| Electronic control unit | |
| Automatic temperature control system | |
| A signal that varies the ratio of on-time to off-time, resulting in a square wave that can range between zero and 100; in a process, the ratio of on-time to total cycle time; in fuel injectors, the percentage on-time to total cycle time; in solenoids, the percentage of on-time to total cycle time. | |
| A rotating shaft that rotates another part, such as it wheel. |