Core Traction Flashcards
(215 cards)
1
Q
How can different classes be coupled together?
A
Via a compatible coupler (all have BSI)
2
Q
What are tread brakes?
A
Where there is direct contact between the brake block and the wheel
3
Q
What are disc brakes?
A
Where a piston pushes a disc that squeezes the wheel (no direct contact with wheel itself)
4
Q
How are disc and tread brakes applied?
A
Electropneumatically- electrical signal from brake handle in cab that is converted into air
5
Q
What brakes does the 150 have and what is its max speed?
A
Tread & 75mph
6
Q
What brakes does the 155 have and what is its max speed?
A
Tread & 75mph
7
Q
What brakes does the 158 have and what is its max speed?
A
Disc & 90mph
8
Q
What brakes does the 170 have and what is its max speed?
A
Disc & 100mph
9
Q
What is the maximum coupling configuration when ECS and when in service?
A
ECS= 12 car
In service= 6 car
10
Q
Name the differences between 150/1 and 150/2?
A
1 alternator/2 alternators
Slam crew door not on TW4/ power operated local door
No vigilance/vigilance (protected by MCB)
No gangway door/gangway door
LCCB won’t get brake release if TW4 tripped/will get brake release
Egress on alternate doors/egress on all doors
Flag EBS and AWS/ rotary dial EBS and AWS
Manual sander and no WSP/ manual sander and WSP
Fuel isolation cock next to Donaldson Air filter/fuel iso cock next to isolation cock air suspension
11
Q
What is the door test procedure?
A
T key into DKS to energise Door Control Panel
Test offside first
Test crew door as local door (open, close, open) then as pax door
Check for cross feed from opposite pax door controls
Move down train and test all offside doors as pax doors
Test final crew door as pax then as local
Use door control panel to close all doors- visually check all closed then close local door
Repeat on platform side
On reaching final door, 3-2-1 on bell buzzer. Door test complete
Close door control panel and turn off DKS
12
Q
What is sole bar level?
A
Anything below the chassis
13
Q
How many bogeys per vehicle?
A
2 bogeys per vehicle
14
Q
What sits on top of bogey?
A
Bogey, chassis and then body of train
15
Q
How many parking brakes per vehicle?
A
2x per vehicle on wheels 2 and 8
16
Q
How are parking brakes applied?
A
Spring applied, air released
17
Q
How many engines per vehicle and what is the engine coupled to?
A
1 engine per vehicle which is coupled to the gearbox
18
Q
What is used to pump fluids around the engine
A
Fuel pump, oil pump, water pump
19
Q
Draw and explain the driveline
A
Refer to picture
20
Q
How is each wheel numbered on the driveline?
A
1-8 clockwise from 2nd man’s side
21
Q
What type of brakes does each wheel have?
A
Every wheel has service brakes but wheels 2 & 8 have parking brakes bolted onto them
22
Q
Which wheels have propulsion?
A
Only wheels on the driven end (3-6)
23
Q
How are the wheels on the driven end propelled?
A
By the master drive (wheels 3 & 6) and slave drive (wheels 4 & 5)
24
Q
How does the master drive receive power to pass onto the slave drive?
A
From the gearbox
25
How is each element connected on the driveline?
Via colour coded and cradled cardan shafts which slow and stop with the train and take power from one element to another
26
Which end is the train always driven from?
The free end
27
What happens to the gearbox depending on the direction of travel?
Gearbox turns depending on direction of travel
28
If the direction selector is forward in the leading vehicle, what direction is that vehicle's gearbox and what direction is the rear vehicle's gearbox?
The front vehicle's gearbox is forward and the rear vehicle's gearbox is in reverse to provide drive in the direction of travel.
29
What direction would the middle car of a 3 car train be?
Either in forward or reverse.
If the free end of the middle vehicle is closest to the driving cab, gearbox in forward as drive coming from rear wheels (correct direction)
If the free end of the middle vehicle is furthest from the driving cab, the gearbox is in reverse to propel wheels in the correct direction.
