According to the manual, Ctrl-R toggles it on and off, and R and F increase and decrease it, just like a normal German loco. But instead, those keys adjust traction force. In fact, the whole keymap for this engine is just bizarre- the HUD suggests it has dynamic braking, but those keys instead adjust brake force. Does the 155 in fact have AFD, or is the manual simply wrong?
First, it is called AFB (Automatische Fahr- und Bremssteuerung). The BR 155 doesnt have this automatic system. This system is implemented on the BR 146, BR 185, BR 182, BR 143. The controls are adjusting the force the traction engines apply at applying throttle. The manual is in fact wrong.
It does have an electric brake, it just works different from what you‘re probably used to. The corresponding lever is like a balancing tool, at 0% the loco will brake using the air brakes only. At 100% the loco will use the full force of the electric brake. The application of the electric brake happens via the driver‘s brake handle. At 50%, for example, the loco will brake using the electric brake at 50% of it‘s full use (no air brakes once the electric brake is ready for use). TLDR: The electric brake handle basically works in the same way as the traction force lever, but for the electric brake. The electric brake is used automatically when using the driver‘s brake handle. Edit: for clarity - electric brake = dynamic brake in German
Interesting. And exactly backwards from what I'm used to, running heavy diesels over Sand Patch. There on a down grade you use dynamic to maintain, pneumatic to stop (or in case max dynamic still won't hold speed). For that matter, even West German/post-Unification locos in effect apply dynamics first (via AFB), then air
I know. I run a lot of SPG as well On a more serious note though, I found a better example to explain it. Maybe you have run the F40PH or the MP36 on SFJ? Their blended brakes are pretty much the same system as the Br 155 uses. The air brakes are applied to reach a certain deacceleration. In that time, the electric brakes are being "booted up" for lack of better term. Once they're ready, they match the brake force which the driver's brake handle is indicating (as much as the electric brake force selection lever is allowing). If the electric brakes are not strong enough to match the selected deacceleration (slow speeds for example), the air brakes come into play again and are applied as well. On this matter That's only because you're used to the modern three-phase AC locos. They can switch between traction and dynamic braking in a heartbeat. Older DC locos need time to switch to dynamic braking (think of the DC locos on SPG). To make sure that brakes apply immediately when using the brake handle, air is applied first while the dynamic brakes are preparing. Sorry for the wall of text. You probably already understand most of that after my initial post, but I thought this explanation is a lot clearer than my previous one and therefore posted it anyway
