"E" Series Interval
- When wiper switch is placed in Interval mode, wiper motor park switch contacts are grounded and governor relay is energized. Initially current flows from ignition switch through circuit breaker in wiper switch, through a diode and energized contacts in governor, to wiper motor low speed brush. See Figure .
- The motor rotates 1/10th of a cycle. Park switch contacts move from Park-to-Run position. After contacts change position, relay in governor de-energizes. Wiper motor rotates through remaining 9/10th of one cycle. When park switch contacts touch ground again, motor parks. Governor electronic circuit delays energizing relay until circuit times out.
- Then relay energizes and low speed interval is repeated. The discharge rate of a capacitor to ground through wiper switch variable resistor controls time delay of system.