Train Pneumatics

Question 1

What components make up the air systems? (9)

Answer 1

Two air compressors
Compressor Governor
Compressor Governor I.C.
Air dryers
Main Reservoir
Auxiliary Reservoir
Main Reservoir Pipe
Auxiliary Pneumatic Panel
Brake Pipe

Question 2

What is Main Reservoir pressure?

Answer 2

750 - 900 kPa

Question 3

What pressure does the Main Reservoir safety valve operate at?

Answer 3

980 kPa

Question 4

What is BP pressure on normal operation?

Answer 4

0 kPa

Question 4

At what Main res pressure will emergency brakes apply?

Answer 4

580 kPa

Question 5

What is BP pressure on rescue operation?

Answer 5

550 kPa

Question 6

What is Holding BC Pressure?

Answer 6

120 kPa

Question 7

What is full service BC Pressure?

Answer 7

190 kPa

Question 8

What is Emergency BC pressure?

Answer 8

210 kPa

Question 9

When do both air compressors operate?

Answer 9

When pressure is below 650 kPa both operate

When pressure builds to 750-900kPa one will switch off

Question 10

What pressure does the compressor Governor maintain Main Reservoir pressure at?

Answer 10

750-900 kPa

Question 11

What happens to air compressors if compressor Governor is isolated?

Answer 11

If on they will stay on

If off they won’t come on

Question 12

What does the Main Reservoir system supply compressed air to? (4)

Answer 12

Friction Braking system (aux. res)
Trip
Whistle/horn
Pneumatic auxiliary panel

Question 13

What does the auxiliary reservoir do?

Answer 13

Supplies air to EP (friction) brakes

Air supplied via valves to BCs

Question 14

What does the Main Reservoir pipe connect from/to?

Answer 14

Main Res air to

Auxiliary Res. (Mc Tp)
Auxiliary Pneumatic Panels (Mc)
Scharfenberg Coupler (Mc)
SPBs (Mc)

Question 15

Where is the primary suspension
Vs
Secondary suspension?

Answer 15

Primary - between axle and bogie
Secondary - between bogie and carriage

Question 16

What does the secondary suspension consist of?

Answer 16

Rubber mounted spring
Bump stoppers - lateral m’vmnt
Vertical dampers
Lateral dampers

Question 17

What are the four braking systems in an XTrap?

Answer 17

Service brake
Holding brake
Emergency brake
Spring park brake

Question 18

What is the service brake made up of?

Answer 18

ED & EP

Question 19

When does EP brake operate?

Answer 19

At low speed when ED is ineffective

During wheel slide events

Question 20

What EP equipment do Mc’s have
Vs
Equipment that Tp’s have?

Answer 20

Mc - 1 tread brake per wheel
1 disc per axle

Tp - 1 tread brake per wheel

Question 21

What do Friction Brake Indicator lights show?

Answer 21

Red if friction / EP applied.

Green if friction / EP released

Question 22

Which cars to ED brakes operate on?

Answer 22

Mc

Question 23

When do ED brakes operate?

Answer 23

Above 10 kmh

Question 24

When does brake blending occur?

Answer 24

5-10kmh

Question 25

When does ED brake become ineffective?

Answer 25

5kmh

Question 26

When does Holding Brake apply?

Answer 26

When train speed falls below 0.5kmh EP releases - holding brake automatically applies

Question 27

What is BC Holding brake pressure?

Answer 27

120 kPa

Question 28

When does Holding Brake release?

Answer 28

When traction power is obtained

Question 29

What is emergency brake pressure?

Answer 29

210 kPa

Question 30

When does emergency brake apply?

Answer 30

When MCH is placed to emergency Emergency stop button activated in any cab Safety loop being de-energised (open)

Question 31

Where are SPBs located?

Answer 31

Wheels 1, 3, 7 on Mc cars inly

Question 32

How are SPBs applied?

Answer 32

Automatically as main res air depletes to 350 kPa

Question 33

How do SPBs release?

Answer 33

Automatically as main res air increases

Question 34

Can SPBs be applied manually?

Answer 34

No

Question 35

Can SPBs be released manually?

Answer 35

Yes Unlock and pull handle

Question 36

What are the Emergency Mode Switch (EMS) Switch positions?

Answer 36

1 online holding brake inhibit 2 normal 3 rescued 4 rescuing 5 rescuing in propulsion

Question 37

How do you charge the BP?

Answer 37

With EMS in 3, 4, or 5 both trains place MCH to full service brake position

Question 38

When will BP pressure cause safety loop to open?

Answer 38

Below 300 kPa

Question 39

At what BP pressure will safety loop close allowing emergency brake to release?

Answer 39

430 kPa