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Friday 18 May 2018 at 14:51
It will have zero impact. Pinballs reset due to low voltage not frequency. Games can run on the 50HZ from overseas if you want. Score motors in EMs will run at a different speed but modern pinball machines using DC motors do not care about frequency.
Source: http://pinside.com/pinball/forum/topic/us-power-grid-change-60-hertz-immediate-correction-eliminated#post-4404551