30
How does the gearbox transmit drive?
It uses oil to transmit drive and is electropneumatic from the Marton Air Box
31
How does the Marton Air Box work?
Converts electrical signal from the direction selector in the cab to air that is forced into the gearbox to select the correct output to drive the train
32
Where are TCAs located?
In a ring around the bogey to boost track circuits
33
How would you identify a free end of a vehicle?
Lifeguards, parking brakes and AWS/TPWS receivers
34
Point out each component of the BSI coupler
Look at diagram in book
35
Outline the coupling procedure
1) When approaching train, look for any non-multi stickers/not to be moved boards/bags on couplers on either vehicle
2) Safety check every cab and do static brake test in both intermediate cabs that will be coupled to determine if there are any faults before coupling
3) Consider location (unit height differences, curvatures, buffer stops, intermediate signals etc) and select most suitable unit to couple from (always couple from the 170)
4) Trains to be 6ft 6in apart then visually check both BSIs for defects or abnormalities. Check the coupler alignment
5) Ensure all external doors are closed and no people in the way
6) Draw forward to 2ft and conduct further visual check of alignment
7) Direction to fwd, 1 notch of power, release brake and when train starts rolling shut off. Allow couplings to engage and immediately apply brake step 3.
8) Direction to reverse for pull test to test mechanical coupling first. 1 notch of power and release brake. Incrementally increase power up to notch 4- if no separation, shut off and apply brake step 3.
9) Direction to neutral and then press couple for 5 seconds to electrically couple
10) To test brake continuity, direction to forward, apply brake step 2, direction back to neutral to 'trap the brake'. Observe 2.0-2.5 bar pressure in current cab and other cab.
11) Open gangway doors at this point to check other cab
12) Return to original cab, ensure tail lights switched off between vehicles on both units and reset desk & secure cab
13) Conduct static brake test in leading cab
36
Outline the uncoupling procedure
1) Consider location (curvatures, buffer stops and intermediate signals that may be impacted when reversing) and select most appropriate unit to uncouple from
2) Direction to neutral and press 'uncouple' for 5 seconds. May hear clunk
3) Direction to reverse, power notch 1 and release brake. Move back max 2ft and then apply step 3 brake
4) Illuminate external end lights on both vehicles
5) Examine both couplers
6) If unable to uncouple, couplers may be under tension- squeeze up to other unit by applying notch 2 or 3 with direction in forward and then apply step 1 and then 3 with power still on to prevent bounce back.
7) Direction to neutral, uncouple for 5 seconds and attempt to pull away again
8) Conduct static brake test in unit you have uncoupled from
37
What must you remember to do after coupling and uncoupling?
Static brake test in leading cab after coupling
Static brake test in cab you have uncoupled from after uncoupling
38
If the units split at any point or you become distracted when coupling, what must you do?
Split the unit and start again
39
How many times can you attempt to couple?
Up to 3 times but the third attempt must be from another cab
40
Is there one air system for the whole train or does each vehicle have its own air system?
Each vehicle has its own independent air system
41
Where is each independent air system fed from?
The Main Reservoir Pipe that runs from each end of the vehicle to the other
42
Where is the main reservoir pipe fed from?
The Main Air Reservoir
43
Where does the Main Air Reservoir receive air from?
The compressor
44
What pressure is the main air reservoir and main air reservoir pipe maintained at?
6.5-7.5 bar
45
If one vehicle has a faulty compressor, where can that vehicle receive air from?
Can be cross fed from other vehicles and use another vehicle's compressor
46
What action should be taken if the main reservoir pipe is leaking?
MRPIC both ends of vehicle and other vehicle's MRPIC
47
Why does MRPIC need to be used in the event of a main reservoir pipe leak?
To prevent other vehicles losing air as all systems on the air system will be deprived of air
48
How is pressure into the main air reservoir regulated?
