Dynamic Brake Question

Hi guys,

While I was doing the Cumberland charge scenario I was applying the dynamic brakes in the downhill (notch 8) and for some reason, they stopped working, no AMP reading in the gauge, the cooling fans turned off, and the train started accelerating. I don't know if it was a bug in the game or it has to do with something I did wrong. The dynamic brakes were in notch 8 for a long time, maybe does that has something to do? is there a technical limitation on the time the dynamic brakes should be used?

 

Perhaps you didn't have air left in the tanks.

Here is a turorial. The first answer is a list of the subjects.

 

Hey, thanks for your reply and for sharing the video, I will have a look. But still I don't see how not having air in the tanks could affect the dynamic brake, as far as I know they don't work with air

 

That shouldn't have happened. IIRC, in the Cumberland Charge scenario you're driving a GP38-2, right? Dynamics should work all the way down; those locos have truly massive heat exchangers.

 

Dynamic brake has no interaction with the air brakes. There shouldn't be a time limit on dynamic brakes either. I am wondering if there is an interaction where if you start to wheel slip with dynamics on, that the train cuts them out automatically.

 

The only thing I can think of is that the OP for some reason engaged the independent brake.

 

Yes it is a GP38-2. Then probably was a bug in the game, I will see if I can reproduce it.

 

Interesting, but I did not notice any wheel slip nor any alert in the control stand.

 

I'm not sure what is OP

 

Sorry: Original Poster. I.e. you.

 

Even if you have massive heat exchangers, you can still overamp it. Creating more current flow than the wiring in the motors is designed for. This will trigger an overamp protection. Dunno if this is also modeled for dynamic braking, but is definitely modeled for power, and exceeding the amp limit will result in excatly what OP experienced - loco basically shutting down.

@gilbertojrequena
Do you remember how high the amps were when it happened?

 

Yes, in theory that is possible: but the traction in that scenario is well capable of handling that smallish consist on that grade without either triggering.

 

I did not interact with the independent brake, I applied the automatic one some times while the dynamic was engaged

 

I think that could be what happened, I don't remember exactly how high the amps were. I remember I saw the power gauge a couple of times, and the needle was close to the red area. But the loco did not shut down, just the dynamic brakes stopped working.