulation
- clock/timer switching
- performance of system, sub-system or assembly
- pulse width/rise time
- conditions of assemblies and components
- open/short circuit
- signal noise/interference levels
Checks to ensure the accuracy and quality of the tests carried out will verify that:
- test equipment is calibrated to specification
- test equipment used is appropriate for the tests being carried out
- test equipment is operated within its specification range
- test procedures used are up to date
Test outcome(s) may be recorded/reported using the following:
- preventative maintenance log/report
- company-specific reporting procedure
- inspection schedule
- specific test report