Via an unloader valve at 6.5-7.5 bar
49
What action should be taken if the unloader valve for the main air reservoir is faulty?
Compressor Governor Isolation Cock should be used to circumvent the unloader valve and rely purely on the safety valves at 9.1 and 8.3 bar
50
How do the safety valves set at 9.1 and 8.3 bar work?
By releasing air pressures that exceed these values
51
What supplies air to the Marton Air Box?
Transmission Reservoir
52
What is located before the Transmission Reservoir to regulate the pressure and what value is this set at?
Regulating valve located before Transmission Reservoir and is set at 4.1 bar
53
What course of action should be taken if the Transmission Reservoir is leaking?
Transmission Reservoir Isolation Cock to be used
54
When using TRIC, what must you ensure that you do and why?
Keep the engine running to allow the alternator to charge batteries so that you don't lose end lighting.
55
What course of action should be taken if there is an air leak on the doors?
Use Door Reservoir Isolation Cock
56
What effect does DRIC have on the doors and what action must be taken after using this?
Removes air from the doors. All doors must be mechanically locked.
57
Where do the air bags receive air from?
The surge tanks that are fed from the Air Suspension Reservoir
58
What course of action must you take if one air bag is deflated?
All air bags on that vehicle must be deflated via the surge tanks after the Air Suspension Reservoir Isolation Cock is used.
59
What pressure is the brake reservoir maintained at?
7.0 bar
60
How is the brake reservoir protected?
By a non-return valve
61
Can the brake reservoir be isolated?
No
62
What would happen if the brake reservoir had a leak?
If the brake reservoir had a leak, there is nothing that can be done. The train is defective.
63
What is fed from the brake reservoir?
The Brake Control Unit
64
What is contained within the Brake Control Unit?
Train wires 23, 24 and 25. The 3-step relay and the variable load valve
65
What is the 3 step relay?
This applies the correct electropneumatic pressure depending on the position of the brake controller in the cab
66
What is the variable load valve?
This controls the amount of air in brake cylinders which physically applies the brakes- this can also be influenced by the passenger loading of the train giving a harsher brake application when the train is full and standing.
67
Can the brakes themselves be isolated? If so, how?
Yes via the Brake Isolation Cock
68
When would it be necessary to isolate the brakes?
In the event of dragging brakes, if the brakes were stuck on or if there was an air leak.
69
What would apply if the brakes were isolated?
Brake regulations
70
What is the Main Air Pressure Switch (MAPS)?
This applies the service brakes when the main reservoir pipe pressure is 4.5 falling and releases them when the pressure is 5.5 rising.
71
If you notice the main reservoir pipe pressure falling on the duplex gauge, what will happen?
You know that the brakes will apply soon.
72
Which in cab components are supplied by the main reservoir pipe?
Horn, sander and wiper
73
How can the horn, sander and wiper be isolated?
HIC, SIC and WIC
74
What else is supplied by the main reservoir pipe?
Emergency Coupler Isolation Cock (ECIC)
75
When would ECIC be used?
When coupling to a non-compatible unit
76
What is the default position of ECIC?
Isolated to allow the schrader hose to be inserted and then reinstated to create an air connection.
77
How can the main air reservoir be isolated?
Via the isolation cock main reservoir (ICMR)
78
What is the effect if ICMR is used?
Disables all systems after it except brake reservoir
79
What would be required if ICMR is used?
Need another vehicle's air to operate other systems
80
How does the PBAC work?
It applies the parking brake by removing air that is keeping the spring coiled (spring applied, air released)
81
When does the parking brake apply automatically?
When the main reservoir pipe drops to 1.9 bar or below
82
If both the Main Reservoir Pipe and Brake Cylinder gauges are at zero when starting, what must you do?
Monitor both rising
83
What are your actions if the Main Reservoir Pipe gauge is rising but the brake cylinder gauge isn't rising with it?
Immediately shut down train and use PBAC to stop the unit from rolling- this is because the parking brake will release when the MRP exceeds 1.9 bar but there is no air going into the brake cylinders to apply the service brakes.
