EMU fundamentals, Electrical fundamentals Flashcards
What does EMU stand for?
Electric Multiple Unit
What are the two types of Comeng trains?
Westcode (older) and Knorr (newer)
What do the letters M and T signify in car numbers?
M = motor car
T = trailer car
What are the six pieces of common cabin safety equipment?
- Fire extinguisher
- First aid kit
- Red/green flags
- Switch stick
- Jumper cables
- Audible Track Warning Devices
Where does a driver sit on a Comeg?
B side
In a Comeng, what side are the power and brake controllers on?
Brake = Left
Power = Right
In a Siemens, what side does a driver sit and where is the master controller located?
Driver sits on B side
Controller located on left
In an X’Trap, where does the driver sit and where is the master controller located?
Driver sits in middle
Master controller on right
In an HCMT, where are the drivers seats, OJT seats, and master controller?
Drivers seat = B side
OJT seat = A side
Master controller = Left
What padlock is used to unlock the Audible Track Warning Devices?
5p key
What is the purpose of the Emergency Track Circuit Jumper Cables?
Short-circuits the track to put the rear signal to the Danger position
How does a driver use the Emergency Track Circuit Jumper Cables?
- Clipping one end onto a rail
- Stretching other end across the five-foot and clipping to the adjoining rail
What is the safety action a driver must make before clipping the second Emergency Track Circuit Jumper Cable?
Brush it against the rail head – if there is excessive arcing/sparking, do not fit to rail.
Compressed air is used on all MTM trains for a variety of purposes throughout pneumatic systems including: (2)
- Braking systems
- Suspension systems
Which train has the most isolating cocks?
Comeng
What are the two common types of isolating cocks?
- Top operated cocks
- Side operated cocks
What are the Yellow and Red isolating cocks called?
- Yellow TECH cock
- Red Emergency Circuit cock
As a general rule, how can you tell a cock is on the open position?
The cock handle will be in line with its corresponding pipe
How are Siemens isolating cocks operated?
By squeezing the spring-loaded release and turning the cock 90 degrees.
How much power is drawn into each train from the overhead wires?
1500v DC
What are three types of connection used in EMU couplings?
Mechanical, pneumatic and electrical connections
Which trains use Scharfenberg couplers?
Comeng and X’Trap
What type of coupler does an X’Trap use?
Scharfenberg
What type of coupler does a Comeng use
Scharfenberg
What type of coupler does an Siemens use?
Dellner
A Dellner coupler is used on which type of train?
Siemens
What type of coupler is used on an HCMT?
Semi-Automatic Coupler
(for rescuing purposes)
What type of coupler is used to connect motor cars to trailer cars?
Semi-Permanent Coupler
Which cars are only fitted with friction brakes?
Trailer cars
Which cars have Electro-Dynamic/Rheo brakes?
Motor cars only
What brakes are common across all types of cars?
Electro Pneumatic (Friction) brakes
What type of brake is unique to the Comeng?
Automatic Air Brake
What is a bogie?
A chassis or framework carrying wheels, attached to a vehicle.
What are the two types of secondary suspension used between the bogie frame and the rail vehicle body?
Coil spring (X’Trap
Rubber air bags (Comeng, Siemens, HCMT)
What is the primary suspension on an EMU and where is it located?
Rubber mounted spring
Located between axle box and bogie frame
Now is a great time to study diagrams of the Comeng and X’Trap Carriage Components on page 15 of EMU fundamentals. Maybe make yourself an unlabelled diagram on a physical flashcard you so you can practice identifying the bits
Okay.
Now is a great time to study diagrams of the Siemens Carriage Components on page 16 of EMU fundamentals. Maybe make yourself an unlabelled diagram on a physical flashcard you so you can practice identifying the bits
Good idea
Now is a great time to study diagrams of the HCMT Carriage Components on page 16 of EMU fundamentals. Maybe make yourself an unlabelled diagram on a physical flashcard you so you can practice identifying the bits
Stop telling me what to do
On the Metro Trains fleet, where would door number 1 be located?
On the “A” side at the number 1 end of the car
How are wheels on each EMU (excluding HCMT) numbered?
8 wheels on each car
Wheel 1 is the wheel located frontmost of the 1 end of the train on the “A” side. Wheels numbers follow a sequential clockwise direction around the car
What is a milliamperes (mA) and an ampere (A)? How many As does a train pull?
An Ampere (A) is the unit of electrical current describing the quantity of the current flow. Example = amount of water flowing in a pipe
An Ampere = 100A, 1mA = .001A)
A train pulls between 4 and 800 A
What are the primary effects of electric shock? (6)
- Shock
- Burns
- Unconsciousness
- Respiration stops
- Reduction of blood circulation
- Death
What must a driver do if they find an electrical shock victim?
- Protect themselves from becoming another victim
- Isolate the source of electricity
Switches can come in many forms including: (6)
- Buttons
- Levers
- Toggle switches
- Dimmer switches (rheostats)
- Pneumatic switches
- Timing switches
When a switch is _______, power is prevented from getting to the equipment
Open (off)
When a switch is ______, energy will pass through the wires and power the equipment
Closed (on)
What form does circuit protection take in all EMUs?
Circuit breakers
What can be the outcome of circuit faults? (3)
- Rapid current increases
- Heat build-up
- Potential fire/destruction
Now is a great time to review the pictures on pages 15/16 of Electrical Fundamentals to view the circuit breakers in each type of train
Okay
Can we use circuit breakers as switches to turn equipment on and off?
No
When can you reset a tripped circuit breaker?
Once you’ve determined the cause of the fault, and it is considered safe to do so
Where do traction motors attach and what do they do?
Attach to drive axles on bogie of a train’s motor car
They convert electrical energy into rotational mechanical force to propel train along track
What do electrical transformers do?
Transform 22 000v AC to 1500v DC via substations
What do alternators do?
Convert a DC power supply to Alternating Current (AC)
(Comeng uses this to power auxiliary equipemnt)
What do rectifiers do?
Converts AC supply to DC supply.
(Used on Comeng to supply 110c DC power supply for Train Cable)
(eg. 1500v DC —> [alternator] —-> 415v AC —–> [rectifier] —-> 110v DC)
Which trains have inverters and what do they do?
Siemens, X’Trap and HCMT trains all have inverters.
They convert 1500v DC to the auxiliary (AC) power supply, and converts power to traction equipment which uses AC power.
Which trains have Rheostatic/Electro Dynamic breaking, and what is it?
All Metro motor cars have Rheo/ED brakes. (Trailer cars do not have them)
Slows train without need for friction brakes.
Traction motors are used as generators to apply retarding force.
Rotational energy is diverted to heat, which is dumped into atmosphere
Generally, how long is each overhead sub-station section?
About 5km long
On EMUs, what are 7 items generally powered by the auxiliary power supply?
- Air Conditioner systems
- Saloon lighting
- Passenger Info displays
- Headlights
- Battery chargers
- Air compressors (not Comeng)
- General power outlets
What is a volt?
Unit of measurement for electrical potential
Describe an Ampere
Quantity of current electrical flow - commonly mentioned in context of applying tractive power to EMU traction units
Describe electrical resistance
The drag present in an electrical circuit that restricts electrical energy from flowing freely
eg. dimmer switch
What is Alternating Current and how many volts are used on MTM trains?
Lol I forgot to define this
415v AC
