Inviato: giovedì 19 novembre 2020, 21:09
Come è possibile impostare la max velocita' su un decoder esu a parte la CV 5 e 6 ? Il valore max che mi lascia programmare è 64 con una marcia assai lenta
Dedicato alla diffusione della cultura fermodellistica digitale.
Parameters of Back EMF control
The internally used PI-control algorithm of Back EMF control depends on 3 parameters: the control reference voltage is stored in CV 53, the control parameters are in CVs 54 and 55.
In CV 53 you set the voltage that should come back from the motor.
This value depends on the track voltage and the coefficient of utilization of the motor. A coefficient of 75 % and a track voltage of 16 Volts adds up to a voltage of 16 V * 75 % = 12 Volts. This value has to be written into CV 56. The voltage (here: 12 V) may be entered in 0.25V-increments. This results in a value of 30 (12 V * 2.5) for CV 53. If you don’t know the exact motor coefficient, you may obtain the
value experimentally as follows:
Check if the engine really reaches top speed at the highest speed step or if you cannot detect any speed changes at the maximum speed step. In the latter case you have to reduce the value for CV 53, in the first case increase the value.
The internal PI regulation of LokSound can be adjusted with CV 54 and CV 55.
Depending on the type of motor the parameters may have to be adjusted to achieve optimal running performance.
LokSound decoders are factory pre-set for the use with ROCO®-, Brawa®- or Kato motors.
Parameter „K“, stored in CV 54, influences how strongly load control will effect the driving performance. The higher the value, the more load control will respond to any changes. Adjust this value with care, because too high values could lead to irregular and „hard“ driving performance. If you prefer smooth running, try to reduce the value step by step until you reach an optimum.
Parameter „I“, stored in CV 55 provides important information to the LokSound decoder regarding the motor type used: certain electric motors respond differently to adjustments of the rpm’s. The longer a motor takes to respond, the lower the value in CV 55. However, it is not easy to recognize the degree of inertia. In general: the more poles a motor has and the bigger it is, the more fly wheels it has, the slower it is and the lower the value should be set in CV 55.
For optimal programming proceed as follows:
Read out the value in CV 53 as described above. Leave the value of CV 55 (parameter I .I.) for the time being and test the engine. Now change the value of CV 54 in steps of 5 downwards or upwards and monitor the running properties of the engine. If there is no improvement leave the value of CV 54 and change the value of CV 55 (intensity of control) in steps of 5 until an optimum is reached.