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321 power controller.

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  #1  
Old 13th July 2018, 22:36
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pre65 pre65 is offline  
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321 power controller.

I was watching a train simulator video on You Tube of a 321 EMU between Wickford and Southminster, I line I knew well in my youth.

I noticed that the power controller was put to 4 to accelerate then moved to 0, and when speed dropped a little it was back to 4 for a few seconds.

Is that the usual way to maintain speed ?

https://www.youtube.com/watch?v=K6DkNDul0H4


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Philip.

Last edited by pre65; 13th July 2018 at 22:38.
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  #2  
Old 15th July 2018, 11:31
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Beeyar Wunby Beeyar Wunby is offline  
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Hi Phillip.

Nope, absolutely not. With old style traction (as opposed to fly by wire) you pause momentarily between notches. The motors on a 321 are on the PMOS, which is in the middle of the train, and if you fling the controller around it can make the coaches bump together - even with a 321's poor acceleration.

This is just cackhandedness. Rather than banging in and out of 4, just putting it in notch 1 (or 2 possibly) and leaving it there will maintain speed loss due to friction or incline.

'Smoothly' is what real train drivers do. Though I suspect you already know this as you asked the question.

And look. You've made me all sentimental now. I've only been away from 317/321s for a couple of years, and now inhabit the crazy world of Bum Bardier Electroluxes.

A little faster, but alot nastier....as we say.


Cheers, BW
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Old 17th July 2018, 08:31
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aussiesteve aussiesteve is offline
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G'day Philip,
I was waiting for BW to answer your question.
He being the obvious person to respond.
I did briefly take a squiz at the video clip afore the library "about to shut" bell rang.
My only exposure to Train Simulators (other than the dinkum railway unit) is the Microsoft version.
I gave up on that as it does not replicate how we drove our DC traction electric locomotives.
I did try tinkering with the engine operation code, but the latitude was not built into the original MSTS code.
Hence, the MSTS only permitted driving an electric loco as a diesel.
In smog hollow Sydney, management dictated that drivers should select each notch individually, pausing briefly.
Basically just what BW has commented.
But, many drivers would slam the controller straight into notch 3 or 4 just to get the thing moving as quickly as possible.
Doing this when climbing a grade away from a station, especially during wet weather could result in wheel slip.
Not only causing the cars to suffer "buff forces" (coupler slack run-in and out) but shudder during wheel slip.
The bane of modern day drivers be the Data Logger.
Back in the early 1990s when I was briefly playing trains in smog hollow, only one set class had a pseudo data logger.
Many of the old S sets didn't even possess a working speedo.
The common management attitude being, you can go over track speed by 5 kph to maintain the time table.
BUT, if you exceed the speed limit by 10 kph, and we find out, we will ping you.
The Data Logger today will dob you in for any violation of speed limit.
Riding with the cattle down in smog hollow now days, you can feel the continual powering and shutting off to coast.
The driver attempting to keep train speed up to the maximum, but not exceed such.
This is very evident with the modern day traction where controller notch response is very rapid.
Old cam cars (possessing resistance banks) would gradually notch out the resistance as train speed increased.
You would feel each slight surge as the notching pilot motor driven cam shaft spun.
Firstly notching out of Series resistance, thence Parallel and finally Weakfields.
But, departing up hill in wet weather, at least you could manually notch out each resistance bank to prevent wheel slip.
Manipulating the controller from notch One up to notch Two to remove a bank and back to notch One to hold.
Repeating until all Series resistance was removed and then go up to notch Three etc.
Train speed increase being directly controlled by the driver, though resulting in a very slow train speed increase.
Modern day emu controllers don't permit such manual manipulation as there are no resistance banks involved.
Notch One, starting Series, Notch Two full field Series, nothing inbetween.
Cop a wheel slip and return the controller to notch One, as you start all over again.
But, with the old cam cars, you were NOT permitted to remain in Notch One for any long period.
Doing so could burn the resistance banks.
Back in the early 1990s, inspectors would sneak in with the cattle to check how the driver was working the train.
They could tell from train performance just what the driver was doing.
Then hoof up front and burst into the cab announcing, "I've got you".
This never happened to me.
The only time that an inspector rode with me to check me out, he entered the cab to ride.
The train was running late when I jumped aboard, and I could easily have bashed it back onto table.
But, with the inspector aboard, I had to behave and do things correctly.
Hence the train continued to be late.
"Fanning" the EP brake valve was also verboten.
Rapidly moving the brake valve up and down in notch as train speed reduced approaching a platform.
Fanning the brake valve might cause the 7 step relay to jam and get out of wire sync.
Most emu trains today have blended EP and Regenerative (or dynamic) brake, on the motor cars.
But, blended braking can be a problem in wet weather.
Working an emu train in Westinghouse automatic air brake requires more concentration.
Though, modern day emu Westinghouse brake valves have graduated release which offers better train control.
Our old Metro Vickers 46 class locos were bonzer fun on a very light load train or Light Engine.
Getting going in Series, take a couple of quick resistance notches.
Then, slam the reverser into Series Parallel.
Holding the controller button in, quickly return to Notch One to engage Series Parallel and then take a couple of notches.
Slam the reverser into Parallel, and likewise, back to notch One to engage, then notch up again.
Doing this LE, the rapid acceleration could hurl you up against the cab wall, so you had to HOLD ON.
Just don't let management catch you.
Steve.
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Old 17th July 2018, 12:17
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Beeyar Wunby Beeyar Wunby is offline  
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Hi Steve

A really comprehensive answer as always.

