Motor transition

[Tamer]

From what I understand, diesel electric locomotives (and all electrically driven locomotives in general) transition their motors between series and parallel as they pick up speed to avoid damage. First and early second generation diesels (F3s and GP9s) required the operator to transition the motors manually while more modern locomotives (such as the SD40 IRL or the DE6 in game) perform transition automatically.

My question is: now that mod support for trains has been confirmed, will we have the option to equip locomotives with manual transition to simulate older designs?

[boris.glevrk]

First we need to have automatic transition introduced...

[IZHN3000]

Is your explaining about rheostatic control?
If so, I would like to better understanding about your suggestion.
I am ashamed but I don't know much about method of operation of F3s and GP9s...

For electric locomotives, I know that Japanese National Railways "EF64" has 14 notches on its power control lever.
The detail is ;
･Neutral notch (Use while stopping or coasting.)
･6 weaker-current series notches (Use when starting or very slow speed running.)
･Series notch (Use when slow speed running.)
･Series-parallel notch (Use between slow speed and rated speed running.)
･Parallel notch (Use when rated speed or nearly.)
･4 (parallel) weak field control notches (Use between rated speed and maximum speed running.)

The driver uses these notches properly while checking the ammeter and the notch-up forbidden indicate lamp to prevent overcurrent.
If an overcurrent occurs, the circuit breaker immediately shut down the circuit safely.

If your idea is close to above, I think that is an important system.
And I think that loco needs larger and easier-to-read ammeter and voltmeter. (If possible, the notch-up forbidden indicate lamp, too.)

[Exia Lennelluc]

i know some sd 70 after notch 4 it will transition

[Tamer]

IZHN3000, you have the idea as to what I am talking about, and the method you described is just one way of handling manual motor transition. EMD locomotives like the F3 and the GP9 had a transition lever separate from the 8 notch throttle. That transition lever also contains an extra position to turn the throttle into a dynamic brake lever (if the loco is equipped). Like in the Japanese EF64 you talked about, operators in a EMD locomotive would be following an ammeter with markings on it telling them when to transition the motors. I believe that ammeter is called the transition meter.

[IZHN3000]

Originally posted by Tamer:

IZHN3000, you have the idea as to what I am talking about, and the method you described is just one way of handling manual motor transition. EMD locomotives like the F3 and the GP9 had a transition lever separate from the 8 notch throttle. That transition lever also contains an extra position to turn the throttle into a dynamic brake lever (if the loco is equipped). Like in the Japanese EF64 you talked about, operators in a EMD locomotive would be following an ammeter with markings on it telling them when to transition the motors. I believe that ammeter is called the transition meter.

Thank you very much for your description!
I am convinced that your idea will make the game more interesting.
I don't know what generation of loco the DE6 is, so I hope developers to consider it.

And, for electric loco that are planned to be implemented in the future, I strongly hope that series-parallel manual transition system (= rheostatic control) will be implemented.

[marcospaiva7]

Eu não consigo entra no trem alguém com o mesmo problema

[Altfuture]

Could you please link to a video or a similar source, to see how this works at a glance? We will consider it, but no promises. Thanks!

[Tamer]

In the US this system was phased out in the 1950s and 60s with many existing locos retrofitted, so videos depicting this system in action are rare to non-existent as it has been long replaced by automatic transition. I did find an operator's manual for the EMD F3 locomotive and a video of a man showing off the cab of a functional F3. Links to both are below.

PDF manual for an F3 locomotive. Section 2 details the system for an operator.
https://www.alternatewars.com/BBOW/Railroads/EMD_F3_DLW_OM.pdf

Video inside a functional F3. The guy talks about the transition lever at around 2 minute mark

I'll keep looking and will post more if i find something else. If anybody else spots useful resources, please share them.
The TL/DR on the operational principal for Derail Valley's purposes is: the amperage in the motors starts high and voltage is relatively low. As speed increases, amperage decreases and voltage increases from building resistance. How motors are connected to the generator is changed by means of transition circuits to decrease resistance at higher speeds and avoid damage from generator over-voltage. Change in motor connection, say from series to parallel, results in a decrease in resistance allowing motors to run faster.

Edit: fixed links

[IZHN3000]

This is a description of the electric loco.

Unfortunately, I can not find the video because the rule has forbidden ordinary people to enter the driver's cab during operation in Japan.
I can not help it, so I link the photos.
An example of EF64 is shown here, so please read it together with comment number #2.

This is a photo of the power control lever. [detail.chiebukuro.yahoo.co.jp]
(Click on the photo to enlarge it.)
Blue letters indicate the power notch, and red letters indicate the dynamic brake notches.
There are 14 notches. (The neutral notch (in Japanese "切") is not shown in the photo, but it is above the "1".)

Detail of power notch (= blue letters) ;
"1" to "6" is weaker-current series notches.
"S" is series notch.
"SP" is series-parallel notch.
"P" is Parallel notch.
"F1" to "F4" is (parallel) weak field control notches.