84
What are your actions if the main reservoir pipe pressure exceeds 8 bar?
Report to maintenance.
85
What is the effect if there is a damaged rose valve? What must you do if this happens?
Air will drain from all systems. Must MRPIC both ends of vehicle and attached end of other vehicle.
86
How would you describe the brake in the cab?
3 step electropneumatic brake
87
If you are able to get brake release, what does this mean?
TW4 is satisfied and confirms you have brake continuity.
88
If you are unable to get brake release, what does this mean?
TW4 is not satisfied and is de-energised. You do not have brake continuity.
89
How are the brakes physically applied?
Compressed air in the brake reservoir flows into the BCU which then travels to the brake cylinders to physically apply the brake.
90
What are the normal brake cylinder pressures in each brake step?
Step 1- 1.0-1.5 bar
Step 2- 2.0-2.5 bar
Step 3- 3.0-3.5 bar
Emergency- 3.0-3.5 bar
91
How much extra brake force does the 170 have in emergency?
20%
92
Which train wires run between the brake handle in the cab and the BCU to control the pressures applies to the brakes from the cylinders?
Train wires 23, 24 and 25
93
Which train wires are energised/de-energised when brakes are released?
23 and 24 energised
94
Which train wires are energised/de-energised when brake is in step 1?
23 de-energised
95
Which train wires are energised/de-energised when brake is in step 2?
24 de-energised
96
Which train wires are energised/de-energised when brake is in step 3?
23 and 24 de-energised
97
Which train wires are energised/de-energised when brake is in emergency?
23, 24 and 25 de-energised
98
What effect does 25 being de-energised have in emergency?
Doesn't allow brake release until 3mph or below
99
How is the parking brake operated?
Spring applied, air released
100
When is the parking brake utilised?
When the air in the system depletes making the service brakes unavailable (when main reservoir pipe drops to 1.9 bar or below)
101
How can the parking brake be manually applied?
Via PBAC in the cab
102
When is the PBAC automatically applied?
When main reservoir pipe drops to 1.9 bar or below
103
In what circumstances would the MRP drop to 1.9 bar or below?
When train is stabled overnight and loses air
104
How can the parking brake be removed when the mrp is 1.9 or below?
Compressor speed up to build air
105
In what non-normal circumstances might the parking brake be used?
When propelling 'not in multiple' or when the brakes are isolated
106
When might you manually apply the PBAC at start up?
If the brake cylinder gauge doesn't rise with the main reservoir pipe pressure as the parking brake will release and there is not enough pressure in brake cylinders for service brakes to be available.
107
Do parking brakes apply to the same brake block as service brakes?
Yes
108
What pressures are shown on the duplex gauge?
The Main Reservoir Pipe and the Brake Cylinders
109
What are your actions if both pressures on duplex gauge are at zero upon starting?
Monitor both rising.
110
What are your actions if the brake cylinders don't rise with the MRP?
Parking brake will release when pressure in main reservoir pipe is 1.9 or above but if no pressure in brake cylinders, there will be no brakes and unit could roll. Immediately shut down train and apply PBAC to prevent unit from rolling.
111
What serves as the primary suspension on each bogey?
Springs and dampers
112
What is the secondary suspension on each bogey?
Air bags between chassis and body
113
What type of suspension is predominantly used?
Secondary suspension
114
What suspension can be used if the secondary suspension fails?
Primary suspension
115
How would you deal with a leak in the air suspension reservoir?
Isolate the air suspension reservoir via ASRIC to divert air around rest of system, then use surge tanks to deflate all air bags on the affected vehicle.
If pax can be moved, proceed at line speed. If pax can't be moved, proceed at 45mph
116
What must you remember if the air bags are deflated on one vehicle but not on others?
There will be a unit height difference and a harsher brake application as the train will think it is full and standing.
Must also remember any platform restrictions with deflated suspension.
