Tour - Electr(on)ics


A starting delay circuit


by simply decreasing the voltage supplied to the motor (f.i. by inserting diodes) results in the negative effect of a reduced maximum speed. This may be irrelevant with some models, but it definitely looks odd when the V200 crawls along the tracks with some Bm/Am cars at a model speed of almost 60km/h, while 24V are supplied to the track.
A circuit had to be developed which would provide 0-24V to the motors and which would start to provide the motors with voltage only above 6V on the track. Below 6V on the track, the motors had to remain inactive and only the illumination and the sound module had to be supplied with power.
It was somewhat of a challenge to provide the motors with power in the way described above as the motors consume up to 4A. After a couple of experiments it turned out that it was feasable and that it was a better idea the circuit would adapt the voltage between 0 and 19V only. The following diagram shows a circuit which allows for this behaviour:

    The motors remain inactive below 6V, above 19V an adaption is no longer necessary - track voltage is supplied directly to the motors then.


The picture on the right shows the board mounted inside the V200. It's physical size allows for a mounting between both of the walls inside the loco.
The circuit is connected between the DCC interface's pins providing the track voltage and the motors.

The pictures below show the different voltages on the track and at the motors. Two meters are used for a parallel measurement.

The yellow meter shows the motor voltage (1.14V on the left, 14.89V on the right), while the black one shows the track voltage (7V on the left, 15.9V on the right).

V200 start delay circuit



6V on the track but inactive... but in a moment...

above 19V the motors are supplied with the voltage supplied to the track


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