Train Pneumatics Flashcards
What components make up the air systems? (9)
Two air compressors
Compressor Governor
Compressor Governor I.C.
Air dryers
Main Reservoir
Auxiliary Reservoir
Main Reservoir Pipe
Auxiliary Pneumatic Panel
Brake Pipe
What is Main Reservoir pressure?
750 - 900 kPa
What pressure does the Main Reservoir safety valve operate at?
980 kPa
What is BP pressure on normal operation?
0 kPa
At what Main res pressure will emergency brakes apply?
580 kPa
What is BP pressure on rescue operation?
550 kPa
What is Holding BC Pressure?
120 kPa
What is full service BC Pressure?
190 kPa
What is Emergency BC pressure?
210 kPa
When do both air compressors operate?
When pressure is below 650 kPa both operate
When pressure builds to 750-900kPa one will switch off
What pressure does the compressor Governor maintain Main Reservoir pressure at?
750-900 kPa
What happens to air compressors if compressor Governor is isolated?
If on they will stay on
If off they won’t come on
What does the Main Reservoir system supply compressed air to? (4)
Friction Braking system (aux. res)
Trip
Whistle/horn
Pneumatic auxiliary panel
What does the auxiliary reservoir do?
Supplies air to EP (friction) brakes
Air supplied via valves to BCs
What does the Main Reservoir pipe connect from/to?
Main Res air to
Auxiliary Res. (Mc Tp)
Auxiliary Pneumatic Panels (Mc)
Scharfenberg Coupler (Mc)
SPBs (Mc)
Where is the primary suspension
Vs
Secondary suspension?
Primary - between axle and bogie
Secondary - between bogie and carriage
What does the secondary suspension consist of?
Rubber mounted spring
Bump stoppers - lateral m’vmnt
Vertical dampers
Lateral dampers
What are the four braking systems in an XTrap?
Service brake
Holding brake
Emergency brake
Spring park brake
What is the service brake made up of?
ED & EP
When does EP brake operate?
At low speed when ED is ineffective
During wheel slide events
What EP equipment do Mc’s have
Vs
Equipment that Tp’s have?
Mc - 1 tread brake per wheel
1 disc per axle
Tp - 1 tread brake per wheel
What do Friction Brake Indicator lights show?
Red if friction / EP applied.
Green if friction / EP released
Which cars to ED brakes operate on?
Mc
When do ED brakes operate?
Above 10 kmh
When does brake blending occur?
5-10kmh
When does ED brake become ineffective?
5kmh
When does Holding Brake apply?
When train speed falls below 0.5kmh
EP releases - holding brake automatically applies
What is BC Holding brake pressure?
120 kPa
When does Holding Brake release?
When traction power is obtained
What is emergency brake pressure?
210 kPa
When does emergency brake apply?
When MCH is placed to emergency
Emergency stop button activated in any cab
Safety loop being de-energised (open)
Where are SPBs located?
Wheels 1, 3, 7 on Mc cars inly
How are SPBs applied?
Automatically as main res air depletes to 350 kPa
How do SPBs release?
Automatically as main res air increases
Can SPBs be applied manually?
No
Can SPBs be released manually?
Yes
Unlock and pull handle
What are the Emergency Mode Switch (EMS) Switch positions?
1 online holding brake inhibit
2 normal
3 rescued
4 rescuing
5 rescuing in propulsion
How do you charge the BP?
With EMS in 3, 4, or 5 both trains place MCH to full service brake position
When will BP pressure cause safety loop to open?
Below 300 kPa
At what BP pressure will safety loop close allowing emergency brake to release?
430 kPa
