Overhead Components and Procedures

Question 1

What is the safe distance from any live component of the Overhead Traction Power System?

Answer 1

2 metres

Question 2

What is the Voltage of the power coming in the sub-station?

Answer 2

22,000 V AC

Question 3

Who manages the overhead system?

Answer 3

Electrol

Question 4

How many times will Electrol try and reset the power supply remotely of there’s loss of overhead power?

Answer 4

2 times

Question 5

Can you use Emergency Track Circuit Jumper Cable on a disarranged overhead?

Answer 5

NO

Question 6

Contact wire must be within a certain height of the rail:

Answer 6

Minimum height under bridges is 4.4 metres
Maximum height is 6 metres
Normal average height will be 5 metres.

Question 7

What are Jumper Feeders and what are they used for?

Answer 7

Heavy gauge copper wires attaching two adjoining Contact wires.
They are attached in the shape of an INVERTED U and are used to conduct electricity from one length of Contact wire across to the next.

Question 8

What are Guy Wires and what are they used for?

Answer 8

Heavy wires attached from Overhead structures to an anchor point in the ground to provide stability to Stanchions where required.
Usually provided for Stanchions where lengths of Catenary or Contact wire are terminated.

Question 9

What is the purpose of Section Insulators

Answer 9

To isolate sections of overhead.

They can also be used to isolate sub-stations from each other.

Question 10

What are the 3 types of Section Insulators?

Answer 10

Fibreglass
Porcelain
Wood

Question 11

Which type of Section Insulator is the most common?

Answer 11

Fibreglass

Question 12

What are the 2 type of Tension Structures?

Answer 12

Spring and Weight

Question 13

Which type of Tension Structure is used on longer sections of overhead?

Answer 13

Weight type

Question 14

How does the weighted tensioner work?

Answer 14

The weight will rise and lower according to the temperature and the heat within the copper wire.
As the wire heats, it expands which will allow the weight to drop to keep it tense.

Question 15

What is Electrolysis?

Answer 15

Process of a power supply causing a chemical reaction with metals and changing their composition.

Question 16

What distance should you stop the train from the Terminating Stop Sign?

Answer 16

3 metres in advance

Question 17

What does a Terminating Stop Sign look like?

Answer 17

White star with black circle in the centre

Question 18

What are examples of events described as Emergency Traction Power Isolation

Answer 18

A person touching or likely to touch any part of the traction power system
A fire on any part of the traction power system
A fire on a train
A damaged component of the system

Question 19

While driving the train, what can the driver observe to see if there’s potential defect in the overhead?

Answer 19

• Look at contact wire - does it have a snake-like effect or appear to sag?
• Observe for obstructions or broken droppers hanging down
• Observe your illuminated Fault lights (traction/air conditioning/motor alternator or static inverters)
• Look back in your mirrors - is the train travelling correctly?

Question 20

If you are unable to stop before reaching damaged or obstructed Overhead equipment, what should you do?

Answer 20

• Lower the train lined pantographs immediately
• Make an Emergency brake application or attempt to coast under the affected area
• Call Train Control and report overhead damage
• Examine pantographs and equipment on the train for damage
• Driver must then decide whether it is safe for the train to proceed.
• Driver must be aware that if the overhead is disarranged, it may not be safe to leave the Driver’s cab.
• In this instance, the driver must make a PA announcement to passengers warning them of the danger.

Question 21

Where are the 3 locations where you’ll find a Tramway Crossing overlapping with a Railway Crossing?

Answer 21

Glenhuntly Road
Riversdale Road
Kooyong - Glenferrie Road