Wiring of zinc oxide arrester with series gap four-star connection

2) The wiring operation practice of zinc oxide lightning arrester with series gap four-star connection method
    shows that the protection in Figure 20-43 (a) is not ideal. In order to more effectively protect the high-voltage motor from
the hazards of operating overvoltage, it can be used Zinc oxide arrester protection with four-star connection in series gap. Its wiring is
shown in the figure. It can well protect the insulation between the relative phases and the relative ground of the motor.
 

Wiring of zinc oxide arrester with series gap four-star connection