117
Where does TW4 start its journey?
At the rearmost start battery and flows around all vehicles anti-clockwise
118
How many batteries are there per vehicle?
2x
119
Which side are the start batteries on?
On 2nd man's side
120
Which side are the auxiliary batteries on?
Driver's side
121
Does TW4 flow around the whole vehicle or each individual vehicle?
The whole vehicle to give brake continuity
122
What will happen if TW4 is de-energised?
Brakes will not release
123
If a TW4 problem is in your leading cab (at home), where must you deal with it?
Away- in the rear cab
124
If a TW4 problem is outside of your leading cab (away), where must you deal with it?
Home- in leading cab
125
What could brake TW4?
AWS/TPWS defective in energised cab
AWS/TPWS circuit breaker tripped in energised cab
Brake Control Circuit Breaker tripped in any vehicle
BSI couple button pressed
Compressor speed up pressed
Communication Chord (passcom)
Doors open/relesed
Door Circuit Breaker tripped with DKS on
Door switch (local) left on
DSD not depressed with direction in fwd/rev
Direction selector not in fwd/rev
EBS raised in other than leading cab
Emergency brake applied in any cab
Jumper cable defective between vehicles
MAPS below 4.5 bar
Microswitch between vehicles (155)
Shore supply (158)
Train Control Circuit Breaker (TCCB) tripped in leading cab
126
How would you overcome AWS/TPWS defective in energised cab?
Isolate AWS (also isolates TPWS)- speed restrictions apply
127
How would you overcome AWS/TPWS circuit breaker tripped in energised cab?
Reset 3x
Isolate AWS (isolates TPWS)- speed restrictions apply
128
How would you overcome BCCB tripped in any vehicle
Reset 3x
If leading cab- EBS from rear cab & WDM or assisted from front
If rear cab- EBS from front to short TW4 to leading cab only
Remember that passcoms and emergency brake in rear cab inoperative and brakes won't apply on leading vehicle in division- guard to patrol/competent person to sit in rear vehicle to contact signaller or lay protection if train divides.
129
How would you overcome BSI couple button pressed?
Press uncouple for 5 secs
130
How would you overcome compressor speed up pressed?
Switch off
131
How would you overcome passcom pulled?
Hazard light on affected vehicle
T key to reset
If cannot reset, EBS from leading cab (problem away)
If changing ends, EBS from new cab
132
How would you overcome doors open/released?
Hazard light on affected vehicle
If 1 hazard light, at least 1 door. If all hazard lights, door release given.
Ask guard to close doors.
133
How would you overcome DSD not depressed with direction in fwd/rev?
Put foot on DSD
If defective, change ends and WDM as DSD not on TW4 in the rear so can't EBS- when key in at other end, DSD will work as fault remains in other cab.
134
How would you overcome direction selector not in fwd/rev?
Place direction to fwd/rev
135
How would you overcome DCCB tripped with DKS on?
Reset CB 3x
Faulty DKS always problem as DCCB protects system
EBS from leading cab as problem away and TIS
136
How would you overcome door local switch left on?
Switch off
137
How would you overcome EBS raised in other than leading cab?
EBS from new cab- if fault in new cab, cannot EBS and must be assisted from front.
138
How would you overcome emergency brake applied in any cab?
Move brake away from emergency
139
How would you overcome jumper cable defective between vehicles?
Maintenance to resolve
140
How would you overcome MAPS below 4.5 bar?
Compressor speed up - if this doesn't work, identify leak and MRPIC then EBS to build pressure
141
How would you overcome microswitch between vehicles (155)?
Maintenance to resolve
142
How would you overcome shore supply (158)?
Maintenance to resolve
143
How would you overcome TCCB tripping in leading cab?
Dead desk- brakes won't release as part of desk
Reset CB up to 3x
EBS from other cab but may need to TIS as could give power fault
144
What could give you a hazard light?
Open/released doors
Passcom
Brake Control Circuit Breaker
Fire system activated
TCA fault
145
Which reasons for a hazard light would also give you a brake demand?
