Hi - please help me with this problem.

I have installed a Loksound v4.0 54400 DCC in a Marklin loc BR 85 and it run perfect on the layout but when it stop, it jump in the running direction. Not always but most of the time. I can also hear the brake sound after it have stopped.
Did someone know what I have to do? Is something I have to turn off or change?

The loc run perfect with an another decoder. Controller is CS3 and the values in this are put to zero. I have tested CV 51 - 56 up and down with no result. I have read the instructions many times but not got any solutions I can find.

I have converted 6 other loc with Loksound, no problem, the only different for this loc is it have a Cube speaker from ESU.

Torstein.

Do you have a lok programmer or know someone who does? If so, try updating the firmware on the decoder to the latest. Also, based on the Marklin motor type, have you set all of the motor parameters correctly?

For others not as up to speed on the details, the CVs 51-55 control the ESU decoders driving characteristics and are described, for example, in the ESU LokSound v 4 manual on pages 47, 48, 49.

Relative to slow driving behavior ESU states "Especially for the slow driving sector (speed step 1) the LokSound V4.0 with CV 51 and CV 52 to change the gain control. This helps to avoid any jerking while driving extremely slowly. However, before doing this you must make sure that there are no capacitors wired between the motor terminals and the chassis."

In the descriptions of the CV's they state:

CV 2,5,6: (pg 40) when using a 3-point speed curve -
Motor characteristic via CV 2, 5, and 6 (Fig. 25): Enter the start voltage in CV 2 and the maximum speed in CV 5. CV 6 corresponds with the speed at a medium speed step.
So its CV2 (min), CV 5 (max), CV6 (med)

(Starting at page 47)
CV 54:
Parameter „K“, stored in CV 54, influences how strongly load control will affect the driving performance. The higher the value, the more load control will respond to any changes and try to adjust the revs of the motor.
Parameter „K“ needs adjustment if the locomotive runs unevenly (jerks).
Reduce the value of CV 54 by 5 and test-run the locomotive to see if there are any improvements. Reat these steps until the locomotive runs smoothly at speed step 1.

CV 55:
Parameter „I“, stored in CV 55, provides important information to the decoder on how much inertia the motor has. Motors with large flywheels naturally have more inertia than smaller ones or coreless motors.
Adjust parameter „I“ if the locomotive jerks somewhat just before it stops or „jumps“ at lower speeds (lower third of the speed step range) or simply does not run smoothly.
Increase the value by 5 starting with the default value for motors with very small or no flywheels.
Reduce the value by 5 starting with the default value for motors with large flywheels.
Test again and repeat this procedure until you arrive at the desired result.


CV 53:
In CV 53, you set the EMF reference voltage generated by the motor at maximum revs. This parameter may have to be adapted subject to the track voltage and the efficiency of the motor.
If the locomotive reaches maximum speed when the throttle is set to about three-quarter and the top third of the throttle has no influence on the speed, then you should reduce the value of CV 53. Reduce the value by 5 – 8 and test the locomotive again. Repeat this process until the locomotive just reaches its maximum speed when the throttle is fully open.
On the other hand, if the locomotive moves too slowly at full throttle then you should increase the value of CV 53 step by step until the maximum speed is reached.

CV 52:
Together with the LokSound V4.0 decoder an additional CV 52 has been introduced which seperately determines the gain control considerably for the whole slow driving sector in speed step 1.
If you are not satisfied with the driving behaviour when the locomotive drives slowly or starts, while everthing is fine with the medium and high speed steps, you should increase the value of CV 52 by ca. 5 - 10 than the value set in CV 54.

CV 51:
Here you can adjust the inertia of the motor separately for slow speeds and starting from a stop. The desired value is to be entered into CV 51. The parameters “K slow” and “I slow” jointly influence the behaviour at speed steps 1 and 2 while the parameters CV 54 (“K) and CV 55 (“I”) are responsible for the remaining speed steps. The decoder computes a speed curve in order to avoid any abrupt changes.