Electrical Awareness Flashcards
What does “alive/live” mean?
A complete circuit that allows electricity to flow
What does “de-energised” mean?
An electrical circuit that is disconnected from all sources of supply, but not necessarily isolated, earthed or out of commission.
What does “isolated” mean?
An electrical circuit with a visible break that stops the flow of electricity
What does “automatic/remote re-closure” mean?
The automatic and manual operation of substation circuit breakers. These circuit breakers can de-energise and re-energise a circuit without warning after a fault
What is the voltage for a tram and a train?
Tram 600 volts
Train 1500 volts
What is step potential?
When feet are placed on different voltage rings, electricity equal to the difference between the rings will flow through the body
What is the ripple effect?
When an energised wire comes into contact with the ground, it energises the ground surrounding it. This creates a ripple effect from the point of contact outwards
What is touch potential?
When touching a wire or energised object while standing with feet on the same voltage rings, voltage equal to the difference between the wire and the voltage ring will flow through the body
What is the safe approach distance for distribution power lines and transmission power lines?
Distribution 8m
Transmission 20m
What are the actions to be taken for a fallen powerline?
Notify the power company asap
Restrictive tape
Always maintain safe approach distance of at least 8m
Notify FIRECOM
Police traffic control
Never touch wires, even if proven to be isolated
Treat all wires as live
What actions would you take at a kiosk incident?
Request power company attendance asap
Maintain a safe approach distance of 8m
Evacuate the area
Protect exposures
Do not attempt to extinguish until isolated by the power company
