50 cycle vs 60 cycle
50 cycle should not be much of a problem. Expat's from the US use appliances on both sides of the pond all of the time with only a voltage transformer.
Using an appliance designed for 60 cycle on 50 cycle MAY shorten the useful life, and will probably decrease the effeciency.
Assuming your fridge is an ammonia adsorption unit, the main power draw is the resistive heating element, therefore the 50 cycle issue should not be much of a problem.
The AC and the fridge should, however, be put on separate circuits.
The polarity light is a safety feature, designed to indicate (and insure) the "positive" leg of a 110-120 volt circuit is (and stays) isolated from "ground". If unsure of the wiring procedure of the conversion, I would suggest assistance from a professional electrician.
The above information is free, and ultimate accountability is solely the responsibility of the user.
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