Basic Electrical

Question 1

What is the safe approach distance for a fallen distribution line and a transmission line?

Answer 1

Distribution line - 8M
Transmission line - 20M

Question 2

List 5 hazards that may be present at a substation?

Answer 2

◼Compressed Gas
◼High voltage (HV)
◼ Polychlorinated biphenyls (PCBs) in transformers and capacitors
◼ Residual power after isolation – in the capacitor banks
◼ Oils used for cooling – use foam to extinguish.
◼ Stairs close to entry
◼ Confined space

Question 3

What is non-contact AC Voltage tester used for?

Answer 3

The non-contact voltage detector is used to, but is not limited to:
◼ Determine the location of electrical hazards at structure fires by firefighters tasked to
enter a scene where POWER has not been isolated.
◼ To determine, after power has been isolated, that other sources of power such as
illegal electrical connections, are not present.
◼ Identify whether a component, such as metal fencing, street furniture, or anything in
contact with it, is energised