Dcc speed steps If you are using Digitrax decoders with command stations made by other DCC companies, you may need to program CV29 to a value that gives 14 speed step Dec 19, 2014 · Because DCC is a digital system, discrete speed steps define locomotive speeds. 896 = 1. Without known what speed step command is actually being sent to the model you don't really know 100% that the decoder is the problem. DCC has 128 speed steps, but the first two speed steps 0 and 1 are represented by stop and emergency stop. The DCC standard calls for 14 forward and reverse steps for speed control. Determine which loco starts the slowest, or lowest speed step, preferably speed step 1. The decoder, if set to 28/128 in CV29, will handle either situation (as long as it can handle extended packet formats, and I doubt if you could find a relatively current decoder that doesn't). And if that's not enough, how about 128 step operation. In order to operate your loco properly, you may need to change the speed steps setting to match the decoder’s speed steps. Which of these it's using is set in the command station and not in the decoder. Using 28 speed steps: 2 × 0. See if speed matching DCC locomotives with CV2, CV5, and CV6 do it for you. With 128 step operation you have extremely fine Unlike 14 and 28 speed step DCC command, the DCC command to send a 128 speed step command to a given locomotive requires a lot more data to be sent to the locomotive. Run the locos at the top speed and adjust the Faster one to match the Slower by using the Maximum Voltage (aka VMax or CV5 … or CV94 if you are using the speed tables). To select other speed steps settings, press SPD STEP repeatedly until you see your desired speed steps If Bit 1 is set to a value of 1 (its default value), the multifunction decoder will operate in 28/128 speed step mode. With DCC there are two methods for setting speed curves - Default speed curve calculated from CV2, CV5 and CV6 and a user defined speed curve where you can set each speed step in turn using CV's 67-94. the equivalent of 5 on a decoder set to 128 to achieve providing the other CVs relevant to acceleration are set as standard. 128 speed step confusion may have something to do with the way the MS2 visualizes this. You can only take the total speed and divide it up into 28 steps or 126 steps. Let's look first at the top of the pane: You now have the option of using Basic Speed Control (this pane) or Speed Table to control your locomotive's speed. Many factors, including the motor, drivetrain, gear ratios, manufacturing design, and track voltage, determine the maximum available speed. Some locomotives come equipped with DCC decoders already installed on board, while some are Feb 4, 2016 · Similarly, setting a decoder to run on 128 speed steps gives you finer control over your speed because instead of, say, 1/4 volt between speed steps numbering only 28, with the resultant noticeably and immediate change in speed (not very realistic). When you divide 126/28 you get 4. Dec 11, 2011 · He uses 28 step mode AND the "nudge up lots of steps" button for speed control, so effectively has about 7 speed steps. With this table the values are specified for 28 speed steps. e. I want to consists the two sets to run back-to-back giving me a nice A-B-B-A consist. , “speed steps”) to motor speed. Aug 3, 2024 · Summary: Speed steps are the divisions between Stop and Maximum Speed. Decoders can also have 14/27 speed steps, but this is set in the decoder in CV 29. 5. Send us your questions Figure 3—Speed steps The more speed steps, the finer the control over the motor’s speed. In the 28 speed step mode there is one value for each speed step. Some command control systems (previous to NMRA DCC) advertised forward and reverse speed steps combined - 128 speed steps would be 64 forward and 64 backward. At this rate, the vehicle will take 1. Multifunction decoders can use 28 or 128 distinct values, older decoders may only accept 14 values. 0 uses CV s 2, 5, 6 to determine speed, 16 uses speed table values found in CVs 67 to 94. You may have heard about 14, 28, and 128 speed steps, but what does that mean and why does it matter to you? G Feb 10, 2010 · The difference between 28 and 128 speed steps is whether the controller sends a normal speed command or an advanced operations speed command. the DZ120 from Digitrax support the table however only in the 28 speed step mode. the throttle speed step indicated. been stored in the Cab’s memory), Prodigy Advance will set 28 speed steps as the default setting for that address. Read the Speed Steps article for more information. But with DCC, when you're using the 128-speed step mode, there are 126 speed steps forward and 126 speed steps in reverse [13] . 