Passcom
Brake Circuit Breaker
Doors open/released
146
If you receive a brake demand, what must always be your first action?
Check TPWS panel
147
What is the Emergency Bypass Switch (EBS)?
Used to short TW4 to circumvent a brake fault
148
Can EBS be used for power faults?
No
149
How do you operate flag type EBS?
Insert key and pull flag as far as possible. Hatching visible outside and text with instructions visible inside
150
How do you operate EBS rotary dial type?
Key in and rotate on circular dial. Blue light illuminates when operated.
151
Can EBS be operated from a cab with a problem?
No, you must go away if problem is at home. EBS from rear cab.
152
If EBS is raised, what must you be aware of?
Nothing outside of the cab will work- passcoms and emergency brake in rear cab will be inoperative. Guard to patrol for issues.
If the train divides with EBS operated, there will be no brake demand in the front vehicle. Competent person must sit in rear vehicle to inform signaller or lay emergency protection in event of division.
153
What can prevent power from being taken?
DRA on, brake steps higher than 1, applying brake with power applied and not returning to notch 0 first, direction not in fwd/rev, doors being open.
154
What usually holds the doors shut?
Air
155
When the doors are closed, how does the power safety loop work?
When the doors are closed, magnets in the door complete the power safety loop (auto door checker)- if this circuit is not made, no power as the train thinks the doors are open
156
What are your actions if the doors are closed but there is an issue with the magnet causing the train to think its doors are open?
Bypass the power safety loop via Traction Interlock Switch (TIS)
157
If TIS is used, what does this mean?
There is no 'auto door checker' so guard and driver must manually check doors are closed on both sides
158
At what point must you check manually that doors are closed on both sides?
Before operating TIS.
159
When can you operate TIS?
With permission from duty control manager
When at a stand
After doors have been manually checked to confirm they are closed
Then inform signaller when operated. Do not move until instructed
Agree safe method of dispatch with guard as bell buzzer lost
160
What must the guard subsequently do at each station stop?
Check that the doors open and close after each station stop
161
When TIS is operated, what must you be aware of and what must you do as a result?
Bell buzzer will be lost. Agree safe method of dispatch with guard.
162
What are your actions at the end of the journey after operating TIS?
Reinstate TIS, complete repair book and put broken seal on book.
163
What are all electrical systems protected by?
Miniature Circuit Breakers
164
What type of MCBs are there?
Essential/non-essential
165
Where are non-essential MCBs located?
Bottom bank
166
Where are essential MCBs located?
Top bank
167
What feeds essential MCBs?
Starter batteries
168
What feeds non-essential MCBs?
Auxiliary batteries
169
How can another vehicle's MCBs be fed if there is an issue with the battery on one vehicle?
Each battery can cross feed other vehicle's- may need to use cross feed function
170
How many times can MCBs be reset on driver's authority?
3x except Earth MCB which can only be reset 1x
171
Which MCBs tripping will result in a brake demand if tripped in leading cab due to breaking TW4?
BATD
BCCB
AWS/TPWS
TCCB
DCCB
172
Which MCBs tripping will result in a brake demand if tripped in the rear cab due to breaking TW4?
BD
BCCB
DCCB
173
What are your actions in relation to MCBs if you lose an engine?
Trip non-essential MCBs to save battery - leave clipboard light on as when this goes out you know you have lost end lighting
174
What is the initial brake application on tread brake trains in normal and low adhesion? Why is this?
Step 1 in normal and low adhesion. This is the first brake step that WSP will activate if fitted
175
What is the initial brake application on disc brake trains in normal and low adhesion? Why is this?
Step 2 in normal and low adhesion. This is the first brake step that WSP will activate if fitted.
176
What does LCCB protect?
The local control panel on outside of train
177
What is the effect of LCCB tripping in front cab?
