ELECTRICAL MAINTENANCE SKILLS (INDUSTRIAL)

COURSE 110: 12 DAYS

This course is designed to provide basic electrical skills to those who need to perform first-line electrical maintenance tasks – including the safe isolation, replacement and testing of a range of common electrical devices (motors, sensors, heating elements, solenoids, etc.) – in a safe and effective manner. Importantly, the format of the course is specifically designed so that, when combined with suitable on-site consolidation of training, it will assist the maintenance manager in meeting the legal requirements for employee competence in electrical work.

PARTICIPANTS

No prior electrical knowledge is assumed. The structure and content of the course is aimed at those who currently fulfil a maintenance role, for example mechanical fitters. Many companies use this course to help introduce flexibility to their workforce, as part of a multiskilling programme.

Candidates with previous electrical experience (for example instrument engineers, electronics engineers, or those that have gained the necessary knowledge of electrical principles from elsewhere can attend a shortened version of this course: please see Course 120: Electrical Maintenance Skills for Instrumentation Personnel.

COURSE PRESENTATION

One of the practical exercises that candidates perform on the Electrical Maintenance Skills Course: Measuring the winding resistance of three-phase motors to determine their serviceability

The course has an extensive ‘hands-on’ practical approach, placing emphasis on safe working practice and on the development of useful, practical skills. Comprehensive course notes are provided.

COURSE OBJECTIVES

On completion of the course, participants will be able to

practice safe working methods on electrical systems
understand the relevant regulative requirements
demonstrate an understanding of electrical principles and units
identify a wide range of electrical equipment & devices and understand their principles of operation / connections
understand the principles of earthing / protection and associated protective devices
demonstrate an understanding of electrical systems, switchgear and circuit types
work with a range of cable types and carry out correct terminations and connections
recognise the most common industrial motor types and understand their operation, connections and maintenance requirements
use electrical test equipment effectively and carry out testing of a range of motors, solenoids, cables, etc. (using insulation, continuity, tong testers, etc.)
identify motor and power circuit faults
use circuit diagrams as an aid to maintenance
take precautions when resetting overloads etc
perform electrical isolation, testing for dead, etc on a wide range of devices and circuits safely.

Successful completion of the course leads to the award of Unite / Technical Training Solutions competence certificate 110: Electrical Maintenance Skills (Industrial).

The Consolidation Scheme allows candidates to practice their new skills at work, generating all the necessary evidence for their competence
This course is particularly suitable for the on-site consolidation scheme, which enables candidates to practice their newly acquired skills in the workplace. For more information on the scheme, please contact us.

Contact us for more information on how the electrical maintenance skills training course leads to competence in performing first-line electrical work such as competently isolating single-phase and three-phase systems and removing and replacing electrical devices

What do candidates on the industrial electrical maintenance skills course actually do?

During Week 1 of the course, candidates learn about basic electrical principles. This grounding in the fundamental concepts ensures a full understanding of the technical and safety issues in the later stages of the course.

Candidates learn in a practical way about ohm's law, series and parallel circuits etc, seeing at first hand what the relationships are between voltage, current and resistance. The following are some example of the course notes for this part of the course, describing ohm's law, series and parallel circuits and solenoids, relays and contactors:

This is page 12 of Part 1 of the electrical maintenance skills training course notes, describing ohm's law This is page 20 of Part 1 of the electrical maintenance skills training course notes, describing series and parallel circuits this is page 26 of Part 1 of the electrical maintenance skills training course notes, describing solenoids and relays

We ensure that this part of the course is kept interesting and relevant to the objectives of the course by avoiding any unnecessary theory and introducing some commonly-used industrial components, whilst using multimeters to make measurements, exploring the basic electrical principles as they go. To achieve this we have constructed exercise boards with industrial switches, sensors, relays, contactors etc so that they can build circuits, make measurements using digital multimeters, gain familiarity with the components and learn about the principles in a structured, interesting and enjoyable way.