792 ÷ 28 = 0. I gave one set an address of 17 the other 117. The speed step CVs 67-94 are designated in 28 steps (ie CV67=speed step1, CV68=speed step2 etc). com Oct 19, 2010 · For best performance, when using Digitrax decoders on Digitrax systems, set CV29 to a value that gives 28/128 step speed control and make sure the system is set to run in 128 speed step mode. 064 Seconds per step. Bit 2 (value 0 or 2) controls number of speed steps. But, all his locos have their speed curves optimised for running on this layout, so top speed is the top speed on the layout, etc. Sep 9, 2024 · I'm trying to understand the speed step CVs and understand how they correlate to 128 speed steps. A DCC decoder is "commanded" to a particular speed by receiving an instruction, but there are different "speed steps" that are the increments or granularity of speed attainable between your start speed (CV2) and your top speed (CV 5). If a multifunction decoder is configured for 14 speed steps, and operated using 28/128 speed steps, the headlight will toggle on or off with each throttle increment or decrement. Custom Speed Tables are what you need to program, not speed steps. Through decoder settings, we can adjust the startup voltage to get it to start moving at speed step 1. See full list on dccwiki. In the 128 speed step mode the decoders produce additional values by interpolation. My problem is that one set (#17) has 14 speed steps and the other has 128. Nov 29, 2017 · I wasn't forgetting that you are new to DCC control but was pointing out that for every increase of 1 speed step in a decoder set to 28 speed steps it would take approx. 896 × 100 ÷ 128) × 128. This can be adjusted to a user’s preference, but adjustments will vary depending on the manufacturer of the decoder (and on the decoder model, in some cases). KB929 Speed Steps Explained - 14, 28, 128. Dec 18, 2014 · Speed Match them at the Fastest Speed Step. com | August 2013 47 ore often these days we see the letters “DCC” pop up in large scale. In this video, George talks about speed steps. . So in 128 steps, does CV67 impact steps 1,2,3,4? Does speed Apr 19, 2014 · A side note: The 126 vs. If you are using older command stations or decoders you may need to adjust one or the other to get the trains to run. Sep 7, 2012 · The earliest digital controllers used 14 speed steps - within the capability of the processors in use at the time: Zero-1 14 steps, Motorola-80 etc and early 'Lenz' (that was to become nmra dcc) also 14 speed steps, which is why LGB still uses 14 speed steps in MTS . What you need to do is determine the manufacturer and type of decoder that is in each locomotive, and then . If you want to know more about speed matching DCC locomotives, check out Larry Puckett’s DCC Corner column “Speed matching for DCC consists” in our September 2016 issue. 0 for 14 speed steps, 2 for 28/128 speed steps Bit 4 (value 0 or 16) controls whether a speed table is used. You can choose between either control method using the 28/128 button on the bottom row of your keypad. 8 seconds to reach its top speed (128 steps, or 100%). Jul 27, 2015 · There seems to be a little confusion on DCC speed steps. g. Most modern command stations and decoders are set up to run 28/128 speed steps. Originally, a long time ago, there were 14 speed steps. Jun 4, 2024 · The acceleration rate is 14mS per step. Why are more speed steps better?The reason you want to use a command station and decoders with 128 speed steps is for smoother speed control of your I own a Pricom DCC tester (it is basically a very powerful DCC packet sniffer) and it can be very revealing as to what speed step is being sent to the decoder vs. Thus reducing the actual number of speed steps, where the locomotive can be expected to move, to 126. Speed Tables In a DCC decoder, a speed table controls how the decoder maps throttle settings received via DCC (i. extern void notifyDccSpeed (uint16_t Addr, DCC_ADDR_TYPE AddrType, uint8_t Speed, DCC_DIRECTION Dir, DCC_SPEED_STEPS SpeedSteps) __attribute__ ( (weak)); * notifyDccSpeedRaw() Callback for a multifunction decoder speed command. I understand the 128 speed step method includes "stop" and "e-stop", leaving you with 126 speed steps. The command station receives a throttle input, computes a value based on the number of speed steps, and transmits that value to the track. Older decoders e. 1 14 speed steps DCC 28 or 128 speed steps DCC 0 2 2 Disable analog operation Enable analog operation 0 4 3 Disable RailCom® Enable RailCom® 0 8 4 Speed curve through CV 2, 6, 5 Speed curve through CV 67 - 94 0 16 5 Short addresses (CV 1) in DCC mode Long addresses (CV 17 + 18) in DCC mode 0 32 CV Name Description Range Default For what is it worth, I believe that PCM was a branch of BLI at one time. 792; 1. Sep 17, 2004 · Whether or not you can program 128 Speed Steps depends on the type of decoder that is in your locomotives – some older decoder can only be set for 14 or 28 Speed Steps. 14 Speed Steps 28 Speed Steps 128 Speed Steps www. In this step, we are only interested in what it takes to get the loco moving from a dead stop. Increasing the value in CV3 to 100 will result in the vehicle reaching its top speed in 90 seconds (0. Depending upon your DCC system this will probably be either SS 100 or SS 128. Sep 26, 2020 · The default setting for most decoders is 28/128 speed steps. This sounds terrible, but works incredibly well on _his_ layout. Use the tabs at the top of the screen to select the method you wish to use and then click the button in the top center for the page to select that method of speed control. for my El Capitan. Some decoders offer advanced 28-step operation to give you even more speed control. Simplistically, It takes twice a long for the DCC command station to talk to a 128 speed locomotive on the track as it does talking to 14 or 28 speed step locomotive. however their decoders for many years have also accepted the later nmra standards of addressing including 28 / 128 speed Aug 7, 2022 · But as I said earlier, this is likely not necessary. GardenRailways. adnvhh vdavto ntqhfwqb emdoif utxq ohuh cmh dpab xtzsd wmiblty ktqnu kbyprdx qqsl ralda ahcx