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Old 20th July 2018, 06:35
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aussiesteve aussiesteve is offline
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Join Date: Dec 2017
Location: Bathurst
Posts: 577
G'day Philip and BW,
I have been scrounging on the www and unearthed some UK emu operation info.
One document concerning the Westcode 3 step brake valve.
Only a very basic details document from Eversholt concerning the Class 321.
AP Waggonz simulator instructions for the operation of the Class 313.
And, the Northern Class 323 driver training manual.
Firstly, the Westcode 3 step brake valve is not similar to that utilized here on our pre-AC traction emu sets.
Here, we utilize the Westcode 7 step brake valve.
So, this is probably why "fanning" the EP brake valve here is more of a drama, due to possibly the relay valve jamming.
No, you won't necessarily run out of air with EP (electro-pneumatic).
But, it is in regard to creating a locked up volume and sticking brakes.
Westinghouse with only full release (not graduated release), YES, you can run out of air.
The old rule of thumb being, any more than three quick consecutive applications and release, and you have NO air left.
That air, being in the wagon auxiliary reservoirs to enter the brake cylinders to apply the brakes.
Auxiliary air pressure supplied via the triple valve from the brake pipe when the brake valve is in the release-running position.
With the Westcode 7 step brake valve, the initial EP application also causes a Minimum reduction of Westinghouse.
This to operate the wagon triple valves and send air from the wagon auxiliaries to the brake cylinders.
No train is completely air tight, and any air leakage can create a locked-up volume and potentially sticking brakes.
When the EP brake valve is finally returned to release-running, the Westinghouse auto brake is likewise released.
Should this not occur, and if an air leak does exist, this can inadvertently activate the wagon triple valves.
Air entering the brake cylinders (as separate from EP brake operation) to remain in there and cause dragging brakes.
I have not driven any of our recent AC traction (DC overhead supply) emu sets, so am not aware of the cab layout.
All of the emu sets here that I have driven possess separate controls for the master controller and for the brake valve.
It is interesting that with your Class 323, the combined controller has a "hill start button" to maintain brakes while commencing to power.
Naturally, moving the controller from brake through the gate and into power range would release the train brakes.
The train then rolling backwards on a climbing grade before traction power can propel it forward.
I am reminded of my exposure to "the railway" simulator in smog hollow back in 1993.
The comment by BW about the lack of bum on the seat sensation with the MSTS also being a facet of the Sydney thing.
Track video had been recorded during the middle of the day, hence high contrast with almost nil distinguishment of signal indications.
Acceleration was just like the opening to Star Wars, merged with Star Trek; "WARP speed Mr Zulu".
The recorded video stationary display eventually blurring to catch up with train speed.
I discovered that you could slam through 25 kph turnouts in excess of 115 kph and NOT derail.
You could release the train brake on a falling 1 in 40 grade while stationary and the simulated train would not roll no where.
When management begged my comments, I just made one.
Go and grab four burly blokes and two lengths of 4 x 2 (lumber).
Jam the lumber under the seat and get them blokes to bounce you up and down and sideways.
Management were not impressed with me comment.
I believe that vast improvements have been made to the "railway" simulator since.
The Class 313 emu set with resistance banks and four power notches is very familiar to me.
The power operation of such being identical to the cam cars in service here.
Though, the info indicates a total of 8 banks of resistance on the Class 313.
From memory, though I could be wrong, there are only 6 banks of resistance on our old cam cars.
One facet of our double decker emu sets that will affect braking is the load compensator attached to the air bag suspension.
As cattle load increases and decreases at stations, the air pressure is altered in the air bag suspension.
This will also occur as the train brakes to halt at a station.
The sudden nose dive will cause the air bag suspension adjustment to occur.
This suddenly alters the weight of the cars and consequent braking characteristic.
As the train slows down and resettles to horizontal, the air bag suspension re-adjusting and releasing air pressure.
This will affect the braking characteristic, especially for a rapid deceleration.
Hence, blokes will apply increased brake force, if not already in maximum, and then the train will stop short.
Thusly, the fanning of the EP brake valve to attempt to avert this.
This affect will also occur when in Westinghouse air brake and is far more difficult to rectify.
I remember one day being comfortable reading reports when a driver begged me to do a Quay Circle for him.
I had not noticed the arrival of the train, which was stopped a goodly two car lengths up the platform.
Many drivers requested the Quay Circle shortcut to permit going to the dunny, or for tucker, or go home early.
It took 14 minutes run time to navigate around the city circle underground and back to Central.
I agreed and while hoofing out along the platform begged, You got only 6 cars on ?
He responded, NO, it has 8 cars.
E GADs, LOOK where you stopped, I commented, you would have two swinging off the end of the platform.
EP is a failure, HE blurted, it is in Westinghouse; and sprinted away before I could glean any more into.
Sure enough, the log book indicated a plethora of comments re the EP being a total failure.
With them old S sets, you had to come in hard and make a decent Westinghouse application to stop.
This attempting to avert the air bag suspension effect.
I worked it around the underground and was met by the outgoing driver back at Central.
As he jumped in, I commented; EP is a failure and it is in Westinghouse.
I don't care, he stressed, I am getting a short cut and working home early.
The S set blasted off into the boonies of the Metrop.
I returned to reading reports.
The next day was an identical scenario.
Perched on platforms 20/21 (out of management sight and mind), yet again, I was interrupted for a Quay Circle.
An S set was parked a goodly couple of cars up the platform.
As I approached, E GADs, the same stinking 8 car set, again swinging two cars off the end of the platform.
Around on 22 after the circle, I commented to the outgoing driver the same situation.
WHAT, he stammered, I ain't never worked one in Westinghouse afore.
Well, you is about to do that today, Bon Voyage.
Not being my train, I could not make an official complaint.
But, I did phone the Quippies (fix it blokes) to beg what was the game plan for that particular set.
Going OK ain't it, was all he commented and hung up.
A few days later, I was back down in smog hollow.
But, this time I had been assigned a runner.
My expression must have said it all when this same stinking 8 car set lobbed in halted a couple of cars up the platform.
The train was a goodly 10 minutes late.
A bedraggled driver emerged, sweating profusely, stammering that EP was a failure and he had all manner of problem.
HMMM.
I had to work the thing out to Snake Gully (East Hills and return).
I did the wrong thing.
I belted the thing to make landing in Westinghouse easier.
When I lobbed into Snake Gully, the thing was back on table.
I was also a lather of sweat.
I phoned the Quippies stating that the thing was horrendous.
Can't be anything wrong with it, you are back on table, he mused and hung up.
HMMMM.
So, returning to the city, I bludged and made the thing a goodly 15 minutes late.
Waiting on the platform at Central were the quippies.
It's a total failure, I commented as I strode away.
OK, they agreed and it was worked out of traffic empty to the car sheds.
After some weeks of anguish for blokes, I finally got rid of the thing.
It's all a game, don't ya know.
Steve.
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