| 摘要 |
A pulse encoder digitally derives a first value of speed at which the cage is moving at any given time. An analog device, such as a tachogenerator, derives the second value of the speed, in analog form, at which the cage is moving at the same time. The two speeds are compared in a comparator to determine the differences therebetween. If the difference exceeds a predetermined limit, an emergency stop is tripped to arrest the motion of the cage. |