Dynamic brake notches (= red letters) are indicated by "B1" to "B13", and the larger the number, the stronger the braking force.
Use another lever to switch to dynamic braking mode, and then use this control lever to adjust the braking force.
(Unlike some diesel-electric loco, there is no switch-waiting time.)

This is instrument panel [ameblo.jp]
The large meters lined up side by side are described in order from the right.
･Ammeter for control circuit.
･Ammeter for electric motor of multiple unit.
･Main ammeter for electric motor.
･Speedometer.
･Pressure gauge for air brake reservoir.
･Pressure gauge for brake pipe of the train brakes.

This is notch-up forbidden indicate lamp. [ameblo.jp]
Although it is written as "進**" in Japanese, it is actually "進段".
It is just below main ammeter for electric motor.

The TL/DR on the operational principal for Derail Valley's purposes is almost the same as the explanation of Tamer.

Originally posted by Tamer:

The TL/DR on the operational principal for Derail Valley's purposes is: the amperage in the motors starts high and voltage is relatively low. As speed increases, amperage decreases and voltage increases from building resistance. How motors are connected to the generator is changed by means of transition circuits to decrease resistance at higher speeds and avoid damage from generator over-voltage. Change in motor connection, say from series to parallel, results in a decrease in resistance allowing motors to run faster.

And, notch-up forbidden indicate lamp is linked with main ammeter for electric motor, and the lamp turns off when the current value reaches a safe level.

[TB in 3D]

I think that development of automatic transition by EMD in the USA occurred during the production of the F3, like 1947-49. Manual transition levers existed on locomotives like the GP9 (1954-58) in order to control older locomotives trailing in the MU consist. The manual transition controls were included on EMDs through the early 1970s, where the Dash-2 line eliminated the controls from the engineers control stand.

Old EMDs (think F3-F7-GP9) had four steps of transition: series-parallel, series-parallel shunt, full parallel, full parallel shunt. With manual transition, I think you had to throttle down to idle and move the transition lever for each stage of transition before throttling back up. With automatic transition, you really only notice the change from the 2nd stage to the 3rd stage, which would change from series-parallel to full parallel. You could leave the throttle alone, and the locomotive would automatically throttle down, make transition, and throttle back up again.

The GP9s I worked with all had automatic transition. It seems like it happened around 22-25 mph for locomotives with a 65 mph maximum speed. One of them didn't like making the change, and it would automatically throttle down to make transition, fail, and then throttle back up to catch up after the failure. When running about 25 mph, this locomotive would endlessly repeat the process. You could see dark exhaust coming from the stacks about every 10 seconds as it would briefly throttle up. This was in an MU consist of four GP9s.

I think transition is based on a speed/maximum speed ratio on the older EMDs. They used to be big paddle-contacts inside the electrical cabinet that would change position at transition. You are essentially re-wiring the electrical system of the locomotive very quickly. I seem to recall the process taking 5-10 seconds depending on which locomotive you used; every locomotive has a "personality".

Newer direct-current locomotives made transition in different ways that I'm not personally experienced with. I think by the early 1980s, EMDs were making transition inside the Main Generator/Alternator without the use of the paddle-contacts. AC-powered locomotives don't need transition and use a different system to regulate power to the motors.

I know this is an anecdotal response, but I think it helps to hear practical examples to pair with the technical documents.

[IZHN3000]

Originally posted by sunnhead60:

Newer direct-current locomotives made transition in different ways that I'm not personally experienced with. I think by the early 1980s, EMDs were making transition inside the Main Generator/Alternator without the use of the paddle-contacts. AC-powered locomotives don't need transition and use a different system to regulate power to the motors.

After reading your comment, I noticed a lack of explanation.
My explanation of EF64 was about DC electric loco.
And, I noticed that the Serbian Railways, which seems to be the model of the game, are mainly AC power.
I didn't consider the difference in electric power between diesel-electric locos and electric locos at all.
I am ashamed of my lack of consideration.

As you pointed out, AC locos don't need transition.
There is an example where control is performed using magnetic amplifier, thyristor, etc. instead of rheostatic control.

As another explanation, I will explain about the Japanese AC electric loco "ED75".
The control system is magnetic amplifier, automatic mechanical switch, and transformer in combination.

This is a video of the power control lever.
https://www.youtube.com/watch?v=1g25u8dep-g
There are 35 notches in total, including the neutral notch (in Japanese "切").
Note : ED75 is not equipped with dynamic brake.

This is instrument panel.[north-polis.travel.coocan.jp]
The large meters lined up side by side are explained in order from the right.
･Main circuit voltmeter
･Ammeter for No.4 electric motor.
･Ammeter for No.1 electric motor.
･Speedometer.
･Pressure gauge for air brake reservoir.
･Pressure gauge for brake pipe of the train brakes.

I can't find an easy-to-look photo, but the notch-up forbidden indicate lamp is below the speedometer.
It is almost same system as EF64, the notch-up forbidden indicate lamp is linked with ammeter for electric motor, and the lamp turns off when the current value reaches a safe level.
The driver uses these notches properly while checking the ammeter and the notch-up forbidden indicate lamp to prevent overcurrent.
If an overcurrent occurs, the circuit breaker immediately shut down the circuit safely.