The most common example is the three-position controller. 最通用的例子是三位置控制器。
The vacuum circuit breaker and three-position disconnector are designed for C-GIS and special micro-computer controller for the three-position disconnector is developed. 介绍了C-GIS用真空断路器及三工位隔离开关的设计技术;运用微机技术开发了专用的三工位隔离开关控制器;