When I received this machine it was not fully operational.
After cleaning and lubrication it runs smoothly and calculates perfectly.
Apparently grounding wasn’t usual at the time the machine was developed. At the same time this particular machine appeared to be electrically unsafe. Inside the motor there is a ca. 75kOhm connection with the motor housing. Touching a metal part won’t be fatal, but will feel very unpleasant.
With this particular machine I will always use a separation transformer.
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