I've never really got the hang of notching. We still have class 313s (Wikipedia link) which have a camshaft selector. You put the controller into whatever notch you want, then quickly pump the handle up to 4 and back to the notch you're on as many times as you want subnotches. I always forget to count how many times I've pumped - I think there are 7 subnotches. It gives a much finer control of power - which is a hoot as most 313s couldn't pull the skin off custard. We use notch 3 with 4 subnotches for climbing up the hill on our underground section on the Northern City Line (wiki link) If you time it right you can go all the way without touching the handle again, though I've never achieved it myself.

Also with the camshaft system you can't notch back down - ie, If you're in 4 and you want to reduce to 3, you have to shut the controller off and then go back up to 3. Real 1960's technology, but much harder work to drive. And of course they're on the inner suburban routes where you're powering up and down all the time. You can go all day on those services without seeing a green, (but I'm sure that's true of any suburban railway anywhere in the world).

An yes, 'Fanning the brake' - or 'Fannying with the brake' as my DI used to say. My first traction was BREL Networker 465s (wiki link) which are ElectroPneumatic brakes. As you know they're fed directly from the Main Res Pipe and never run out of air (normally). But my instructor's generation grew up on the 'autobrake' where you could exhaust the air quite quickly if you kept applying and releasing the brake. So when I was learning, he kept nagging me that I was fanning. After a few weeks I bet him that I could never run out of brake, and so for several days whenever I was rolling slowly I just sat there repeatedly putting the brake on and off gently. After a while he got really annoyed, and we agreed that I wouldn't irritate him, and he wouldn't nag me about fanning.

To be honest, I was using the brake too much. As you mentioned, modern trains blend (mix) the friction/air brake with the dynamic. Dynamics work brilliantly at speed, but tail off as the train slows down. At some point (~ 8mph on 465 if I remember) the dynamic drops out and the friction drops back in to bring the train to a stand. At the time, the blending algorithm was awful, and as a trainee driver it was a hard to get to grips with the fact that the braking rate suddenly and unpredictably reduced significantly just when you needed it most at the end of the platform! Many trainees, including myself, would be throwing in great lumps of brake just before the end because they hadn't anticipated the brake fade. Since then several generations of train have improved on the blending, and modern trains have very smooth & predictable brakes. Nowadays one of my little mental challenges is to see if I can do the 100 mile trip with only 1 (or possibly 2) brake handle movements at each stop (well it keeps my butterfly mind focussed).

I agree with you about MSTS. I never really took to that because you don't get the 'bum on the seat' sensation of braking that you do in the real world. But I have spent too much time on MSFS. Quite alot of train drivers harbour a secret desire to be a pilot and I'm one of them. I always thought my dream job would be a helicopter pilot, but IIUC most heli pilots here in the UK are ex-military. Anyhow I've footled around over the years building cockpits and controls for flight sims. It pandered to my electronics abilities and the online flightsim world is quite sociable. Don't think I could be real world pilot though, too clumsy.

Best wishes, BW
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Old 18th July 2018, 06:27
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G'day BW,
A chopper pilot, aye.
Just don't come flapping anywhere near my hovel.
My whole hovel shakes during the nightmare october car race event on the Mount.
Joy rider choppers thumping over me hovel in convoy every couple of minutes at VERY low altitude.
Yes, our suburban emu sets with resistance could not re-instate resistance.
You had to shut off and begin again.
But, our pair of electric locos, 85 and 86 class did permit re-instating resistance during manual notching to deter wheel slip.
Holding notch on our emu sets was Notch 1.
Whereas, holding notch on them electrics was notch 2.
To add a bank of resistance, while still in resistance, you stepped down to notch 1 and then return to notch 2.
Ya naturally can't do this once stepped out of resistance and in full field.
Them old Metro Vickers butter boxes were totally manual with relays.
You could notch back to add resistance should wheel-slip occur.
You could also Motor in Regen with them butter boxes.
On a light load train, but only in series or series-parallel, you could set them up in regen going down hill.
Then, hands free, when the train reached the bottom of the hill and commenced to climb, they would go from regen into power.
Hey Mum, Look NO hands.
Great fun.
But, you didn't do this if you were in a hurry.
On our Tangarbage emu sets, you could knock out the regen by taking notch one power while applying the brake.
SHHHSHHH! Don't tell management, you would definitely get pinged for such caper.
Doing this would keep the set in starting series power and only apply the EP brake.
But, I DID NOT TELL you this.
HA!
Yes, the regen kicks out at around 5 kph to become all EP when braking in normal method.
Them Tangarbages were also easier to manipulate in Westinghouse air brake as they have a modicum of graduated release.
But, the Chopper sets (C sets) being the first to possess thyrister chopper gate power control, were even better fun.
You could manually notch them up in series.
Steve.
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Old 20th July 2018, 06:35
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aussiesteve aussiesteve is offline
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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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