The effect of the dynamic brake in TSW 2 seems to decrease with speed, i.e. the faster you are going the less effective the dynamic brake becomes, Is this accurate? I would suppose that the faster the traction motors are turning under dynamic braking the more energy they will produce thus more braking effect. Once the speed drops below a certain point of course no energy is generated and dynamic braking becomes ineffective.
It should be accurate although I don't know technical details. Faster speeds means less effective dynamics.
Yes that's accurate. Remember the higher your speed the more energy your consist has - dynamics only apply on the locomotives. So they're most effective at around 20 - 30 mph.
On the Sherman Hill streams, Matt gave 30 mph as the point of diminishing returns for dynamics. Don't know whether that's a universal thing across all routes and locos, but I've been going by that when doing U.S. freight runs, and it's worked well.
The dynamic brakes are broken on this train and have been for a long time. Above about 28 mph the braking force should drop off but before that, the braking force should be fairly linear and increase with more input on the brake lever. The bug… It is as mainly you describe for the whole speed range (not just above 30) and the braking force is incredibly high when you are hardly moving and drops off proportionally with speed, which is not correct behaviour. Notches 5 to 8 have no effect either. (The dynamic brake isn’t actually notched but it is an easy way of describing how much brake is added). There are many threads on the forum from over the years describing the bug but just as many people who deny that there is a bug at all. There definitely is and DTG have not fixed it although it did appear as scheduled for a fix on the roadmap for a while. The Sherman Hill dynamic brake is much better but still not fully correct as it still has the unrealistic massive braking force at very low speeds.