Local engine shuts down, all others revert to idle. Starter motor and fire protection for that engine inoperative, speedo to zero, no engine stop light and end lighting lost (gearbox train, unit and local lit for 30 secs)
178
If the gearbox train, unit and local lit for longer than 30 secs, what should you consider?
TCA fault
179
What is the effect of LCCB tripping in rear cab?
That engine shuts down but others unaffected
180
Do you get a brake demand if LCCB trips?
No as TW4 is not affected
181
When might you get a brake demand if LCCB is tripped? What might you need to do to overcome this?
On 150/1- may need to EBS to overcome
182
What is the correct course of action whenever LCCB trips?
Reset 3x, try to restart engine from outside and ESIS to isolate affected engine if cannot restart engine.
183
What should you do if you lose end lighting as a result of LCCB tripping?
Follow DOTE instructions for headlight loss.
184
What does TCCB protect in leading cab? What happens if tripped?
Desk- if tripped, dead desk & brake demand as brakes are part of desk.
185
What are your actions if TCCB trips in leading cab?
Reset 3x. If unsuccessful, EBS from rear cab and make WDM/assistance from front but must TIS in both circumstances to regain power.
186
What does TCCB protect in rear cab? What happens if tripped?
Protects power safety loop. If tripped, power fault as this protects auto door checker. Total loss of power and all engines idle
187
What are your actions if TCCB trips in rear cab?
TIS to regain power
188
Do you need to manually lock doors when TIS operated?
No, only need to manually lock if DRIC used to isolate air to doors
189
What forms need to be completed when TIS used?
A & B form, maintenance log, broken TIS seal on log and reinstate TIS at end of journey so next driver investigates.
190
How can you tell how much fuel is left in the fuel system?
Via sight glass
191
Draw and explain the fuel system
Refer to diagram
Fuel sits in the fuel tank and can be isolated via the fuel tank isolation cock
Auxiliary heater sits by fuel tank to warm the fuel in cold conditions- can be isolated via auxiliary heater isolation cock
Fuel filtered to remove impurities before pumped around system via fuel pump
Fuel passes through fuel pump governor which regulates flow of fuel depending on whether engine is idle or not (decides how much fuel is needed)
Further fuel regulation happens at multi-throttle control unit depending on how much power is requested in cab
Fuel passes through ERS (engine shut down valve)- when energised, fuel can flow to the engine but when de-energised, it will shut the engine down to protect itself.
If ERS satisfied, fuel flows to the engine via the injectors to fire the engine
192
What is the engine run solenoid?
Engine shut down valve- self preservation is the purpose
193
What happens if the ERS is de-energised?
The electrical valve closes and engine shuts down to protect itself
194
What happens if the ERS is energised?
If satisfied, fuel can flow to the engine via injectors
195
What causes ERS to de-energise?
Fire system operated
Fire CB tripped
Fire test button operated
Fire integrity lost
Loss of electrical supply (fault, not battery isolation)
Low water/coolant via Mowbray float
Low lubricating oil pressure
Local Control Circuit Breaker tripped
Engine stop button pressed internally or externally
Driver's key removed for more than 15 mins
196
Where are the engine stop buttons located?
One in each cab and 2x located at sole bar
197
What will happen if ERS is faulty?
The engines will not shut down- fuel isolation cock to be operated to exhaust system of fuel
198
Draw and explain the coolant system
Low water levels in header tank are detected by Mowbray Float causing the engine to shut down via ERS to protect itself as engine can't run without coolant
Circulating coolant removes excess heat from the system and is pumped through engine and around the system via the water pump
If the thermostat detects a significant rise in coolant temperature, the coolant is redirected to the fan behind the radiator to cool it before it re-enters the system. If the thermostat deems the coolant is an acceptable temperature, it is not diverted via the fan and can circumvent this step.
