ProtoThrottle Progress

Setting up ProtoThrottle

Over the weekend, I set up the decoders in my GE 44 Tonner and my Gas Electric to work with the ProtoThrottle, and I’m very pleased with the results.

Introducing the ProtoThrottle to a layout is a multi-step process.

– The ProtoThrottle must be connected to the layout’s DCC system (which I wrote about earlier this month).

– Each locomotive that will be used with the ProtoThrottle must have its decoder setting tweaked. This isn’t necessary to run with the ProtoThrottle – but doing so allows one to leverage all the capabilities of this realistic control stand.

– For each locomotive, a configuration must be built and saved within the ProtoThrottle itself. This includes address, plus settings such as the braking behaviour, notch points for the throttle, and rules governing the lighting switches.

For this work, it definitely helps to have a programmer at the workbench. Depending on the decoder being used, that’s going to be either something like DecoderPro (JMRI) or – in my case – the ESU LokProgrammer. (These are good ideas for anybody with even a single sound-equipped DCC locomotive, regardless of whether one’s using a ProtoThrottle, because they greatly simplify setting CVs.)

To provide an idea of what’s involved, I’ll share the adjustments I made for my 44 Tonner. I’ll also share some of the adjustments I made for the gas electric, to demonstrate some of the changes one might consider for a locomotive with different performance characteristics.

ProtoThrottle set up for CNR #1

Proto Throttle - Port Rowan

The ProtoThrottle can store up to 20 configurations. These include the locomotive address, function mappings, throttle notch settings, and other options. These are some of the values that went into the configuration for my 44 Tonner, which is equipped with an ESU decoder and a sound file with the Full Throttle features:

Under the Configuration Function menu (CONFIG FUNC), I set the Horn to F02, Bell to F01, Brake to F10, Brake Off to F — (not set), Aux to F09 (to enable Drive Hold) Front (F) Light to F00, F DIM #1 to F00, F DIM #2 to F12, Rear (R) Light to F05, R DIM #1 to F05, R DIM to F12.

The next task was to match the engine sounds from the decoder to the notches on the ProtoThrottle. When I move from Notch 3 to Notch 4 on the throttle, I want to hear the model notch up accordingly. To determine the notches for my 44 Tonner, I first ran the locomotive with a regular DCC throttle equipped with a speed step indicator. Working with 128 speed steps, I increased the throttle one speed step at a time, and made a note of the speed step at which the engine sound changed – in other words, the point at which the decoder generated a “notch up” sound. I then picked values that lay between the notching steps.

For example, if the decoder notched up from 2 to 3 at speed step 20, and notched up from 3 to 4 at speed step 35, I decided that notch 3 would be set to speed step 29.

Having noted the values, I then returned to the ProtoThrottle. Under the Notch Configuration menu (NOTCH CFG), one sets the speed step that each notch on the ProtoThrottle will send to the decoder. As noted earlier, this can be set for each of the 20 configurations saved in the throttle. Based on my tests, I set the notches for CNR #1 as follows:

1 = 8, 2 = 17, 3 = 29, 4 = 40, 5 = 49, 6 = 60, 7 = 70, 8 = 90

Finally, I configured the brake handle. I tried both approaches, and decided that I did not gain anything by using the Variable Brake capability. So in the OPTIONS menu, so I set this to OFF. I also set the emergency stop to OFF, since I’ve never needed it using other throttles on my layout.

That completed the configuration of the ProtoThrottle for CNR #1. I saved the configuration, then turned to the decoder itself.

Using my LokProgrammer, setting the characteristics for the decoder in CNR #1 was intuitive and adjustments were easy. It required a fair bit of time, however, as I would make a change or two, then switch to driving mode and test my updates.

I wanted to use a Full Throttle file from ESU, but while ESU offers a sound package for a 44 Tonner, it has not yet been upgraded to include Full Throttle features. The great thing about Loksound decoders, though, is that I can load anything into the decoder for now – and upgrade it to the proper sound file if/when it’s made available. 44 Tonners were powered by a pair of Caterpillar D17000 V8 prime movers. I scrolled through the Full Throttle options and decided that the file for CP Rail’s oddball CAT 3608-powered M636 would do for the time being. (Again – I know that’s not right. But I can update the sound if/when the correct file is available with Full Throttle features.)

I won’t list every value here – that would take a book – but I will share the thinking behind some of the key decisions I made. (I’ll include the LokProgrammer language for those who use it, but also try to explain it so it doesn’t sound like gibberish to those who do not.)

Under Motor Settings, I enabled Back EMF and the heavy load/coast load settings that enable Drive Hold on a Full Throttle-equipped Loksound decoder.

Still under Motor Settings, I then used the Three Values option (Voltage Start, Voltage Mid, Voltage High) to adjust the motor speed. In the LokProgrammer, there’s a graph for this, with a slider. I dropped the top speed (V High) from 255 to 50. That may seem slow, but I get frustrated when I’m running on a layout with a throttle that offers me 128 speed steps, and I’m stuck using about 25 percent of that because anything higher is too fast. What’s the point of having 128 steps if you’re never running above speed step 30? So on my own layout, I knock down the top speed of every locomotive so that I can take advantage of the full range of speed steps on the throttle. According to this neat article about the prototype, GE 44 Tonners were limited to a top speed of 45 mph, “although it’s doubtful many actually achieved it”. What’s more, the top speed on my layout is a blistering 20 mph. Scale speed is subjective – what works for me may not work for others – but to my mind, setting the maximum voltage to 50 seemed to provide the right top speed for this little locomotive.

