| 摘要 |
<p>The control system uses two identical control units either one of which is in use at one time, with the other unit switched into operation if the first unit fails. The selection of either unit is made in dependence on the direction in which the vehicle is to travel, e.g. using a travel direction selection switch (6) between the control units (1,2) and the controlled device (7), determining which of the output signals (4,5) is fed to the latter. Both units (1,2) are tested by alternately activating them for selected operating times using the selection switch (6), so that a failure of the stand-by system can be detected. The coupling between the selection switch (6) and the direction selector (8) can be interrupted when one unit (1,2) is faulty to allow the other to be coupled to the controlled device independent of the direction of travel.</p> |