Our custom-designed basic circuits rig allows candidates to build basic electrical circuits and learn about electrical principles whilst familiarising themselves with the basic electrical components in week 1 of the electrical maintenance skills training course

In the first week of the electrical maintenance skills course candidates also study the common industrial electrical components that they are likely to encounter - proximity detectors, relays, thermocouples, Pt100s and others. More complex circuits incorporating these components are constructed on the basic circuits board shown above. They also have an in-depth briefing of the effects of electric shock - a key issue on this course, as we need to be confident that they are aware of the potential dangers. The following are example pages from this part of the course notes for the electrical maintenance skills course, describing proximity detectors, relays and the effects of electric shock:

This is page 39 of part 1 of the electrical maintenance skills training course notes, describing proximity detectors This is page 43 of part 1 of the electrical maintenance skills training course notes, describing relays This is page 50 of part 1 of the electrical maintenance skills training course notes, describing the effects of electric shock

In Week 2 of the electrical maintenance skills course the candidates build on the fundamentals by learning about electrical dangers and protection methods; the principles of earthing, how the effects of electric shock are reduced, fuses, circuit breakers, RCDs and other related issues. They also learn about the Electricity at Work (EAW) Regulations and how these might affect their future work - exploring issues like live-working, competency, etc. The following are example pages from this part of the course notes for the electrical maintenance skills course, describing how insulation resistance testers should be used, how electrical systems should be isolated (getting the candidates to think through the various stages necessary) and an excerpt from the fault-finding part of the course, where we teach the candidates how to go about finding common faults like open circuits, short circuits and earth faults in industrial electrical circuits:

This is page 22 of part 2 of the electrical maintenance skills training course notes, describing insulation and continuity testing This is page 36 of part 2 of the electrical maintenance skills training course notes, describing isolation procedures This is page 44 of part 2 of the electrical maintenance skills training course notes, describing fault-finding methods

We teach the candidates the right way to prepare and terminate cables into plugs and sockets and how to use professional crimp tools to crimp conductors properly.

Candidates also learn why and how insulation and continuity testers are used, for which we have developed simulation units so that once they are able to use the testers properly to check cables, accessories and current-using equipment, they then apply their skills to finding open circuits, short circuits and insulation breakdowns within specially constructed test circuits. This allows them to gain some basic electrical faultfinding skills, developing their skills and understanding of the fundamentals further.

We also explain the effects of overload, short circuit and earth faults in electrical systems, showing how the various protective devices like fuses, circuit breakers and RCDs operate. We have a specially-constructed training rig for this also, so that candidates can explore these important issues.

The following are examples of the fault-finding training rigs (where candidates diagnose faults in the control and load circuits of industrial electrical circuits), the tools that the candidates use on the electrical maintenance skills course for terminating cables, the training rig used for exploring the effects of short circuits, overloads and earth faults, the rig used for the cable termination exercise, one of the insulation resistance testers used and examples of some of the leads that candidates build on the course:

The faultfinding test board used on the electrical maintenance skills training course We provide the candidates with all the necessary tools during the electrical maintenance skills training course The electrical fault board used on the electrical maintenance skills training course - this is used to explain what happens when short circuits, earth faults and overloads occur

This is the cable termination rig used on the electrical maintenance skills training course We use professional insulation resistance / continuity testers on the electrical maintenance skills training course Examples of some of the leads that candidates construct on the electrical maintenance skills training course

We then teach the candidates about three-phase motors: how they work, identification features, terminal configuration, testing, etc, whilst using their knowledge of voltage, current and resistance to understand the principles of induction.

