Carrying out maintenance on instrumentation and control equipment
Overview
This standard identifies the competences you need to carry out corrective maintenance activities to instrumentation and control equipment, in accordance with approved procedures. This will involve dismantling, removing and replacing instruments and faulty peripheral components on instrumentation and control equipment, such as pressure, flow, level and temperature instruments, fiscal monitoring equipment, fire and gas detection and alarm systems, industrial weighing systems, speed measurement and control systems, vibration monitoring equipment, nucleonics and radiation measurement, telemetry systems and emergency shutdown systems.
Your responsibilities will require you to comply with organisational policy and procedures for the maintenance activities undertaken, and to report any problems with these activities, or with the instrument system, tools or equipment used, that you cannot personally resolve, or are outside your permitted authority, to the relevant people. You will be expected to work to instructions, alone or in conjunction with others, taking personal responsibility for your own actions, and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will be sufficient to provide a sound basis for your work, and will enable you to adopt an informed approach to applying maintenance procedures to instrumentation and control equipment and systems. You will have an understanding of dismantling and reassembly methods and procedures, and their application. You will know how the equipment functions and the purpose of individual components, in adequate depth to provide a sound basis for carrying out any repair or adjustment. In addition, you will have sufficient knowledge of these components to ensure that they are fit for purpose and meet the specifications, thus providing a sound basis for carrying out reassembly. You will also know about the interaction of the other associated integrated technologies, and will have sufficient knowledge to carry out the dismantling and reassembly of the instrumentation system safely and effectively.
You will understand the safety precautions required when carrying out the maintenance activities, especially those for isolating the equipment. You will be required to demonstrate safe working practices throughout, and will understand your responsibility for taking the necessary safeguards to protect yourself and others in the workplace.
Performance criteria
You must be able to:
- work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
- follow the relevant maintenance schedules to carry out the required work
- carry out the maintenance activities within the limits of your personal authority
- carry out the maintenance activities in the specified sequence and in an agreed timescale
- report any instances where the maintenance activities cannot be fully met or where there are identified defects outside the planned schedule
- complete relevant maintenance records accurately and pass them on to the appropriate person
- dispose of waste materials in accordance with safe working practices and approved procedures
Knowledge and Understanding
You need to know and understand:
- the health and safety requirements of the area in which the maintenance activity is to take place, and the responsibility they place on you
- the isolation and lock-off procedure or permit-to-work procedure that applies to the system and instruments being worked on, and how to check that any stored energy in pipework and instruments has been released
- the specific health and safety precautions to be applied during the maintenance process, and their effects on others
- what constitutes a hazardous voltage and how to recognise victims of electric shock
- the importance of wearing protective clothing and other appropriate safety equipment (PPE) during the maintenance activities, and where this can be obtained
- the procedures and precautions to be adopted to eliminate electrostatic discharge (ESD)
- how to reduce the risks of a phase to earth shock (such as insulated tools, rubber mating and isolating transformers)
- the hazards associated with carrying out maintenance activities on instrumentation and control systems (such as handling fluids, stored pressure/force, electrical supplies, process controller interface, using damaged or badly maintained tools and equipment, not following laid-down maintenance procedures), and how they can be minimised
- how to obtain and interpret information from job instructions and other documents needed for the maintenance activities (such as drawings, circuit and physical layouts, charts, specifications, manufacturers' manuals, history/maintenance reports, graphical electrical symbols, BS7671/IET wiring regulations)
- the basic principles of operation of the instrumentation being maintained, and its operating sequence
- the reasons for making sure that control systems are isolated or put into manual control, and that appropriate trip locks or keys are inserted, before removing any sensors or instruments from the system
- the correct way of fitting instruments to avoid faulty readings (such as caused by head correction, poor flow past the sensor, blockages, incorrect wiring, poor insulation or incorrect materials)
- how to carry out visual checks of the instruments (such as security of joints and physical damage)
- the procedure for obtaining replacement parts, materials and other consumables necessary for the maintenance process
- the techniques used to dismantle/assemble integrated equipment (such as release of pressures/force, proof marking to aid assembly, plugging exposed pipe/component openings, dealing with soldered joints, screwed, clamped and crimped connections)
- methods of attaching identification marks/labels to removed components or cables, to assist with reassembly
- methods of checking that components are fit for purpose, and the need to replace batteries, boards and other failed items
- 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
- the generation of maintenance documentation and/or reports following the maintenance activity
- the equipment operating and control procedures to be applied during the maintenance activity
- the problems that can occur during the maintenance of the instrumentation and control system, and how they can be overcome
- the organisational procedure to be adopted for the safe disposal of waste of all types of materials
- the extent of your own authority and to whom you should report if you have problems that you cannot resolve
Scope/range
Scope Performance
Carry out all of the following during the maintenance activities:
- undertake the maintenance activities to cause minimal disruption to normal working
- use the correct issue of maintenance documentation (such as drawings, manuals, maintenance records, schedules)
- adhere to procedures or systems in place for risk assessment, COSHH, personal protective equipment and other relevant safety regulations
- ensure the safe isolation of equipment (such as mechanical, electricity, gas, air or fluids)
- ensure that safe access and working arrangements have been provided for the maintenance area
- carry out the scheduled maintenance tasks, using appropriate techniques and procedures
- re-connect and return the equipment to service on completion of the maintenance activities
- dispose of waste items in a safe and environmentally acceptable manner
- leave the work area in a safe and tidy condition
Carry out maintenance activities on one of the following types of instrumentation and control system:
- fire detection and alarm system
- gas detection and alarm system
- emergency shutdown systems
- speed measurement/control system
- fluid measurement/control system
- noise and vibration monitoring/control systems
- nucleonic and radiation systems
- telemetry systems
- temperature measurement/control systems
- weight measurement/control systems
Carry out all of the following maintenance activities:
- making all required isolations (such as process, electrical, pneumatic)
- taking electrostatic discharge (ESD) precautions (where appropriate)
- disconnecting supply/signal connections
- removing instruments from the system
- dismantling equipment to the required level
- labelling/marking of components
- replacing or repairing damaged/defective components (such as electrical, mechanical and back-up batteries)
- checking components for serviceability
- replacing all 'lifed' items (such as seals, gaskets)
- setting, aligning and adjusting components
- tightening fastenings to the required torque
- re-connect instrumentation pipework and power supply
- check signal transmission is satisfactory
- functionally testing the maintained equipment
recording the results of the maintenance activity
16.
reporting or taking action with regard to any defects that require immediate attention (such as replacing non-'lifed' components)
Use two of the following types of instrumentation test and calibration equipment:
- signal sources
- standard test gauges
- analogue and digital meters
- digital pressure indicators
- calibrated flow meters
- special-purpose test equipment
- pressure sources
- comparators
- manometers
- current injection devices
- calibrated weights
- logic probes
- temperature baths
- workshop potentiometers
- dead weight testers
- insulation testers
Maintain installation and control systems in accordance with one of the following:
- organisational guidelines and codes of practice
- equipment manufacturer's operation range
- company regulations
- BS, ISO and/or BSEN standards
Complete one of the following maintenance records and pass it to the appropriate person:
- job cards
- permits to work/formal risk assessment
- maintenance log and action report
- company-specific documentation