Testing electronic equipment and circuits
Overview
This standard identifies the competences you need to carry out inspections and tests on electronic equipment and circuits, in accordance with approved procedures. You will be required to carry out tests on a range of electronic equipment, such as power supply systems, motor control systems, sensors and actuators, digital circuits and systems, analogue circuits and systems, hybrid circuits and systems, to establish that they functioning at optimal level and to specification. You will be required to carry out inspections and tests which will 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-to-noise ratio / interference levels.
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 for carrying out the required inspections and tests, and will provide an informed approach to applying the necessary test procedures. You will understand the equipment being worked on, the test equipment being used, and the various testing procedures and their application, in adequate depth to provide a sound basis for carrying out the activities safely and correctly and ensuring that the equipment 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 inspection and testing activities, especially those for isolating the equipment and taking the necessary safeguards to protect yourself and others 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:
- work safely at all times, complying with health and safety legislation and other relevant regulations, directives and guidelines
- follow the appropriate procedures for use of tools and equipment to carry out the required tests
- set up and carry out the tests using the correct procedures and within agreed timescales
- complete and store all relevant documentation of the test outcome in accordance with organisational requirements
- review the results and carry out further tests if necessary
- dispose of waste materials in accordance with safe working practices and approved procedures and leave the work area in a safe condition
Knowledge and Understanding
You need to know and understand:
- the health and safety requirements of the area in which the testing activity is to take place, and the responsibility these requirements place on you
- your responsibilities under regulations relevant to the electronic testing activities being undertaken, including the electricity at work regulations
- the isolation and lock-off procedure or permit-to-work procedure that applies to the testing activities (such as electrical isolation, locking off switchgear, removal of fuses, placing of warning notices, proving the isolation has been achieved and secured)
- the isolation procedure(s) unique or specific to the electronic circuits
- the specific safety precautions to be taken when carrying out formal inspection, safety and circuit testing of electronic equipment
- the hazards associated with testing electronic equipment and circuits, and with the equipment that is used, and how to minimise these and reduce any risks
- what constitutes a hazardous voltage and how to recognise victims of electric shock
- how to reduce the risks of a phase to earth shock (such as insulated tools, rubber matting and isolating transformers)
- the importance of wearing protective clothing, and other appropriate safety equipment (PPE) during the testing activities
- the importance of keeping the work area clean, tidy and free from waste and surplus materials
- how the testing activities may affect the work of others, and the procedure for informing them of the work to be carried out
- the procedures and precautions to be adopted to eliminate/protect against electrostatic discharge (ESD)
- how to obtain and interpret drawings, Boolean algebra, truth tables, logic symbols, circuit diagrams, specifications, manufacturers' manuals, test procedures and documents needed to carry out the tests
- the basic principles of how the electronic circuit functions, the operation sequence, the function/purpose of individual units/components, and how they interact
- how to determine the most suitable test points within the circuit
- how to set up and apply the appropriate test equipment
- how to check that tools and equipment are free from damage or defects, are in a safe and usable condition, and are configured correctly for their intended purpose
- how to ensure that test equipment is correctly calibrated
- the various testing methods and procedures, and how to apply them to different operating conditions
- how to analyse test results, and use comparison and sequential techniques
- the environmental control requirements and organisation operating procedures relating to functional testing
the documentation required, and the procedures to be followed, at the conclusion of the test
the extent of your own authority and to whom you should report if you have problems that you cannot resolve
Scope/range
Carry out all of the following during the testing activities:
- plan the inspection and testing activities to cause minimal disruption to normal working
- obtain and use the correct issue of organisational and/or manufacturers' drawings and maintenance documentation
- adhere to procedures or systems in place for risk assessment, COSHH, 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 testing area
- carry out the inspection and testing activities using appropriate techniques and procedures
- take electrostatic precautions when handling sensitive components and circuit boards
- re-connect and return the equipment to service on completion of the testing activities
- dispose of waste materials in accordance with safe working practices and approved procedures and leave the work area in a safe condition
Carry out inspections and tests on four of the following types of electronic equipment:
- power supplies (such as switch mode, series regulation, shunt regulation)
- motor control systems (such as closed loop servo/proportion, inverter control)
- sensors and actuators (such as linear, rotational, temperature, photo-optic, flow, level, pressure)
- digital circuits and systems (such as programmable controller, microprocessor, ROM/RAM, logic gates)
- analogue circuits and systems (such as frequency modulation/demodulation, amplifiers, filters, oscillators)
- hybrid circuits and systems (such as analogue to digital convertors [ADC], d-to-a convertors [DAC])
- power supply systems (such as switched mode, series regulation, shunt regulation)
Carry out tests using a range of tools and test equipment, to include three of the following:
- oscilloscope
- signal tracer
- computer-aided diagnostic equipment
- ammeter
- signal generator
- special purpose testing equipment
- logic analyser
- multimeter
- temperature measuring devices
- logic probe
- automatic test equipment
Carry out all of the following tests/measurements, as applicable to the equipment being tested:
- logic states
- pulse width/rise time
- frequency modulation/demodulation
- DC voltage/current levels
- open/short circuit
- performance of circuit
- AC voltage/current levels
- resistance
- condition of assemblies and components
- clock/timer switching
- heat dissipation
- signal noise/interference levels
Carry out all of the following checks to ensure the accuracy and quality of the tests carried out:
- the test equipment is correctly calibrated
- test equipment used is appropriate for the tests being carried out
- take applicable precautions to avoid damaging equipment or components
- test procedures to be used are up-to-date and follow laid-down procedures
- test equipment is operated within its specified range
Complete and store all relevant documentation of the test outcome in accordance with organisational requirements, using one of the following:
- preventative maintenance log/report
- inspection schedule
- organisational-specific reporting procedure
- specific test report
- electronic reports