The fan is powered by hydrostatic oil which is cooling
The hotter the coolant, the faster the fan spins (dictated by fan speed control unit
199
Draw and explain the lubrication system
Lubrication system protects moving parts from wear and cools the engine
Engine lubricant used to cool and lubricate
Lubricant starts in sump where oil is stored and is pumped via oil pump around the system
Oil passes a high pressure valve set at 140psi
Oil passes a regulator valve (idle 10psi, max 45psi, ERS 8psi). If the lubricating oil pressure drops to 8psi, ERS shuts down the engine
Oil then passes the thermostat which decides if oil needs to pass through a cooler if too hot or is cool enough to travel via the cool route. Both channels then feed into a filter to remove impurities before passing into the engine
Excess oil then returns to the sump
200
Draw and explain the fire system
There is 1 fire system per vehicle- only for engine fires
If the primary system (auto bottle) doesn't activate at 3mph or below, can be manually overridden in cab. If fire still not extinguished, secondary system activated by pull handle at sole bar.
Fire Control Unit is brain of system (5 components- having all gives integrity):
- Manual override of fire bottle
- Fire Isolation Switch
- Fire Test Button
- Fire MCB
- Fire Integrity Light
If fire detected:
- Fire bells
- Hazard light on affected vehicle- no brake demand
- Shut down of local engine via ERS
- Engine stop light illuminates
- Auto fire bottle deploys at 3mph or less
Pyrolytic wire surrounds engine and auxiliary heater- if unusual rise in temperature, fire control unit activated and gives 5 indications.
2 fire bottles per vehicle- manual and auto (both at sole bar)
201
What 5 components give you fire integrity via Fire Control Unit?
- Manual Override of fire bottle
- Fire Isolation Switch
- Fire Test button
- Fire integrity light
- Fire MCB
202
What 5 indications will you get of a fire?
- Fire bells
- Hazard light on affected vehicle- no brake demand
- Auto bottle deploys 3mph or below
- Local Engine shuts down via ERS
- Engine stop light illuminates
203
What must you check during SCU to check if you have fire integrity?
Fire integrity light
204
What are your actions if fire integrity light is not illuminated?
Press the button- if it then illuminates, bulb is working fine but you have no integrity.
If it doesn't illuminate but engine is on, bulb is flat- engine wouldn't start without integrity
205
What happens when you press the fire test button?
Shuts down local engine, illuminates hazard light and sounds fire bells
206
What is the fire system protected by?
MCB
207
What is the effect if the fire MCB trips?
System defective and local engine shuts down- if cannot be reset, system must be isolated.
208
What faults could cause the engine not to turn?
Electrical fault:
- Direction not in neutral
- ESIS isolated
- Starter battery flat/isolated
- TCCB tripped
- Fire integrity lost
- Fire system has self identified a fault
- Fire bottles previously discharged
- Fire Control CB tripped
- LCCB tripped
209
What faults could cause the engine to turn but not fire?
Wet fault:
- Low coolant via mowbray float
- Low or high lubricating oil pressure
- No fuel or fuel isolation cock isolated
210
What faults could cause an engine to revert to idle?
- Low hydrostatic oil causes engine to overheat
- Low coolant causes engine to overheat
- Lubricating oil overheats
- LCCB tripped
- Gearbox fault
211
What faults could cause an engine to shut down in service?
- Local Control CB tripped
- Low water
- Low oil
- Fuel starvation
- Fire MCB tripped
- Fire detected
- Fire integrity lost
212
What faults could cause no power?
- Throttle not initially at zero
- Brake not in step 1
- Direction not in fwd/rev
- DRA on
- Door open/fault
- Engine not running
- Gearbox fault
213
What could cause a gearbox fault light?
- Wheel slip/slide
- Speed probe issue
- Gearbox in neutral/not fully rotated when changing ends
- TCA fault/TCA MCB tripped
214
What could cause no lighting?
- Emergency lighting MCB tripped
- Low battery
- LCCB tripped (engine off so alternator can't charge batteries- loss of end lighting)
215
Why might AWS/TPWS not self test?
- AWS/TPWS isolated
- AWS/TPWS MCB tripped
