This unit standard replaces unit standard 13682, "Maintain Direct Current (DC) machines", Level 4, 5 credits.
Supplementary information:
Specified requirements:
Specified requirements include legal and legislative specific requirements and are contained in one or more of the following documents:
Mines and Minerals Act.
Work site procedures.
SANS specifications.
Manufacturer's manuals.
Applicable statutory requirements:
Glossary of terms:
Advantages and disadvantages of DC machines, control gear and related component may include but are not limited to:
Price.
Availability.
Expected life span.
Delivered power.
Affected parties may include but are not limited to:
Production.
Energy control section.
Buying policy may include but are not limited to:
Hand driven system.
Computer driven system.
Cleaning may include but are not limited to:
Washing with safety solvent.
Washing with cleaning agents.
Wipe with a cloth.
Using compressed air.
Communications and teamwork principles may include but are not limited to:
Questions and answers.
Discussions.
Depending on the help of somebody else to do a job.
Construction of DC machines and control gear may include but are not limited to:
Armature/commutator.
Field coils.
Brushes and brush gear.
Frame.
Consumables may include but are not limited to:
Strapping.
Cleaning agents.
Stationary.
Corrective actions may include but are not limited to:
Repair.
Initiate repairs.
Report to responsible person.
Defects may include but are not limited to:
Cracks in frame.
Broken off pieces.
Broken fan.
Bended shaft.
Open or broken covers (Coupling, machine, terminal boxes).
Noisy bearings.
Worn brushes.
Commutator (Uneven surfaces, hot spots, mushroom segments).
Dismantling may include but are not limited to removing of:
Fan.
Fan cowling.
Coupling.
Covers (Coupling, machine, terminal boxes).
Brushes and brush gear.
Supply cable.
Documentation may include but are not limited to:
Checklists.
Job cards.
Environmental practices may include but are not limited to correct methods of disposing of material containing:
Grease.
Safety solvent.
Cleaning agents.
Factors to consider while doing maintenance on DC machines (maintenance hints) may include but are not limited to:
Use the correct voltage.
Read the name plate (Type of machine, shunt-, series-, compound).
Check and use correct type/size of brushes.
Check brush pressure.
Check commutator (Mica, mushroom segments).
Isolate before commencing any work on machinery.
Washing machine with safety solvent.
Use compressed air to clean machine.
Do not clean commutator unnecessary (Protective platinum film).
Make sure that all covers are closed.
Do not use silicon rubber to seal covers.
Fault diagnosis may include but are not limited to identifying:
Loose terminal connections.
Damaged cable insulation.
Cracks in frame.
Broken off pieces.
Broken fan.
Loose covers.
Bended shaft.
Noisy bearings.
Worn brushes.
Sparks on brushes.
Commutator (Uneven surfaces, hot spots, mushroom segments).
Good housekeeping practices may include but are not limited to practices given by:
NOSA.
Work site procedures.
Hazardous areas may include but are not limited to:
Petrol pumps.
Spray painting booths.
Areas for the storage and use of flammable fuels, paints or solvent.
Flower mills.
Coal cellars.
Wine cellars.
Hazardous conditions may include but are not limited to:
Poor lighting.
Exposed drive coupling of adjacent machine (If in operation).
Slippery surfaces.
Ingress protection rating may include but are not limited to:
Protection of persons against access to hazardous parts.
Protection against water.
Mechanical protection.
Job instruction may include but are not limited to instructions from:
Job cards.
Team leader (Verbal instructions).
Job instruction format may include but is not limited to:
Written or verbal form.
Formal or informal methods.
Maintenance procedure may include but are not limited to:
Manufacturers` maintenance manuals.
Company maintenance manuals.
Manufacturers` specifications may include but is not limited to:
Dimensions of components.
Weight of components.
Type of material from which components were manufactured as given in: manufacturers` maintenance manuals; manufacturer catalogues; company maintenance manuals.