Under Driving Characteristics, I set Acceleration Time to 170 (42.5 seconds from full stop to top speed) and the Deceleration Time to 255 (63.75 seconds from full speed to stop). High values for these settings serve two functions. First, they allow the prime mover sound on the decoder to ramp up before the locomotive moves… or drop off to idle while the locomotive continues to roll (representing the momentum of a heavy object rolling on rails). Secondly, on the ProtoThrottle they smooth the transition from one speed step to the next.

Obviously, one can get into real trouble with the deceleration set at 255. On my layout, the 44 Tonner running at full speed (which is not very fast) will roll about 11 feet before coming to a stop if I simply drop the throttle to “idle”! That’s where the brake handle comes in. Under Brake Settings, I set the Dynamic Brake to 64. This will bring the locomotive to a stop from its maximum speed in 16 seconds. I arrived at this value by testing the locomotive to find a brake that was responsive enough to allow me to stop the locomotive where I wanted to fairly reliably, without being too aggressive. With the Dynamic Brake set to 64, CNR #1 will go from full speed to full stop in about 15 inches when the throttle is shut off and the brake is applied.

The following Function Mapping are relevant to the configuration settings in the ProtoThrottle. To set up the front and rear lights so they work with the throttle’s rotary switches, I mapped the physical outputs for the front light to FO(Forward) and FO(Reverse), and the rear light to F5. To enable dimming, I mapped the logical function on F12 to “Dimmer”. (For each light, I also entered the Function Outputs menu and set them up as dimmable lights with fade in/out, knocked down the brightness a bit, and enabled the Dimmer and LED mode special functions.)

Again, these are all personal preferences, based on setting values, then running the locomotive and making notes of what worked and what didn’t. If you have a ProtoThrottle, don’t simply do what I did: do your own tests and pick settings that are right for you.

Proto Throttle - first run with Gas Electric

I also set up my gas electric. Many of the settings are the same as in the 44 Tonner – in both the model’s Loksound decoder and the ProtoThrottle configuration. For example, the front headlight settings are the same. Since the model does not have a rear headlight, I disabled those settings in both the decoder and on the ProtoThrottle.

As a passenger unit, I wanted the gas electric to have a higher top speed than the 44 Tonner. Therefore, using the slider under Motor Settings, I gave it a top speed of 100 (versus 50 for the 44 Tonner). Note that this does not mean the gas electric goes twice as fast as the 44 Tonner: each model has a different drive train set-up, including unique gear ratios. So I set the top speed based on each model, by setting a value, testing the unit on the layout, and adjusting as necessary.

I also wanted it to have snappier throttle response so under Driving Characteristics, I set the Acceleration Time to 125 (versus 170 for the 44 Tonner) while keeping the deceleration value at 255.

The introduction of the ProtoThrottle has definitely been worth the investment for these two models. Switching with the 44 Tonner is a completely different experience than it was with a standard DCC throttle. And driving the gas electric with the ProtoThrottle makes a straightforward passenger run into a much more engaging experience. I’m glad I did this, and I look forward to setting up more locomotives to take advantage of this throttle. As mentioned in a previous post, I need to upgrade the decoder in my CNR RS18 and the ProtoThrottle is the incentive to move that project up the to-do list.

Now, when will I see a “Proto Johnson Bar” controller for my steam engines?

8 thoughts on “ProtoThrottle Progress

  1. A video of them in action would be awesome!!!! 🙂 Can’t wait to get one once my new setup is complete. Thank you for sharing this great info!

    • I may do a video, in time. But those looking for videos of this throttle should join the ProtoThrottle Group at IO. A number of throttle owners have posted videos showing it in action on their layouts, and they’re all posting the links to this group.
      Cheers!

  2. Great post! Look forward to hearing more about your experiences with the throttle. Looks like I’ll have to seriously consider the throttle on my own layout.

  3. “Now, when will I see a “Proto Johnson Bar” controller for my steam engines?”

    Wasn’t that the thinking that led to Scott creating the Proto Throttle in the first place?

    Over to you, Trevor… 😉

    • Yes, I suppose it was. But I already have enough irons in the fire. I’ll gladly buy them from someone else – more than one, even! – if it’s the same quality as the ProtoThrottle.
      Cheers!

      • So would I.
        Sorry: I couldn’t resist the chance to be a smart-donkey… 😉

        But I suspect that how it would work would be different: when coasting, a steam engine needs to have the volume of the chuff reduced to all but zero, but when working hard, the volume and the attack of the sound wave need increasing substantially, then to gradually trail off. The better sound files probably do this already, but what would be great would be the ability to notch-up the valve gear separately from the regulator do that you really have to drive the loco, and I am not sure if that’s possible with existing sound files.

  4. This makes me very jealous as it takes prototypical operation to a whole new level. I’m confused as to what heavy load/coast load does for using ESU Full Throttle as I have decoders equipped with FT but haven’t enabled heavy load/coast load. Do they help to make the operation even smoother for FT even without using a Proto Throttle? Also did you use a full speed table for both engines and then used Vmin and Vmax to little the to end ranges of your speed table?

    • Hi Blane:
      Possibly, heavy load and coast load relate to steam settings and they’re not used for the diesel. To be honest, I don’t know. They were checked. I left them checked.
      I did not use a full speed table. I used the default three-point (start, mid, high) settings. I then grabbed the slider on the right side of the graph and pulled it down to the maximum speed. The program set the intermediate setting automatically.
      Don’t be jealous. The ProtoThrottle people are making more. And while it costs more than one but less than two HO sound equipped diesels, you will find that you don’t feel the need to buy anymore diesels after having one of these.
      Cheers!

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