Freno Gradual

Dependiendo del vehículo motorizado, hay dos formas de controlar la presión de la tubería del freno: con control gradual y la más antigua, mediante aplicación y afloje manual.

En los sistemas con control gradual, la presión de la tubería del freno se maneja automáticamente. El maquinista puede colocar la palanca del freno automático en cualquier posición dentro de un rango. Cuanto más se ajuste en la dirección de "aplicación", mayor será la fuerza de frenado y viceversa. La válvula maneja automáticamente el vaciado o la presurización de la tubería del freno dependiendo de la posición de la palanca.

On non-self-lapping systems, the process is more hands-on. The lever has a few fixed positions. Two of the positions, called “release” and “service” can be thought of as adding and releasing the brake pipe pressure, respectively. The position in between them, called “lap”, is used to maintain whatever pressure is in the brake pipe. The furthest position, called “emergency”, will release pressure at the fastest possible rate.

Auxiliary reservoirs are being drained when braking. When the brakes are released, it takes some time for auxiliary reservoirs to fill up again. The lap position, however, functions only if the auxiliary reservoirs are full. To stay in full control over braking it is recommended to not release non-self-lapping brakes when knowing that moments later braking may be needed again. Calculated, slow moves are preferable when releasing the non-self-lapping brakes.

With both brake types, the driver can see exactly how much braking force they are applying by looking at the brake pipe and brake cylinder gauge needles.

Ambos sistemas son bastante simples de usar, aunque el gradual puede ser más intuitivo para los principiantes. En términos simples, con control gradual, el dispositivo de control establece la fuerza de frenado deseada, dejando que la válvula automática haga el trabajo, mientras que en el manual, el dispositivo de control establece directamente la fuerza de frenado.

In case a train contains motorized vehicles with both self-lapping and non-self-lapping brake valve types, only the self-lapping ones will be functional when operating the brake. For that purpose, vehicles are also equipped with brake cutout valves, which can be used to isolate certain vehicles from the brake system and resolve this conflict.