V170 NOHAB

[Steven G.]

Hello,

I really like the Zusi V170 NOHAB-GM locomotives. The Fuehrerstand is excellent and the GM 567 Sounds are really great.

However, I am finding that it is very easy to overload the locomotive when starting a train - (Fahrzeug ueberlastet - max. Strom ueberschritten.) When attempting to start a train the locomotive will go to Notch 3 ok but will overload in Notch 4. It is very difficult to start a heavy train on a gradient. I know it has been mentioned previously in another thread, but I am wondering if the real V170 locomotive operates like this or maybe something could be improved?



I have some experience with operation of similar GM locomotives in Australia. Some observations relating in particular to older GM Diesel Electric locomotives:

Accepted technique for starting/accelerating:
- Throttle initially move up to Notch 3, if train does not start, move to Notch 4, if it doesn't move then to a maximum of Notch 5. (Train should start in Notch 5.) With a very heavy train, the Load Meter (Strom/Ammeter) may go to full scale. (>> 1000A per motor.)
- The locomotive must not be allowed to remain stationary with power applied for any length of time or damage to the Traction Motors may occur due to overheating.
- It is permissible to keep the load meter (Strom/Ammeter) pointer at full scale while the train is accelerating. As the train accelerates, the Load Meter current reading will reduce. As soon as Load Meter pointer starts to reduce, the Throttle should be opened another Notch.
- For the best acceleration the objective is to get Locomotive into Notch 8 as soon as possible using the above technique.
- Once in Notch 8, the Load Meter should continue to show a slow decrease as the train accelerates. If the pointer stays in the overload area, operation can be continued until the time limit for the overload rating expires.

General observations:
- Locomotive may be operated at very low speeds with the throttle in Notch 8 position.
- Locomotive in most cases may be operated up to the limit of the adhesion attainable. (ie The limit of adhesion will most likely be reached before the short term Generator or Traction Motor current limits are reached. The locomotive wheels will slip before any immediate generator/motor damage or overload occurs.)
- Locomotive traction system may have no automatic electrical overload switch. It is up to the operator to observe the Traction Motor current/time limits. If these limits are exceeded, eventually the Traction Motors or Generator may overheat, catch fire, melt etc. (The end result of this overload damage may eventually cause a Ground Relay event which will stop the Generator output and may shut down the engine.)



I'm not sure, but given the common evolution and similarity of the Diesel Engine/Main Generator/Traction Motors/Cab Controls with the V170 and the locomotives that I am familiar with, possibly some of these observations may be relevant to the V170 as well?

Hopefully this is helpful.

Best regards,
Steven.

[Andreas Karg]

At which throttle position does the Load Meter go to full scale when the train is stationary? And at which speed is it usual to run at notch 8? If you tell me this, I can try to tweak the V170 a little...

[Mirko]

Howdie Steven!

Notch 5 is too much for the Zusi-Nohab. 3 and 4 work fine, the rest of Your manual is correct. Please take into consideration, that the NOHAB has a quite small engine. So maybe You're used to have GM engines with bigger trains. I have built a fictive engine based on Your ML1 with two original GM heads but free dimensions as I did not have any scaled drawings. I powered it up from NOHAB's 1435kW/1924hp to the EMD F9's 1980kW/2655hp.
Unfortunately in my ZIP file there is a wrong installation path so I have to rezip before You can download it. As appetizer I link a screenshot.


(Seems like I have to translate my website soon)

Mirko

[Steven G.]

Andi, Mirko,

Thanks for the replies.

I have since tried a few changes to the files to see what I could do. I think it might be an improvement. I would be interested to know what you think.

I have increased the 'max. Strom [A]' parameter in the .lok file to 8500 to avoid the overload cut out situation. It is up to the operator to be careful when driving to avoid overloading/overheating the locomotive.

Since the Load Meter should indicate Traction Motor Current (per Motor not total Generator current), I have changed Instrument_2 to reference 'Zugkraft pro Achse' instead of 'Strom'. In most circumstances the Zugkraft should be roughly proportional to the Traction Motor current. The Load Meter in the Zusi V170 bmp fuehrerstand seems to go from 0 to 1500A, it looks like the numbers are 300, 600, 900, 1200, 1500A? I have tried to recalibrate this instrument to give reasonable current readings using the Zugkraft value. With these changes the locomotive now also shows some reasonably plausible Load Meter readings for most situations including at the minimum continuous speed of about 20km/h. (The locomotive should be able to run in Notch 8 at the minimum continuous speed for any length of time without excessive Traction Motor current and/or overheating.)


Changes to V170_V24.fst:

[----ZEIGERINSTRUMENT----]
Instrument_2%01
6
[Pkt 1]
568
423
15658734
#IF
[Überdeckende]
#
[Überdeckte]
#
0
0
0
3
[Stuetzpunkt]
49,00000
15658734
31
2
0,00000
0
0
#
[Stuetzpunkt]
-1,00000
15658734
31
2
38,00000
0
0
#
[Stuetzpunkt]
-51,00000
15658734
31
2
76,00000
0
0
#
#IF



I have also changed Instrument_3. I think this instrument in real life is the 'Battery Charging Ammeter' with a centre zero indication? I have changed this so that the instrument shows a small deflection to the right of centre when the engine is running (showing the battery is being charged), and the deflection increases slightly at Full Throttle (I have linked this indication to Motordrehzahl). When the engine is shut down (Motordrehzahl=0), then meter will show a deflection to the left (battery is discharging).

Changes to V170_v24.fst:

[----ZEIGERINSTRUMENT----]
Instrument_3%01
9
[Pkt 1]
373
622
15000804
#IF
[Überdeckende]
Melder_1
#
[Überdeckte]
#
0
0
0
3
[Stuetzpunkt]
167,00000
15000804
20
2
0,00000
0
0
#
[Stuetzpunkt]
178,00000
15000804
20
2
275,00000
0
0
#
[Stuetzpunkt]
186,00000
15000804
20
2
835,00000
0
0
#
#IF




Best regards,
Steven.

[Rbnqss]

I like Nohab's too, One of kind was in finland at test drives too in early sixties if i remember correctly. Now wich route ican drive this loco, and is it called V170 or what?

[Steven G.]

Hi,

Zusi routes which currently have the V170 loco:

Route: Netz_Suedniedersachsen / KBS350, Fahrplan: 'Fpl_2000.fpl', Train: 'DFG80210'
Route: KBS850_Lichtenfels-Hof / Stand2001, Fahrplan: 'Frueh.fpl', Train: 'DNG87864'


Steven.

[Rbnqss]

Thanks. Now i got change to test V170, and i have to say that i just love the sound of the engine. It is hard to operate at the start but when ypu get familiar with it's behaviour when accelerating with heavy train, it is oiece of art.