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Go Back   Railway Forum > Diesel & Electric > Diesel & Electric Discussion

Tube 1938 stock

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Old 2nd March 2018, 03:29
aussiesteve's Avatar
aussiesteve aussiesteve is offline
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Tube 1938 stock

Having perused the DoE Moorgate 1975 incident report.
This has provided some insight into the operation of Tube 1938 stock.
I have noticed some similarities with our Sydney emu operation.
I have had to ask some questions to my ETR (electric train roster) buddy in regard to single decker red rattler facets.
I have had a go at them, but such being a very long time ago, I forget the specifics.
So, I may need to adjust slightly this posting when he responds.
The Tube 1938 stock 9 banks of resistance does conform to our NSWR 85 and 86 class electric locomotives.
Worked by pilot motor driven notching cam shafts.
However the butter boxes, NSWR 46 class Metrovick things, had 19 manual notches of resistance, via relays.
I have driven Cityrail single deckers and double deckers with resistance, plus also those with high speed chopper gates.
I forget the number of banks of resistance, which would be at least 6 and possibly 9.
Four throttle notches being available.
Notch 1, starting series full resistance; notch 2, full field series; notch 3 parallel; notch 4 weakfields.
As mentioned in other threads, the NSWR overhead system being prehistoric 1500 VDC.
You could notch up manually within resistance in wet weather on a grade.
Notch 1 holding and notch 2 step up.
Enter notch one and then up to notch 2 to remove a bank of resistance, and then back to notch 1 to hold.
Repeating this until out of resistance.
I am not sure if this was performed on Tube 1938 stock, but would assume that such would be possible.
With the NSWR 85 and 86 class, manual notching was similar, but notch 2 being holding with notch 3 for step up.
Notch one would be used as step down to reinstate a bank of resistance if wheel slip occurred.
Notch 4 being full field; zone between 4 and 5 being weakfields, notch 5 transition to next motor combination.
On a smog hollow squirt emu, you had to shut off power and recommence to notch up manually if necessary.
Once stepped out of series resistance, you could then go for parallel, and evetually weakfields.
On electric locomotives, ours being Co-Co wheel arrangement, three motor combinations were available.
Series, Series-Parallel and Parallel.
But, with smog hollow squirts being two axle bogies, only series and parallel motor combinations are available.
Prior to the introduction of the Tangarbage (Tangara) emu, the deadman throttle was via depressing the master controller.
As with the Tube 1938 stock, the master controller can be returned towards the driver once notched up to parallel or weakies.
This to allow a more comfortable position of the master controller to depress to control the deadman.
But, if the No Volt Relay tripped, the cam shafts for that motor car would resume to where ever the throttle was positioned.
It was verboten to motor with the master controller in notch one as a NVR trip would return that car to full resistance series.
No cooling fans exist on smog hollow emu sets with resistance.
Hence, if remaining in full resistance series, the resistance banks could melt.
However, with emu sets possessing high speed chopper gates for power control, there are no resistance banks to melt.
I am intrigued by the then Tube mandate to stop at the penultimate station in Westinghouse, not EP.
This naturally being to ensure that Westinghouse is operational for use if the EP fails.
However, a difference being with the brake valve.
Here with the standard 7 step Westcode brake valve, Westinghouse is underneath EP, and not at a further sweep of the valve handle.
Should EP fail here, movement of the brake valve within the 7 step EP application zone will cause Westinghouse application.
To prevent a locked up volume potentially occurring with any air leak, each initial EP application also causes a minimum reduction Westinghouse application.
When the EP is then fully released, the Westinghouse automatic brake minimum reduction is then also released.
Should this not occur and an air leak exist causing the car tripple valves to function, the air sent to the brake cylinders would not be released.
Here, it is not mandated that Westinghouse should be operated during normal working.
However, when approaching a terminal station, train speed must be such that Westinghouse would stop the train.
Blended EP and regenerative (dynamic) brake is provided on motor cars with chopper gate power control.
Trailer cars having EP.
The regen will function down to approximately 5 kph and then switch out to become only EP.
I would also consider that employing Westinghouse at the very same station en route on a yo yo would not provide proficiency.
All stations have a subtle difference in grade, and curvature.
I would also surmise that performing repetitive yo yo services would become very BORING for the train crew.
Variety provides interest and prevents boredom.
I did not think much of management desires to sectorize the smog hollow squirt network.
Crews working only specific sectors and not over the entire network.
Variety is the spice of life.
Different traction types and different routes keep the operator alert.
Plus, a total system qualification provides for relief substitution and emergency working.
With crews sectorized, if one sector suddenly lacks qualified crews it becomes unworkable.
Prior to the sword of Damocles (privatization) falling, Lithgow freight crews were qualified for 895 kms of route knowledge.
Once accustomed to the regular method, you could then experiment with variations of working.
Find out where you could coast, and where you could not coast.
Cop a challenge when hurled into a road not normally traversed.
I did get a startle one night when working down the Illawarra to Inner Harbour not long after becoming qualified.
A fair chunk of the double track Illawarra being Bi-Directional signalling.
The ten tunnels climbing the 1 in 90 from Zig Zag to Edgecombe had been one of the first sections converted to Bi-Di.
However, it was mandated that for Bi-Di to be utilized the Coalstage signalman must advise train crews of such.
But, I quickly discovered that down on the Illawarra, it was common place to utilize Bi-Di unannounced.
The Bi-Di switched in to run a pas around a freighter.
Having squizzed a Green in an adjacent signal in the Down direction on the UP Main, I was pondering.
Suddenly, Down interurban flew past.
I almost fell out of me seat.
My brain then functioned and I deduced that I would shortly run into a Yellow.
Sure enough, a Yellow glowed at me around the curve and I had to hurl out the anchors.
I would encounter a Red signal ahead where the interurban had gone back across in front of me.
My offsider had also been aroused by the hurtling interurban.
WHAT was that, he begged, the urban having rattled past his partly open cab window ?
An urban going around us, I replied.
Crikey, can they do that down here, he stammered.
Another time, likewise working a coalie to Inner harbour, I was kept rolling along the UP Main from Hurstville.
There actually being FOUR subsequent turnouts to cross to the Down Main.
When I passed the third turnout, my offsider became very anxious.
It was rare indeed to proceed all the way towards Oatley before turning out back to the Down Main.
No doubt that Hurstville box wanted us to do a rail clean on the rarely used points.
You're in trouble now, me offsider started yelling.
WHY ?, I responded.
He had obviously not been all the way before to Oatley.
We'll get suspended for this, he squeaked.
Wait and see, I replied.
When he finally squizzed the top yellow in signal SM 1057 UI, he finally calmed down.
HOW did you know about that, he demanded ?
ROAD Knowledge, I returned.

Last edited by aussiesteve; 2nd March 2018 at 03:30. Reason: typos
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