This is page 65 of part 2 of the electrical maintenance skills training course notes, describing the key features of cage induction motors This is page 69 of part 2 of the electrical maintenance skills training course notes, describing the information found on the nameplates of industrial motors This is page 73 of part 2 of the electrical maintenance skills training course notes, describing the configuration of the terminals of a delta-linked motor

In Week 3 we explain the various standards of symbols used on industrial circuit diagrams and look at the function of the most common components found in control panels - contactors, overload relays, etc. The following are example pages from this part of the electrical maintenance skills course, describing electrical symbols, contactors and overload relays:

This is page 7 of part 3 of the course notes for the electrical maintenance skills training course, describing the various electrical symbols used on drawings for a range of common Standards This is page 10 of part 3 of the course notes for the electrical maintenance skills training course, describing how contactors are used This is page 13 of part 3 of the course notes for the electrical maintenance skills training course, describing how overload relays are used

We then introduce industrial control panels with DIN-rail mounted components like circuit breakers, fuses, contactors, overload relays, timers, switches and lamps. The candidates build some basic industrial electrical circuits - for example from simple DOL to star/delta motor starters - giving them the experience of recognising each of the components, their markings and terminal identifications, the differences between the load and control circuits etc, in an engaging way that they really enjoy. The following are the three-phase 40V motors we use, the empty control panel (before candidates have assembled their circuits) and the components that they use to build the circuits:

This is one of the specially-wound 40 volt three-phase motors used on the electrical maintenance skills training course We have designed a special training rig so that the candidates actually build the circuits that we give them, using real industrial components, following the circuit diagrams provided in week 3 of the electrical maintenance skills training course Candidates are provided with a range of industrial circuit breakers, contactors, timers and overload relays with which to build the circuits that we give them in week 3 of the electrical maintenance skills training course

Reading circuit diagrams and translating them to real components is a key objective of the course. The best method for learning about this is to engage the candidates in an enjoyable way and therefore we provide the candidates with (amongst others) the following example circuits which they build into the panels shown above:

This is page 14 of part 3 of the course notes for the electrical maintenance skills training course, describing how DOL starters work - candidates build this circuit in the panels shown above This is page 45 of part 3 of the course notes for the electrical maintenance skills training course, describing star/delta starters - candidates build this circuit in the panels shown above This is page 46 of part 3 of the course notes for the electrical maintenance skills training course, describing a complex control circuit diagram - candidates build this circuit in the panels shown above

The candidates can then (before connecting these circuits to our custom-manufactured 3-phase 40 Volt motors) inspect and test their prepared units, ensuring that the circuits have been interpreted correctly. We have developed a three phase 40-volt ac supply to power these systems so that all this can be done safely. The following are examples of our 40 volt three-phase supply units, one of the control panels assembled and ready for the candidates to wire up, and our testing for dead instruments:

This is our specially-designed three-pase 40 Volt ac supply: It generates its output from a single-phase mains supply, so that we can provide the course without needing a three-phase supply for the electrical maintenance skills training course One of the control panels, ready for wiring by the candidates on the electrical maintenance skills training course Candidates use professional voltage testers and proving units on the electrical maintenance skills training course

The above units can then be powered-up to check for their correct functionality. Any faults need to be rectified and candidates gain valuable experience of faultfinding in real industrial control panels during this exercise.

Once the systems are working correctly we can then explore various scenarios in which candidates work out how a safe isolation should be performed on their systems. We can simulate a variety of scenarios, including situations in which the system has local and remote start/stop and local and remote isolators. Candidates give their written explanation (a method statement of work) for how they intend to do this and once they have written it correctly we ask them to perform it for real on the systems that they constructed earlier.

The above exercise is one of the focal points of the course as it brings together not only the candidate's ability to perform an electrical isolation but also their use of voltage testers, recognition of the various components, an understanding of the system etc.

We then replace some of the components in the candidates' functional systems with faulty components like burned out contactors, faulty overload relays, incorrect contactor coil voltages, faulty auxiliary contacts etc. Candidates then fault-find the systems to diagnose the faults.

If you would like to see some of the equipment used on the industrial electrical maintenance skills course for yourself, then please call us to arrange a visit to our offices in Kent. Alternatively, we can visit you anywhere in the British Isles.