HCMT Pnematics And Brake Systems Flashcards
What is compressed air supplied to?
(9 answers)
• Main Reservoir
• Pantograph
• Air suspension systems
• Electro-Pneumatic Braking Systems
• Trips
• Sanding Equipment
• Couplers
• Horns
• Driver and OJT systems
Main res pressure ?
850 - 1000
Emergency brake cylinder pressure on a HCMT?
280-460
Maximum brake cylinder pressure?
250-380
Holding brake cylinder pressure ?
140-240
Main res over-pressure Saftey valve?
1050
Main res saftey loop activation?
600
What does the ASU consist of?
• Main air compressor
• Air dryers
• Filters
Where are the two compressors for charging the main res located?
B side of Tc cars
When will the auxiliary compressor automatically raise the pantos?
• When there is insufficient MR pressure on the car to raise the local Panto
• When the car has been isolated from the MR system
What are the 3 types of reservoirs on this train?
• Main res
• Surge res
• Brake supply res
Where is the main res located?
B side of every car
What is the purpose of the surge res?
To supply compressed air to the air bag suspension
How many surge reservoirs are fitted to each car?
4
What is the purpose of the brake supply res?
To supply compressed air to the EP valves in the BCM to charge the brake cylinders
How can a Panto be raised?
• MR pressure above 700kpa
• The battery powered auxiliary compressor located on DMp cars will raise the local Panto, when insufficient MR pressure is present
Will the under frame Panto isolating cock isolate the Panto on a DMp car?
No
What does the saloon area Panto isolating cock do in the isolated position?
Isolate the flow of are form the auxiliary compressor to the Panto on DMp cars. The Panto will lower and be isolated so it can’t raise
What is the primary method to reset the trip?
Via the trip reset located in the OJT panel
If you need to isolate the trip due to a fault what cock would you turn and where?
Trip isolating cock which is located on B side between doors number 2 and number 4 on the Tc car
If the trip bypass switch is operated what does it introduce?
The Saftey system bypass acknowledgement button
What does the Post trip speed restriction do?
It restricts the speed of the train by cutting traction Power above 25km/h
How long will the post trip speed restriction apply for?
500 seconds from the time the train commences moving after trip activation unless cancelled by driver
Where is the horn isolation cock located?
Underneath the coupler cover on B side
Where is the Drivers and OJt seat isolation located?
Beneath respective seat
What are the 5 isolating cocks in the BCM on the Tc car?
• Brake supply
• Brake Cylinder End 2
• Brake Cylinder End 1
• Tread scrubber
• sanders
What are the 5 isolating cocks in the BCM in the DMp, Mp and DT cars?
• Brake supply
• Brake Cylinder End 2
• Brake Cylinder End 1
• Park brakes
• sanders
Where are tread scrubbers located?
Tc cars on wheels number 3 and 4
Where are the 3 isolating cocks that will isolate the EP friction brakes?
• The saloon brake supply isolating cock ( one per car located under a seat in cabinet B06 near door 4)
• The Brake Control Module brake cylinder isolating cocks (one per bogie)
• The Brake Control Module brake supply isolating cock (one per car).
When does ED braking become available?
Above 3km/h
If 3 or more bogies are isolated on a 7 car set what will happen?
Train removed from service
What happens During EP braking with up to 2 bogies isolated and brake manager active?
Train will request extra braking efforts and stopping should be similar to normal EP braking
What happens During EP braking with up to 2 bogies isolated and brake manger inactive ?
Each car will brake independently with no additional effort, stopping distance should be close to normal EP braking (within 10%)
What is the brake manager?
The BCU that controls brake management in normal operation and directs other BCUs
It is normal the BCU on the active cab
What happens if ED braking system develops a fault?
EP brake will automatically take over
The TMS will automatically isolate and attempt to reset ED once master controller is in coast
What do brake resistors do?
Absorb energy generated by traction motors and dissipates heat
What is the speed threshold of the holding brake?
0.5
Holding pressure- 140-240
The holding brake will not release unless?
• The safety loop is energised
• Brake demand is not registered
• Traction demand is registered above the defined traction threshold
The saftey loop cannot reset until?
• The train is stationary for more than 3 seconds
• The reason for the emergency brake application is reset
• MC to Max Brake and Reverser to Neutral.
What tasks are linked to the vigilance system?
• Vigilance acknowledge button
• Movement of the master controller
• Activating the horn
• Headlight/wiper/washer switch
• Safety system bypass acknowledge
What % of power/ brake does the task linking system need?
5% with in a 3 second window
Where does brake blending take place?
Between 10km/h and 3km/h
Where are park brakes located?
On the axles of every car except the Tc cars
How do you isolate the park brake?
- Pneumatically isolate park brakes
- Manually release the park brakes
Where are the 2 park brake isolation cocks located?
• The saloon park brake isolating cock (located in cabinet B07 under a seat near door
• the BCM park brake isolation cock
What does the primary suspension system consist of?
Rubber laminated springs
What is the secondary suspension?
Airbags
dampers
Levelling valves
How do you isolate the secondary suspension?
You must isolate both air suspension isolating cocks
