1.1 How do you tell if electrical equipment is safe to use?
1.1.1 Switchboards
1.1.2 Electrical cables and conduits
1.1.3 Overhead power lines
1.1.4 Power poles
1.1.5 Electrical accessories
1.1.6 Other electrical equipment
Initially, you should visually examine electrical equipment to see whether the power points, light fittings, switchboards, wiring and other electrical equipment appear to be undamaged and in operational condition.
You should pay particular attention to the electrical equipment discussed in the following sub-sections to see if there is any damage, or if the equipment has other readily apparent problems.
If you find any problems, or suspect something is not electrically safe, a licensed electrical contractor or an employee who is a licensed electrical person are the only people permitted to rectify the problems involving electrical work.
You should carry out this visual examination once every 12 months.
1.1.1 Switchboards
Switchboards should be checked to ensure that all switchboard equipment such as fuses, safety switches and circuit breakers are clearly marked to indicate the equipment they control. It should be clear from switchboard marking which circuit breaker or fuse controls particular equipment.
It is important that switchboard marking is correct so that in an emergency, electrical equipment can be quickly isolated.
If you can't identify the fuses, safety switches or circuit breakers and their related electrical equipment or circuits, a licensed electrical person should be called in to mark the switchboard correctly.
There should be no broken parts of switchboards or switchboard equipment that allow access to live parts. For example, figure 1 shows a group of fuses on a section of a switchboard. One of the fuse wedges (the removable part) has been taken out and not replaced.
This means that the live parts within the fuse can be touched, and therefore there is a risk of electric shock. You can replace the fuse wedge without a fuse cartridge or element in it, to make it safe.
Make sure live parts are not touched when performing this task. Take these precautions—turn off all main switches and wear dry rubber soled shoes before replacing the fuse wedge.
Fig. 1
Figure 2 shows a switchboard with a circuit breaker removed, leaving a hole where a person's fingers could touch live and dangerous internal parts of the switchboard. You should have a licensed electrical person repair this. Make sure no contact is made with live parts when carrying out this visual inspection.
Fig. 2
1.1.2 Electrical cables and conduits
Electrical cables and conduits should be checked to see if they are secure and not damaged, or exposed to damage. Cables can be exposed to risk of damage, for example, by being run over by a vehicle, or by exposure to other mechanical damage such as heat and excessive vibration (see figure 3).
Figure 3 shows a conduit which has become detached from its fixings, leaving it free to move. This needs to be repaired by a licensed electrical person.
Fig. 3
1.1.3 Overhead power lines
You should ensure that overhead power lines have not been made unsafe, for example, by buildings or equipment having been located under or near them.
Fig. 4
For example, in figure 4 (above), a silo with a ladder and loading platform has been placed adjacent to an overhead line. This means the safe clearance the line achieved when constructed has changed, and the line now presents a risk to electrical safety.
1.1.4 Power poles
You should ensure that poles which support overhead lines are in a safe condition. Poles should be checked for deterioration, for example, from rot or white ants, every five years. You will need to have pole inspections carried out by someone with the appropriate skills and knowledge.
1.1.5 Electrical accessories
You need to ensure that electrical accessories are not cracked, broken, or otherwise damaged, and do not have malfunctioning parts such as faulty switches (see figure 5). Damaged or otherwise unsafe electrical equipment needs to be repaired by a licensed electrical person.
In figure 5, you will notice that the plate of the power point is cracked and needs to be replaced by a licensed electrical person.
Fig. 5
1.1.6 Other electrical equipment
Other electrical equipment connected to the electrical installation for use should be checked to ensure that:
- there are no broken or damaged parts of the equipment, including controls, cabinets or casings;
- safety related parts, including guards, warning lights or gauges, are operating as designed;
- light fittings do not have broken lamps or bulbs where people can touch live parts (filament of the lamp or bulb); and
- the equipment is not exposed to environmental conditions for which it was not designed. For example, electrical equipment such as water pressure systems that plug into a socket outlet may appear to be designed for exposure to the weather, but some are not. You should check the manufacturer's or agent's advice about this.
If electrical equipment is electrically unsafe, it must only be repaired or replaced by a licensed electrical person, or if it is plug-in equipment, it should be removed from service.
Figure 6 shows that the terminal connection box of the motor is partially detached and may expose live terminals.
Last updated July 16, 2009
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