Materials may include but are not limited to:
Bolts and nuts.
Shim stock.
Measuring instruments (electrical) may include but are not limited to:
Multi meter.
Voltage tester.
Clamp meter.
RCL meter.
Oscilloscope.
Recorder.
Obstructive conditions may include but are not limited to:
Equipment blocking the work area.
Structures.
Obtained may include but are not limited to getting job done by somebody else by:
Reporting to team leader.
Reporting to planner.
Placing an order to another section.
On the job faultfinding may include but are not limited to:
Faultfinding on a single phase system.
Faultfinding on a three-phase system.
Organised may include but are not limited to:
Placing of DC machine components, material, work platforms and consumables on strategic places for safe, quick and easy use.
Positioning of DC machine components, material, work platforms and consumables in the sequence that it is going to be used.
Personnel protective equipment may include but are not limited to:
Safety glasses.
Safety belts.
Visors.
Helmets.
Safety shoes.
Personal safety may include but are not limited to:
Assuring safe conditions as given by NOSA.
Acting safely as given by NOSA.
Planed maintenance may include but is not limited to:
Cleaning (Blow out machine with compressed air).
Inspecting of components (Armature, brushes and brush gear, commutator, frame, sparks on brushes).
Poisonous, toxic and dangerous materials may include but are not limited to:
Grease.
Safety solvent.
Cleaning agents.
Policy procedure may include but are not limited to:
Methods of communicating.
Methods of completing documentation.
Methods of selecting personal safety equipment, tools, consumables, etc.
Checklists.
Practical safety may include but are not limited to:
Using of personnel protective equipment.
Processed may include but are not limited to:
Handed to team leader.
Posted to planner.
Filed.
Reassembling, adjusting and testing may include but are not limited to:
Reversal of dismantling.
Testing machine according to SANS 10142-1 section 8.
Recyclable material may include but are not limited to:
Scrap paper.
Boxes.
Reporting system may include but is not limited to:
Documentation (electronic of paper).
Verbal feedback.
Removing may include but is not limited to:
Disconnecting cable.
Undoing of base bolts.
Carry or transport machine to working facility.
Routine maintenance may include but is not limited to:
Check for excessive vibration.
Check for sparks on the brushes.
Abnormal noises from machine (Bearings).
Open covers.
Safety will include but are not limited to:
Personal safety.
Practical safety.
Safety on equipment.
Safety on equipment may include but are not limited to:
Heavy weight of machines.
Slings.
Eye bolts.
Scrap material may include but are not limited to:
Bolts.
Nuts.
Used sand paper.
Special electrical measuring instruments may include but are not limited to:
Growler.
Tacho generator.
Specialist information may include but are not limited to:
Staggering of brushes.
Special work platforms may include but are not limited to:
Scaffolding.
Telescoping scaffolding.
Lift truck.
Statutory requirements may include but is not limited to:
OHS Act.
SANS 10142-1.
Local Authority requirements.
Supervise may include but are not limited to:
Inspect quality of work done.
Identifying hazards.
Writing of procedures.
Explain procedures.
Team leader may include but are not limited to:
A qualified machine maintainer.
Supervisor.
Superintendent.
Tools may include but are not limited to:
Hand tools.
Power tools.
Measuring instruments (Electrical and Mechanical).
Work area may include but are not limited to:
Offices.
Workshops.
Processing machinery.
Working facility may include but are not limited to:
Work bench.
Machine test table.
Work platforms may include but are not limited to:
Stepladders.
Ladders.
Work site procedures may include but are not limited to company`s:
Safety procedures as given in safety manuals.
Policy procedures as given in policy manuals.
Installing procedures as given in manufacturers` and company maintenance manuals.
Maintaining procedure given in manufacturers` and company maintenance manuals.
Context specific:
User manuals supplied by manufacturers.
Specifications, agreements and policies and procedures. |